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Simulium (Simulium) tani Takaoka & Davies, 1995 (complex) Simulium (Simulium) tani (complex): Morphoform ���a���: Takaoka et al., 2015a: 85 ���86. Specimens examined. Seven females and 15 males (all reared from pupae), collected from a river (width 8���10 m, depth 10���15 cm, bottom of pebbles, water temperature 17˚C, exposed to the sun, elevation 162 m, 18˚58���45.918���N/109˚50���10.693���E), fast flowing in a natural forest, Pu Mat, Nghe An Province, northern Vietnam, 9-XII-2015, H. Takaoka, M. Sofian-Azirun, C.D. Chen, & K.W. Lau; four females and four males (all reared from pupae), collected from a stream (width 1.0��� 1.5 m, depth 10���15 cm, bottom of pebbles, water temperature 17˚C, partially shaded, elevation 162 m, 18˚58���45.918���N/109˚50���10.693���E), moderate to fast flowing near a natural forest, Pu Mat, Nghe An Province, northern Vietnam, 9-XII-2015, H. Takaoka, M. Sofian-Azirun, C.D. Chen, & W. K. Lau; 13 females and 14 males (all reared from pupae), collected from a stream (width 1.5���3.0 m, depth 10��� 15 cm, bottom of sands and pebbles, water temperature 18˚C, exposed to the sun, elevation 73 m, 19˚30���45.487���N/ 105˚09���29.261���E), moderately flowing near a natural forest, Chau Dinh, Quy Chau, Nghe An Province, northern Vietnam, 9-XII-2015, H. Takaoka, M. Sofian-Azirun, C.D. Chen & K. W. Lau. Distribution. Vietnam (Lam Dong and Nghe An). Remarks. This species is a species complex comprising 11 cytoforms, of which nine are reported from Thailand (Adler and Crosskey 2016). In Vietnam, two morphoforms (���a��� and ���b���) were recognized, both of which are morphologically distinguished from S. (S.) tani (= cytoform K) originally described from Peninsular Malaysia (Takaoka et al. 2015a). Morphoform ���a��� is chromosomally divided into two cytoforms (Adler et al. 2016) and is also shown to include an additional possible cryptic taxon by a DNA sequence-based analysis (Low et al. 2016). Simulium (Simulium) suoivangense Takaoka & Pham sp. nov. Simulium (Simulium) tani (complex): Morphoform ���b���: Takaoka et al., 2015a: 85 ���86. Morphoform ���b��� of S. (S.) tani (complex) reported from southern Vietnam (Takaoka et al. 2015a) is here described as a distinct species and a new name S. suoivangense is given. Female. Body length 2.4���2.6 mm. Head. Slightly narrower than thorax. Frons black, shiny with bright reflection when illuminated at certain angles, with several dark stout hairs along lateral margins; frontal ratio 1.3��� 1.4:1.0:1.2���1.3; frons:head ratio 1.0:3.5���4.0. Fronto-ocular area well developed, short, directed laterally, and rounded apically. Clypeus black, slightly shiny, moderately covered with dark-brown medium-long hairs though mediolongitudinal portion widely bare. Labrum 0.5���0.6 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres; antenna dark brown, except scape, pedicel and base of first flagellomere yellow. Maxillary palp with five segments, medium brown except segment 3 dark brown; proportional lengths of third, fourth, and fifth segments 1.0:1.2���1.3:2.6���2.8; third segment (Fig. 66 A) of moderate size, with long ellipsoidal sensory vesicle (0.5���0.6 times length of third segment) having medium-sized opening. Maxillary lacinia with 14��� 16 inner and 19 or 20 outer teeth. Mandible with 31 or 32 inner and 11 outer teeth. Cibarium (Fig. 66 B) with 82���90 minute processes near posterodorsal margin. Thorax. Scutum black, shiny with bright reflection when illuminated at certain angles, moderately covered with dark short fine hairs interspersed with several dark-brown long upright hairs on prescutellar area. Scutellum dark brown, shiny when illuminated at certain angles, covered with darkbrown upright long hairs. Postnotum brownish black, shiny when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, shiny when illuminated at certain angles, and bare. Legs. Foreleg: coxa whitish yellow; trochanter light brown with base whitish yellow; femur light to medium brown with apical cap dark brown; tibia medium brown except apical cap dark brown, with median outer surface widely white and with bright white sheen when illuminated at certain angles; tarsus black, with moderate dorsal hair crest; basitarsus greatly dilated, 4.3���4.6 times as long as its greatest width. Midleg: coxa dark brown with posterolateral surface brownish black; trochanter medium brown with base whitish yellow; femur medium to dark brown except apical cap brownish black; tibia medium brown except base yellowish white and apical cap brownish black, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus medium brown except basal three-fourths or two-thirds of basitarsus and base of second tarsomere yellowish white. Hind leg: coxa medium to dark brown; trochanter whitish yellow; femur dark brown except base whitish yellow; tibia medium to dark brown except base yellowish white and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus medium brown except little more than basal two-thirds of basitarsus and basal half of second tarsomere yellowish white; basitarsus (Fig. 66 C) nearly parallel-sided, 5.4���5.6 times as long as wide, and 0.8 and 0.7 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 66 C) moderately developed, nearly as long as wide, and 0.4 times as wide as greatest width of basitarsus; pedisulcus (Fig. 66 C) well developed; claw simple, without tooth. Wing. Length 1.7���2.0 mm. Costa with dark spinules and hairs; subcosta haired except apical half to one-fifth bare; basal section of radius bare; R1 with dark brown spinules and hairs; R2 with dark-brown hairs; hair tuft on base of radius dark brown; basal cell absent. Halter. White except basal portion darkened. Abdomen. Basal scale dark brown, with fringe of yellow hairs. Dorsal surface of abdomen medium brown to brownish black, with dark short hairs; tergite 2 shiny and silvery iridescent when illuminated at certain angles and tergites 6���9 shiny and iridescent when illuminated at certain angles. Ventral surface of segment 7 with pair of weakly sclerotized submedian sternal plates. Terminalia. Sternite 8 (Fig. 66 D) well sclerotized and bare medially, covered with 9���13 long and medium-long stout hairs and three to six short fine hairs on each side. Ovipositor valve (Fig. 66 D) nearly triangular, rounded posteromedially, membranous except inner margin weakly sclerotized, densely covered with microsetae together with seven to nine short fine hairs; inner margin nearly straight or sinuous or slightly concave medially. Genital fork (Fig. 66 E) of inverted-Y form; stem slender and well sclerotized; arms of moderate width, each with distinct projection directed forward from lateral ridge. Paraproct in ventral view (Fig. 66 F) pointed posteromedially, moderately concave anterolaterally, and with strongly sclerotized anteromedial surface bearing five sensilla; paraproct in lateral view (Fig. 66 G) somewhat produced ventrally and slightly posteriorly, 0.6 times as long as wide, covered with 18���22 medium-long stout hairs and numerous microsetae on lateral and ventral surfaces. Cercus in lateral view (Fig. 66 G) short, rounded posteriorly, 0.6 times as long as its greatest width, and covered with medium-long and short stout hairs. Spermatheca (Fig. 66 H) ovoidal, 1.2���1.3 times as long as wide, well sclerotized except duct and narrow area of juncture with duct unsclerotized, without discernible reticulate surface patterns; minute internal setae present; accessory ducts subequal in thickness to each other and slightly thicker than main duct. Male. Body length 2.5���2.7 mm. Head. Slightly wider than thorax. Upper eye medium brown, consisting of large facets in 17 or 18 vertical columns and in 18 horizontal rows. Clypeus black, thickly white pruinose, silvery shiny when illuminated at certain angles, covered with dark-brown hairs along and near lateral margins (most of central portion bare). Antenna composed of scape, pedicel and nine flagellomeres, brownish black except scape, pedicel and base of first flagellomere dark yellow to light brown; first flagellomere elongate, 1.5 times as long as second one. Maxillary palp grayish to dark brown, composed of five segments with proportional lengths of third, fourth, and fifth segments 1.0:13:2.7���2.8; third segment (Fig. 67 A) widened apically; sensory vesicle (Fig. 67 A) small (0.2 times as long as third segment), ellipsoidal, and with small opening. Thorax. Scutum black, with white pruinose pattern, i.e., anterior pair of triangular spots (not sharply pointed posteriorly) on shoulders extended posteriorly along lateral margins but not connected to large transverse spot entirely covering prescutellar area; these pruinose areas silvery or bluish iridescent when illuminated at certain angles; scutum uniformly and densely covered with brassy recumbent short hairs interspersed with dark-brown long upright hairs on prescutellar area. Scutellum brownish black, with several dark-brown long upright hairs. Postnotum brownish black, white pruinose when illuminated at certain angles and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, thinly white pruinose and shiny when illuminated at certain angles, and bare. Legs. Color as in female except hind tibia with basal small portion yellow, and hind basitarsus yellowish white on basal half or little less. Fore basitarsus greatly dilated, 5.4���6.1 times as long as its greatest width. Hind basitarsus (Fig. 67 B) much enlarged, gradually widened from base to apical two-fifths, then slightly narrowed toward apex, 3.6���3.8 times as long as its greatest width, and 0.8���0.9 and 0.9 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 67 B) small, nearly as long as wide, 0.2 times as wide as greatest width of basitarsus; pedisulcus (Fig. 67 B) well developed. Halter. White except basal portion darkened. Wing. Length 1.6���1.7 mm. Other characters as in female except subcosta bare. Abdomen. Basal scale brownish black, with fringe of pale (though basally dark) long hairs. Dorsal surface of abdomen brownish black to black, with dark short hairs; segments 2 and 5���7 each with pair of silvery or bluish iridescent spots dorsolaterally, those on segment 2 broadly connected in middle to each other. Genitalia. Coxite in ventral view (Fig. 67 C) nearly quadrate, covered with stout hairs near posterior margin. Style in ventral view (Fig. 67 C) elongate, gradually tapered from base to middle, then nearly parallel-sided, with apical spine; style in ventrolateral view (Fig. 67 D) elongate, 2.6 times as long as its greatest width at basal one-third, slightly widened from base to basal one-third, much tapered toward apical one-third, then slightly widened toward tip; style in medial view (Fig. 67 E) 1.6 times as long as coxite, much produced dorsally near base and with 8���12 small cone-like spines on dorsal surface. Ventral plate in ventral view (Fig. 67 C) well sclerotized, with body subquadrate (though rounded on each posterolateral corner), 0.7 times as long as wide, posterior margin somewhat convex, and with round projection directed ventrally which is covered with many minute setae; arms directed forward and somewhat divergent from each other; ventral plate in lateral view (Fig. 67 F) with posterior margin serrated along basal two-thirds; ventral plate in caudal view (Fig. 67 G) rounded ventrally, with lateral margin serrated along basal two-thirds, with numerous setae on posterior surface except both areas of dorsolateral corners bare. Median sclerite (Fig. 67 F, H) plate-like, gradually widened from base toward near apex, with round apex, brown basally, but not sclerotized apically. Paramere (Fig. 67 I) with several distinct hooks and several smaller ones. Aedeagal membrane (Fig. 67 J) moderately covered with minute setae, and with moderately sclerotized dorsal plate in form of horizontal bar (Fig. 67 K). Abdominal segment 10 (Fig. 67 L, M) with four to eight hairs on lateral surface and one to three hairs on ventral surface on each side. Cercus (Fig. 67 L, M) small, rounded, with seven to ten distinct hairs. Pupa. Body length 2.0��� 2.5 mm. Head. Integument including antennal sheaths yellow; frons moderately covered with tubercles, of which some or most having minute secondary projections, and with two pairs of unbranched short trichomes; face with pair of unbranched short trichomes slightly longer and stouter than frontal trichomes. Thorax. Integument yellow, moderately covered with tubercles, of which some on anterodorsal surface have minute secondary projections; thorax on each side with two short anterodorsal trichomes, two short anterolateral trichomes (one sometimes slightly thinner and shorter than other), one short mediolateral trichome, and three short ventrolateral trichomes (one slightly shorter and thinner than two others); all trichomes unbranched. Gill (Fig. 68 A) with six slender thread-like filaments in three pairs (one dorsal, one middle and one ventral); no common basal stalk and basal fenestra small; all pairs short-stalked, and stalks of dorsal and ventral pairs lying at angle of 70 degrees when viewed laterally; filaments decreasing in length from dorsal to ventral, with longest dorsal filament 1.6���1.8 mm long and shortest ventral filament 1.1���1.5 mm long; relative thickness of filaments from dorsal to ventral when compared basally 1.0:0.9:0.9:0.8:0.9:0.7; all filaments medium brown, tapered toward basal half, then nearly of same thickness up to tip, with distinct annular ridges and furrows, and densely covered with minute tubercles. Abdomen. Dorsally, all segments unpigmented except segment 1, basal half of segment 2, and segment 9 light yellowish; segment 1 with one unbranched short seta on each side; segment 2 with one unbranched short seta and five spinous short setae on each side; segments 3 and 4, each with four distinct hooked spines and one unbranched spinous short seta on each side; segments 5 and 6 lacking spine-combs; segments 7���9 each with distinct spine-combs in transverse row and comb-like groups of minute spines on each side; segment 9 without terminal hooks. Ventrally, segments 4���8 unpigmented and segment 9 somewhat yellowish; segments 4���8 each with comb-like groups of minute spines; segment 4 with one unbranched stout hooklet and few slender minute setae on each side; segment 5 with pair of bifid stout hooks submedially and few unbranched short setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer stout hooks somewhat separated from each other, and few unbranched short setae on each side. Grapnel-shaped hooklets absent on each side of segment 9. Cocoon. Wall-pocket-shaped, moderately woven, thin, ochreous, and not extended ventrolaterally; individual threads visible; 2.7���3.1 mm long by 1.0��� 1.2 mm wide. Mature larva. Body length 4.6���5.0 mm. Thoracic segment 1 and abdominal segments 1���4 each encircled by broad dark-gray transverse band and abdominal segments 5���9 dark gray on dorsal and dorsolateral surfaces; thoracic segments 2 and 3 often light gray on dorsal surface and dark gray on ventral surface, and abdominal segments 4���6 each with dark mediolongitudial band on ventral surface; abdominal segments 6 and 7 each with thin grayish transverse band ventrally. Head. Cephalic apotome yellow (though rarely dark yellow) with small medial area near posterior margin sometimes darkened; head spots almost indistinct or faintly positive. Lateral surface of head capsule yellow except eye-spot region whitish and areas anterior and posterior to eye-spot region somewhat darkened. Ventral surface of head capsule (Fig. 68 D) yellow, though often widely darkened medially; long spot on each side of postgenal cleft clearly negative. Antenna composed of three articles and apical sensillum, slightly longer than stem of labral fan; length ratio of three articles (from base to tip) 1.0:0.9���1.0:0.7���0.8. Labral fan with 37���41 main rays. Mandible (Fig. 68 B) with mandibular serrations composed of two teeth (one medium-sized, one small); main tooth at right angle against mandible on apical side; supernumerary serrations absent; comb-teeth decreasing in length from first to third. Hypostoma (Fig. 68 C) with nine anterior teeth, of which corner teeth most prominent, slightly longer than median tooth, and intermediate teeth shortest; lateral margins serrate apically; four or five hypostomal bristles nearly parallel to lateral border on each side. Postgenal cleft (Fig. 68 D) arrow-head shaped, long, 4.2���5.3 times length of postgenal bridge; subesophageal ganglion not pigmented. Cervical sclerite on each side composed of one medium-brown elongate piece and one light-brown elliptical piece, not fused to occiput. Thorax and Abdomen. Histoblast of pharate pupal gill with six short filaments. Thoracic and abdominal cuticle almost bare except few posterior segments moderately covered with colorless minute setae dorsally, and last segment of abdomen moderately covered with colorless short setae on each side of anal sclerite. Rectal scales present. Rectal organ compound, each lobe with 10���12 finger-like secondary lobules. Anal sclerite X-shaped, with short broad anterior arms 0.6���0.8 times as long as posterior ones; one or two sensilla on juncture area; five sensilla posterior to posterior arms. Last abdominal segment somewhat swollen laterally but lacking ventral papillae. Posterior circlet with 75���80 rows of hooklets with up to 15 or 16 hooklets per row. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 45, Holotype, Simulium (S.) suoivangense , Female, coll. Vietnam, 24-IV-2014, Takaoka et al.], reared from a pupa collected from a river (width 4���6 m, water temperature 18.0˚C, exposed to the sun, elevation 1,452 m, 12˚10���56.408���N/108˚40���48.152���E), moderately flowing in open land, Suoi Vang, Lac Duong District, Lam Dong Province, southern Vietnam, 24-IV-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. PARATYPES: 11 females and five males and two mature larvae, same data as those of the holotype, labeled in each vial as [UMSRP: Vietnam 0 45, Paratype, Simulium (S.) suoivangense , coll. Vietnam, 24- IV-2014, Takaoka et al.]; 10 females and seven males (all reared from pupae) in 80% ethanol, labeled in each vial as [UMSRP: Vietnam 0 45, Paratype, Simulium (S.) suoivangense , Male, coll. Vietnam, 9-XII-2015, Takaoka et al.], collected from a river (width 4���5 m, depth 20���30 cm, bottom of pebbles, water temperature 15.0˚C, partially shaded, elevation 223 m, 18˚58���03.270���N/104˚48���07., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 147-153, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Davies, D. M. (1995) The Black Flies (Diptera: Simuliidae) of West Malaysia. Kyushu University Press, Fukuoka, viii + 175 pp.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96.","Adler, P. H. & Crosskey, R. W. (2016) World Blackflies (Diptera: Simuliidae): A Comprehensive Revision of the Taxonomic and Geographical Inventory [2016]. 126 pp. Available from: https: // www. clemson. edu / cafls / biomia / pdfs / blackflyinventory. pdf (accessed 10 May 2016)"]}

Simulium (Simulium) quinquestriatum (Shiraki, 1935) Stilboplax 5- striatum Shiraki, 1935: 27 ���33 (Female). Simulium (Simulium) quinquestriatum (Shiraki), Anonymous, 1974: 192; Takaoka 1977: 205 ���209 (Female, male, pupa and larva). Distribution. China, Korea, Japan, Taiwan, Thailand and Vietnam (Bac Giang, Bac Thai, Ha Tay, Hoa Binh, Lang Son and Yen Bai). Remarks. Simulium (S.) quinquestriatum was originally described from Taiwan (Shiraki 1935). It was recorded from six provinces in northern Vietnam by Pham (1998, 1999)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 118, DOI: 10.5281/zenodo.571608, {"references":["Shiraki, T. (1935) Simuliidae of the Japanese Empire. Memory of Faculty of Science and Agriculture Taihoku Imperial University, 16, 1 - 90.","Takaoka, H. (1977) Studies on blackflies of the Nansei Islands, Japan (Simuliidae; Diptera). III. On six species of the subgenus Simulium Latreille. Japanese Journal of Sanitary Zoology, 28 (2), 193 - 217.","Pham, X. D. (1998) New records of six black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 49 (2), 121 - 123.","Pham, X. D. (1999) Additional records of three black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 50 (4), 335 - 336."]}

Simulium (Gomphostilbia) parahiyangum Takaoka & Sigit, 1992 Simulium (Gomphostilbia) parahiyangum Takaoka & Sigit, 1992: 135 –142 (Female, male, pupa and larva). Specimens examined. Seven females, nine males (all reared from pupae), and six mature larvae, collected from a slow-flowing stream (width 1.0 m, depth 5–10 cm, bottom sandy, water temperature 18.0˚C, shaded, elevation 80 m, 19˚30’46.589”N/105˚09’10.470”E), Chau Dinh, Quy Chau, Nghe An Province, northern Vietnam, 11-XII-2015, by H. Takaoka, M. Sofian-Azirun, C.D. Chen & K.W. Lau. Distribution. Java, Sumatra, Malaysia, Thailand, Assam and Vietnam (Nghe An) (New record). Remarks. The male of this species collected from Vietnam differs from that of S. (G.) parahiyangum from Java by the number of upper-eye facets in 14 vertical columns and 14 (rarely 15) horizontal rows (in 17 vertical columns and 15 horizontal rows in the original description) (Takaoka and Sigit 1992).

Simulium (Simulium) thailandicum Takaoka & Suzuki, 1984 Simulium (Simulium) thailandicum Takaoka & Suzuki, 1984: 37 ���38 (Male and pupa). Distribution. China (Yunnan), Thailand, and Vietnam (Bac Giang, Ha Tay, Lang Son and Yen Bai). Remarks. Simulium (S.) thailandicum was originally described from Thailand (Takaoka and Suzuki 1984). It was recorded from four provinces in Vietnam by Pham (1998, 1999). Simulium (Simulium) tavanense Takaoka & Sofian-Azirun sp. nov. Female. Body length 2.2���2.4 mm. Head. Slightly narrower than thorax. Frons black, shiny with bluish reflection when illuminated at certain angles, with several dark stout hairs along lateral margins and several hairs just above lower margin; frontal ratio 1.4:1.0:1.2; frons:head ratio 1.0:3.6. Fronto-ocular area well developed, short, directed laterally, and rounded apically. Clypeus brownish-black, slightly shiny and gray pruinose when illuminated at certain angles, moderately covered with dark-brown medium-long hairs (though mediolongitudinal portion of upper half widely bare). Labrum 0.7 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, medium to dark brown except scape, pedicel, and first and second flagellomeres yellow when viewed anteriorly (medium brown to dark brown except scape, pedicel and base of first flagellomere yellow when viewed posteriorly). Maxillary palp with five segments, medium brown except first and second segments ochreous or light brown, and third segment dark brown; proportional lengths of third, fourth, and fifth segments 1.0:1.0:2.5; third segment (Fig. 52 A) of normal size, with medium-sized ellipsoidal sensory vesicle (0.42 times length of third segment) having opening of moderate size. Maxillary lacinia with 12 inner and 13 or 14 outer teeth. Mandible with 23 inner and 13 outer teeth. Cibarium (Fig. 52 B) with 31 minute processes near posterodorsal margin. Thorax. Scutum black, shiny, densely covered with whitish-yellow to yellow recumbent short hairs and sparsely with several dark-brown long upright hairs on prescutellar area; scutum gray pruinose with five non-pruinose longitudinal vittae (one medial, two submedial, and two lateral), medial and submedial vittae well defined from anterior margin to posterior portion and submedial and lateral vittae united widely near anterior margin), all vittae united with transverse non-pruinose band on prescutellar area, when illuminated in front and viewed dorsally; scutum gray pruinose except four non-pruinose longitudinal vittae, when illuminated posteriorly and viewed dorsally. Scutellum medium brown, covered with dark-brown upright long hairs and yellow short hairs. Postnotum brownish black, shiny, white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum brownish black, longer than deep, shiny, white pruinose when illuminated at certain angles, and bare. Legs. Foreleg: coxa and trochanter yellowish white; femur light brown except inner surface of basal portion widely whitish yellow, and apical tip medium brown; tibia dark brown to brownish black; tarsus black, with moderate dorsal hair crest; basitarsus greatly dilated, 5.3���5.9 times as long as its greatest width. Midleg: coxa brownish black; trochanter light brown except base whitish; femur medium brown except apical cap dark brown; tibia light to medium brown with apical cap dark brown and base whitish, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus light to medium brown except basal five-sixths of basitarsus and base of second tarsomere whitish. Hind leg: coxa brownish black; trochanter yellowish white; femur dark brown to brownish black except base whitish yellow; tibia dark brown except base yellowish white and with whitish sheen on basal half or more of posterior surface when illuminated at certain angles; tarsus medium brown except basal two-thirds of basitarsus and basal half of second tarsomere yellowish white; basitarsus (Fig. 52 C) nearly parallel-sided, 6.3 times as long as wide, and 0.7 and 0.6���0.7 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 52 C) moderately developed, slightly shorter than wide, and 0.4 times as wide as greatest width of basitarsus; pedisulcus (Fig. 52 C) well developed. Claw simple, without tooth. Wing. Length 2.2 mm. Costa with dark spinules and hairs; subcosta haired except near apex bare; basal section of radius with four or five hairs on apical half or little more; R1 with dark brown spinules and hairs; R2 with dark-brown hairs; hair tuft on base of radius dark brown; basal cell absent. Halter. White except base darkened. Abdomen. Basal scale dark brown, with fringe of pale hairs. Dorsal surface of abdomen medium brown to brownish black, with light to dark-brown short hairs; tergite 2 shiny and silvery iridescent when illuminated at certain angles and tergites 6���9 shiny. Ventral surface of seventh segment with pair of weakly sclerotized submedian sternal plates. Terminalia. Sternite 8 (Fig. 52 D) with posterior margin concave medially in form of reversed-U shape, bare medially, with 15���20 dark-brown medium-long to long stout hairs and 9���11 yellow short to medium-long hairs on each lateral surface. Ovipositor valve (Fig. 52 D) triangular, with ventrally produced lobe near inner margin, membranous except narrow area along inner margin slightly sclerotized, covered with 23���26 short yellow hairs and numerous microsetae; inner margins slightly sinuous, somewhat separated from each other. Genital fork (Fig. 52 E) of inverted-Y form, with narrow well-sclerotized stem; arms of moderate width, each with moderately sclerotized lateral portion. Paraproct in ventral view (Fig. 52 F) rounded, subequal in length to greatest width, strongly pigmented on anterior surface, with 41���44 yellow and dark short to medium-long hairs on lateral and ventral surfaces, and with six to eight short sensilla on anteromedial surface; paraproct in lateral view (Fig. 52 G) nearly 0.5 times as long as wide, and much protruding ventrally beyond ventral margin of cercus. Cercus in lateral view (Fig. 52 G) short, 0.5 times as long as wide, with numerous medium-long hairs, and rounded posteriorly. Spermatheca (Fig. 52 H) nearly ovoid, 1.2 times as long as greatest width, well sclerotized except portion of junction with duct widely unsclerotized, without definite reticulate patterns on its surface; internal setae present; accessory ducts subequal in thickness to each other, and slightly thicker than major duct. Male. Body length 2.9 mm. Head. Nearly as wide as thorax. Upper-eye large facets in 18 vertical columns and 19 horizontal rows. Clypeus black, thickly white pruinose and iridescent when illuminated at certain angles, with dark-brown hairs along and near lateral margins (most of central portion bare). Antenna composed of scape, pedicel and nine flagellomeres, dark brown except scape and pedicel light brown and base of first flagellomere yellow; first flagellomere elongate, 1.6 times length of second one. Maxillary palp with five segments, mediumbrown except first and second segments ochreous and fifth segment grayish light-brown; proportional lengths of third, fourth, and fifth segments 1.0:1.3:2.9; third segment (Fig. 53 A) of normal size; sensory vesicle (Fig. 53 A) ellipsoidal, 0.2���0.3 times length of third segment, and with small opening. Thorax. Scutum black, with whitishpruinose pattern, i.e., anterior pair of large spots on shoulders extended posteriorly along lateral margins and connected to large transverse spot entirely covering prescutellar area, anterior pair of large spots divided into anterior half and posterior half, either of which disappears depending on direction of lights; all these spots brilliantly iridescent when illuminated at certain angles; scutum uniformly and moderately covered with yellow recumbent short hairs and with several dark-brown long upright hairs on prescutellar area. Scutellum medium brown, with dark-brown long upright hairs and yellow short hairs. Postnotum brownish black, shiny and whitish pruinose when illuminated at certain angles and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, and bare. Legs. Foreleg: coxa yellowish white; trochanter light brown; femur light brown with apical tip medium brown; tibia medium brown to brownish black; tarsus black, with moderate dorsal hair crest; basitarsus greatly dilated, 5.8���6.3 times as long as its greatest width. Midleg: coxa brownish black; trochanter medium brown except base whitish; femur medium brown with apical cap dark brown; tibia medium to dark brown except extreme base yellowish white; tarsus medium brown except basal two-thirds of basitarsus yellowish white. Hind leg: coxa brownish black; trochanter yellowish white; femur medium brown except base whitish yellow and apical cap dark brown; tibia dark brown to brownish black except base yellowish white; tarsus medium brown except basal half of basitarsus and basal one-third of second tarsomere whitish yellow; basitarsus (Fig. 53 B) enlarged, slightly widened toward apical one-third, then slightly narrowed, 3.9���4.0 times as long as wide, and 0.8��� 0.9 and 0.9���1.0 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 53 B) developed, small, slightly shorter than its basal width, and 0.3 times as wide as greatest width of basitarsus; pedisulcus (Fig. 53 B) well developed. Wing. Length 2.3 mm. Other characters as in female except subcosta with hairs on basal half or little more, and basal portion of radius with four or five hairs on apical half or little less. Halter. White except base darkened. Abdomen. Basal scale brownish black, with fringe of dark-brown long hairs. Dorsal surface of abdomen dark brown to brownish black, moderately covered with dark-brown short to mediumlong hairs; segments 2, 5, 6 and 7 each with pair of whitish pruinose spots (brilliantly iridescent when illuminated at certain angles) dorsolaterally, those on segment 2 broadly connected in middle to each other. Genitalia. Coxites, styles and ventral plate in ventral view as in Fig. 53 C; coxite in ventrolateral view (Fig. 53 D) rectangular, 0.76 times as long as wide; style in ventrolateral view (Fig. 53 E) 1.6 times length of coxite, 3.4 times as long as greatest width near base, somewhat narrowed to little more than basal half, then slightly widened and nearly parallel-sided, with subapical spine; style in medial view (Fig. 53 F) somewhat flattened dorsoventally, with short basal protuberance directed dorsomedially, with several cone-like spines along its anterior margin. Ventral plate in ventral view (Fig. 53 C) with body broad, with lateral margins gently convex, anterior margin deeply concave, and posterior margin nearly straight or slightly concave; body bearing prominent median process sharply narrowed to round tip; body covered with minute setae medially; arms short, stout, divergent from base; ventral plate in lateral view (Fig. 53 G) with median process abruptly bent ventrally at nearly right angle; ventral plate in caudal view (Fig. 53 H) in form of equilateral triangle, and bare. Median sclerite in lateral view (Fig. 53 G) arising anterior to anteromedian portion of ventral plate, and in middle curved dorsally; median sclerite in caudal view (Fig. 53 I) nearly parallel-sided. Paramere in caudal view (Fig. 53 J) enlarged basally, with several hooks apically. Aedeagal membrane in caudal view (Fig. 53 K) sparsely covered with minute setae; dorsal plate not sclerotized. Abdominal segment 10 (Fig. 53 L, M) with two to five hairs and 10���12 shorter hairs on ventral surface and two to seven hairs on lateral surface; cercus (Fig. 53 L, M) small, with 16 or 17 distinct hairs. Pupa. Body length 2.5���3.0 mm. Head. Integument light ochreous, moderately covered with relatively large tubercles having few to several secondary projections on frons (Fig. 54 A), and moderately with round or cone-like small ones without secondary projections on face; frons with two pairs of unbranched or bifid short to mediumlong trichomes with straight apices (Fig. 54 B); face with pair of unbranched medium-long trichomes with straight apices (Fig. 54 C), as long as or longer or shorter than frontal trichomes. Thorax. Integument light ochreous, moderately covered with relatively large tubercles (similar to those on frons) except lateral surfaces and dorsal surface of posterior half of thorax moderately covered with relatively smaller round or cone-like tubercles; thorax on each side with three long trichomes with two to five branches (Fig. 54 D) anterodorsally, two bifid or trifid long trichomes (Fig. 54 E) anterolaterally, one unbranched or bifid medium-long trichome (Fig. 54 F) mediolaterally, and three trichomes with coiled or straight apices (two unbranched or bifid long, one bifid short) (Fig. 54 G) ventrolaterally. Gill (Fig. 54 H) with 10 thread-like filaments arranged as 2+[(1+2)+(2+1)]+2 from dorsal to ventral; dorsal and ventral pairs with short stalk, two middle triplets with short stalk; all filaments subequal in length (0.7��� 1.0 mm) and thickness, though ventral filament of ventral pair slightly thicker than other filaments (relative thickness of filaments from dorsal to ventral when compared basally 1.0:1.0:0.8���1.0:0.8���0.9:0.9���1.0:0.8 ���1.0:0.8��� 1.0:1.0���1.1:1.0���1.3:1.1���1.3); all filaments light brown, covered with sharply-defined annular ridges and furrows and densely covered with minute tubercles, relatively larger ones on ridges and smaller one on interridges. Abdomen. Dorsally, all segments nearly transparent except segments 1 and 9 light yellow; segment 1 without tubercles, with one unbranched short seta (Fig. 54 I) on each side; segment 2 with one unbranched short seta and five minute setae, of which four are stout and one slender (Fig. 54 J) on each side; segments 3 and 4 each with four distinct hooks and one short spinous seta on each side; all setae and hooks unbranched; segments 5, 6, 7 and 9 lacking spine-combs; segment 8 with distinct spine-combs in transverse row; segments 6���9 each with comb-like groups of minute spines on each side; segment 9 with pair of cone-like terminal hooks (Fig. 54 K). Ventrally, all segment unpigmented except segment 9 yellowish; segments 4���8 each with comb-like groups of minute spines; segment 5 with pair of bifid stout hooklets submedially and few unbranched minute setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer stout hooklets somewhat separated from each other and few unbranched minute setae on each side. Grapnel-shaped hooklets absent on each side of segment 9. Cocoon (Fig. 54 L). Light ochreous, shoe-shaped, with several small to large open spaces anterolaterally on each side; posterior half with floor; posterior half thickly woven and individual threads almost invisible; 3.0��� 3.6 mm long by 1.2���1.5 mm wide; height 0.8���1.0 mm. Mature larva. Body length 5.3���6.0 mm. Body dark gray. Abdomen in lateral view gradually widened from segment 1 to segment 7, then narrowed to segment 9. Head. Cephalic apotome (Fig. 55 A) whitish yellow on anterior two-fifths, dark yellow to ochreous on posterior three-fifths, with area along posterior margin darkened; head spots obscured except mediolateral spots often faintly negative; lateral surface of head capsule yellow to ochreous (in one larva, widely medium brown), except eye-spot region whitish and areas above and posterior to eye-spot region darkened; eyebrow distinct; spots near posterior margin and below eye-spot region obscured or faintly negative; ventral surface of head capsule (Fig. 55 B) yellow to ochreous; elongate spots on each side of postgenal cleft faintly negative. Antenna composed of three articles and apical sensillum, slightly longer than stem of labral fan; length ratio of three articles (from base to tip) 1.0:1.3:0.5���0.7. Labral fan with 53���56 primary rays. Mandible (Fig. 55 C) with mandibular serration composed of two teeth (one medium-sized, one small); main tooth at right angle against mandible on apical side; comb-teeth gradually decreased in length from first to third; supernumerary serrations absent (though one minute tooth present between two mandibular teeth in left mandible of one larva). Hypostoma (Fig. 55 D) with nine anterior teeth, of which median and corner teeth subequal in length to each other, followed by three intermediate teeth on each side; lateral margins serrate apically; six or seven hypostomal bristles divergent posteriorly from lateral border on each side. Postgenal cleft (Fig. 55 B) large, rounded, 3.7���4.0 times length of postgenal bridge; sheath of subesophageal ganglion weakly or moderately pigmented. Cervical sclerites on each side composed of light-brown elliptical piece, not fused to occiput. Thorax and Abdomen. Histoblast of pharate pupal gill with 10 thread-like slender filaments. Thoracic cuticle sparsely covered with minute colorless setae. Abdominal segments 1���7 each with pair of cone-like dorsolateral protuberances (Fig. 55 E). Abdominal cuticle sparsely covered with minute colorless setae (Fig. 55 E), and moderately covered with short colorless setae on each side of anal sclerite. Rectal scales present. Rectal organ of three lobes, each with 12���15 finger-like secondary lobules. Anal sclerite X-shaped, with short broad anterior arms 0.65 times length of posterior ones and with forked apices; three or four sensilla on base of anal sclerite; four sensilla posterior to posterior arms. Last abdominal segment not bulged laterally and lacking ventral papillae. Posterior circlet with 134���138 rows of hooklets with up to 21���23 hooklets per row. Type material. HOLOTYPE: Male (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 39, Holotype, Simulium (S.) tavanense , Male, coll. Vietnam, 21-XII-2014, Takaoka et al.], collected from a stream (width 1.0 m, depth 8 cm, bottom of pebbles, water temperature 13˚C, exposed to the sun, elevation 1,048 m, 22˚18���33.255������N/103˚53���12.129������E), flowing near forest, Tavan, Sapa, Lao Cai Province, northern Vietnam, 21-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. PARATYPES. One male (with its associated pupal exuviae and cocoon) and three mature larvae, in 80% ethanol, same data as those of the holotype labeled in a vial as [UMSRP: Vietnam 0 39, Paratype, Simulium (S.) tavanense , coll. Vietnam, 21-XII-2014, Takaoka et al.]; two females (all with their associated pupal exuviae and cocoons) in 80% ethanol, labeled in each vial as [UMSRP: Vietnam 0 39, Paratype, Simulium (S.) tavanense , Female, coll. Vietnam, 21-XII-2014, Takaoka et al.], collected from a stream (width 1.0 m, depth 7 cm, bottom sandy, water temperature 17˚C, exposed to the sun, elevation 999 m, 22˚18���23.788������N/103˚53���42.780������E), slowly flowing in a grassland, Tavan, Sapa, Lao Cai Province, northern Vietnam, 21-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. Biological notes. The pupae and larvae of this new spe, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 118-125, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Suzuki, H. (1984) The blackflies (Diptera: Simuliidae) from Thailand. Japanese Journal of Sanitary Zoology, 35 (1), 7 - 45.","Pham, X. D. (1998) New records of six black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 49 (2), 121 - 123.","Pham, X. D. (1999) Additional records of three black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 50 (4), 335 - 336.","Takaoka, H. & Davies, D. M. (1996) The Black Flies (Diptera: Simuliidae) of Java, Indonesia. Bishop Museum Bulletin in Entomology 6. Bishop Museum Press, Honolulu, Hawaii, viii + 81 pp.","Brunetti, E. (1911) New Oriental Nematocera. Record of Indian Museum, 4, 282 - 288.","Puri, I. M. (1932 d) Studies on Indian Simuliidae. Part V. Species and varieties of the striatum series. Indian Journal of Medical Research, 20, 515 - 532.","Shiraki, T. (1935) Simuliidae of the Japanese Empire. Memory of Faculty of Science and Agriculture Taihoku Imperial University, 16, 1 - 90.","Huang, Y. T. & Takaoka, H. (2008) Simulium (Simulium) pingtungense, a new black fly (Diptera: Simuliidae) from Taiwan. Medical Entomology and Zoology, 59 (4), 309 - 317.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 a) New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam. Zootaxa, 3838 (3), 347 - 366. https: // doi. org / 10.11646 / zootaxa. 3838.3.6"]}

Simulium (Simulium) doipuiense Takaoka & Choochote, 2005 (complex) Simulium (Simulium) doipuiense Takaoka & Choochote, 2005c: 106 –110 (Female, male, pupa and larva). Simulium (Simulium) rufibasis (not Brunetti): Takaoka et al., 2014b: 747. Specimens examined. One female, three males (all reared from pupae), collected from a stream (width 1.0 m, depth 7 cm, streambed sandy, water temperature 17˚C, exposed to the sun, elevation 999 m, 22˚18’23.788’’N/ 103˚53’42.780’’E), slowly flowing in a grassland, Tavan, Sapa, Lao Cai Province, northern Vietnam, 21-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau; one female, collected while flying around a human, along a road traversing a mountain slope (elevation 997 m, 21˚28’104”N/105˚51’38.687”E), Tam Dao National Park, Vinh Phuc Province, Vietnam, 9-IX-2013, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau. Distribution. Vietnam (Lao Cai and Vinh Phuc). Remarks. Simulium (S.) doipuiense was described from Thailand (Takaoka and Choochote 2005c) and was shown to be a species complex consisting of two cytoforms (A and B) by chromosome analysis (Tangkawanit et al. 2009). According to the original description (Takaoka and Choochote 2005c), the female of this species is characterized by having a pair of clustered medium-long hairs on the ventral surface of abdominal segment 7, antenna dark brown except the scape, pedicel and first flagellomere yellow, scutum covered with yellow short hairs, hind tibia yellowish white except the apical two-fifths medium to dark brown, and stem of the genital fork without a round apex. The females collected from Vietnam are almost identical to those of S. (S.) doipuiense from Thailand except the following numerical differences (characters of S. (S.) doipuiense from Thailand in parentheses): the relative length of the height of the frons against its narrowest width 1.1 (1.3), relative length of the fore basitarsus against its greatest width 5.1 (4.9), relative width of the hind basitarsus against the hind tibia and femur 0.8 (0.7) and 0.7(0.6), respectively. The males from Vietnam are almost identical to those of S. (S.) doipuiense from Thailand including the number of upper-eye facets in 17 or 18 vertical columns and 18 horizontal rows and the fewer number of spines on the basal protuberance of the style (only several spines), but there is a difference in the relative length of the fore basitarsus against its greatest width (6.7–7.1 in the males from Vietnam versus 5.9–6.1 in those from Thailand). The pupae from both countries are almost identical in many characters including the frons moderately covered with round tubercles. The female collected from Tam Dao National Park previously reported as S. (S.) rufibasis Brunetti by Takaoka et al. (2014b) was reexamined. Our morphological examination shows that the female differs from that of S. (S.) rufibasis by the antenna dark brown except the scape, pedicel and the base of the first flagellomere yellow, scutum covered with yellow short hairs and hind basitarsus whitish yellow on the basal two-thirds and darkened on the rest. According to the redescription of Puri (1932a), the female of S. (S.) rufibasis has the antennae almost entirely darkened, scutum with brassy short hairs and hind basitarsus whitish yellow on the basal one-third to half and darkened on the rest. The characters of the female are most similar to those of S. (S.) doipuiense, though its hind tibia is yellowish white on the basal half and darkened on the rest, slightly differing from the color of the hind tibia of S. (S.) doipuiense from Thailand which is yellowish white on the basal three-fifths and darkened on the rest. The female collected from Tam Dao National Park is here treated as S. (S.) doipuiense (complex). Simulium (Simulium) fuscicoxae Takaoka & Ya’cob sp. nov. Simulium (Simulium) rufibasis (not Brunetti): Takaoka et al., 2015a: 85. The female and its associated pupal exuviae and cocoon previously reported from Lam Dong Province, southern Vietnam as S. (S.) rufibasis were reexamined. The result shows that this species is distinguished from S. (S.) rufibasis and other related species. It is here described as a new species. Female. Body length 2.0 mm. Head. Slightly narrower than thorax. Frons black, shiny, with several dark stout hairs along lateral margins; frontal ratio 1.3:1.0:1.2; frons:head ratio 1.0:3.8. Fronto-ocular area well developed, short, directed laterally, and rounded apically. Clypeus black, grayish pruinose, shiny, moderately covered with dark-brown medium-long hairs though mediolongitudinal portion of upper half widely bare. Labrum 0.68 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, brownish black except scape and pedicel light to medium brown and base of first flagellomere dark yellow. Maxillary palp with five segments, medium brown except third segment dark brown; proportional lengths of third, fourth, and fifth segments 1.0:1.2:2.2; third segment (Fig. 56 A, B) of moderate size, with medium-sized ellipsoidal sensory vesicle (0.3 times length of third segment) having large opening. Maxillary lacinia with 13 or 14 inner and 15 or 16 outer teeth. Mandible with 26 inner and 12 outer teeth. Cibarium (Fig. 56 C) with 82 minute processes, of which several are vestigial, near posterodorsal margin. Thorax. Scutum black, shiny, white pruinose when illuminated at certain angles, moderately covered with dark short fine hairs interspersed with several dark-brown long upright hairs on prescutellar area. Scutellum dark brown, covered with dark-brown upright long and short hairs. Postnotum black, shiny and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, shiny and white pruinose when illuminated at certain angles, and bare. Legs. Foreleg: coxa light brown; trochanter medium brown with base whitish; femur medium brown with apical cap dark; tibia whitish except apical cap dark brown and base light brown, with median outer surface widely white and with bright white sheen when illuminated at certain angles; tarsus brownish black, with moderate dorsal hair crest; basitarsus greatly dilated, 5.1 times as long as its greatest width. Midleg: coxa brownish black; trochanter medium except basal extreme whitish; femur medium brown except apical cap dark brown; tibia light brown except basal two-fifths whitish and apical cap dark brown, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus light to medium brown except basal half of basitarsus whitish. Hind leg: coxa dark brown; trochanter light brown; femur medium to dark brown except base light brown; tibia (Fig. 56 D) medium to dark brown except basal two-fifths white and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus medium brown except little more than basal half of basitarsus (though base light brown) and basal half of second tarsomere white; basitarsus (Fig. 56 E) nearly parallel-sided, 5.4 times as long as wide, and 0.8 and 0.7 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 56 E) moderately developed, little shorter than wide, and 0.4 times as wide as greatest width of basitarsus; pedisulcus (Fig. 56 E) well developed; claw simple, without tooth. Wing. Length 1.9 mm. Costa with dark spinules and hairs; subcosta haired except apical half bare; basal section of radius bare; R1 with dark spinules and hairs; R2 with dark hairs; hair tuft on base of radius dark brown; basal cell absent. Halter. White except base darkened. Abdomen. Basal scale medium brown, with fringe of dull hairs. Dorsal surface of abdomen medium brown to brownish black, with light to dark brown short hairs; tergite 2 and 6–9 shiny when illuminated at certain angles. Ventral surface medium brown to brownish black; segment 7 with pair of submedian sternal plates each bearing 18 or 19 stout medium-long to long hairs, of which seven or eight hairs in cluster (Fig. 56 F). Terminalia. Sternite 8 (Fig. 56 G) well sclerotized and bare medially, covered with eight to ten long and medium-long stout hairs and few short fine hairs on each side. Ovipositor valve (Fig. 56 G) nearly tongue-like, rounded posteromedially, membranous except inner margin weakly sclerotized, densely covered with microsetae together with six or seven short fine hairs; inner margin slightly sinuous. Genital fork (Fig. 56 H) of inverted-Y form; stem slender and well sclerotized, with widened apex three times as wide as middle of stem; arms of moderate width, each with moderately sclerotized projection directed forwardly from lateral ridge. Paraproct in ventral view (Fig. 56 I) pointed posteromedially, moderately concave anterolaterally, and with strongly sclerotized anteromedial surface bearing few to several sensilla; paraproct in lateral view (Fig. 56 J) somewhat produced ventrally, 0.5 times as long as wide, covered with 21–24 short to medium-long hairs and numerous microsetae on lateral and ventral surfaces. Cercus in lateral view (Fig. 56 J) short, rounded posteriorly, 0.5 times as long as its greatest width, and covered with medium-long and short hairs. Spermatheca (Fig. 56 K) ovoidal, 1.2 times as long as wide, moderately sclerotized except duct and narrow area of juncture with duct unsclerotized, without discernible reticulate surface patterns; minute internal setae present; accessory ducts subequal in thickness to each other and slightly thicker than main duct. Pupa. Body length 2.3 mm. Head. Integument including antennal sheaths yellow and moderately covered with round tubercles (Fig. 57 A); frons with two pairs of unbranched trichomes (anterior trichome medium-long, posterior one long) (Fig. 57 B); face with pair of unbranched medium-long trichomes (Fig. 57 C), which are subequal in length to anterior ones of frontal trichomes. Thorax. Integument yellow, moderately covered with round tubercles except dorsal surface of posterior half covered with cone-shaped tubercles; thorax with two long anterodorsal trichomes (posterior trichome broken, not measureable but probably as long as or slightly shorter than anterior one) (Fig. 57 D), two anterolateral trichomes (anterior trichome medium-long, posterior one long) (Fig. 57 E), one medium-long mediolateral trichome (Fig. 57 F), and three ventrolateral trichomes (one short and two medium-long) (Fig. 57 G), on each side; all trichomes unbranched. Gill (Fig. 57 H) with six slender thread-like filaments in three pairs (one dorsal, one middle and one ventral) arising from short common basal stalk; basal fenestra small; all pairs short-stalked; stalks of dorsal and ventral pairs lying at angle of 90 degrees when viewed laterally; filaments decreasing in length and thickness from dorsal to ventral, with longest filament 1.3 mm long and shortest filament 0.8 mm long; dorsal filament of dorsal pair thickest, and two filaments of ventral pair thinnest; relative thickness of each filament from dorsal to ventral when measured basally 1.0:1.0:0.8:0.8:0.7:0.7; all filaments light brown, tapered toward apex, with moderately developed annular ridges and furrows forming definite reticulate surface patterns except apical half of dorsal pair of filaments and middle and ventral pairs of filaments with weakly or indistinct ridges and furrows, and densely covered with minute tubercles. Abdomen. Dorsally, all segments unpigmented; segment 1 with one unbranched medium-long seta (Fig. 57 I) on each side; segment 2 with one unbranched short seta and five minute setae (Fig. 57 J) on each side; segments 3 and 4 each with four distinct hooked spines and one unbranched spinous short seta on each side; segments 5–7 lacking spinecombs; segments 6 with comb-like groups of minute spines on each side; segments 8 and 9 each with distinct spine-combs in transverse row and comb-like groups of minute spines on each side; segment 9 without terminal hooks. Ventrally, segments 4–8 unpigmented and segment 9 somewhat yellowish; segments 3–8 each with comblike groups of minute spines; segment 4 with one unbranched or bifid stout hook and few slender minute setae on each side; segment 5 with pair of bifid stout hooks submedially and few unbranched short setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer stout hooks somewhat separated from each other, and few unbranched short setae on each side. Grapnel-shaped hooklets absent on each side of segment 9. Cocoon (Fig. 57 K). Wall-pocket-shaped, roughly woven anteriorly with many small open spaces in webs, ochreous, and not extended ventrolaterally; individual threads visible; 2.0 mm long by 1.0 mm wide. Male and mature larva. Unknown. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 40, Holotype, Simulium (S.) fuscicoxae , Female, coll. Vietnam, 24-IV-2014, Takaoka et al.], reared from a pupa collected from a small stream (width 1–2 m, water temperature 16.0˚C, exposed to the sun, elevation 1,492 m, 12˚07’59.430”N/108˚35’42.001”E), slowly flowing in open land, 45 km from Dalat, Da Chais, Lac Duong, Lam Dong Province, southern Vietnam, 24-IV-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau. Biological notes. The pupa of this new species was collected from a slender tree root trailing in the current. Associated species were S. (G.) confertum, S. (S.) chamlongi and S. (S.) nodosum . Distribution. Vietnam (Lam Dong). Etymology. The species name fuscicoxae refers to the dark fore coxae of the female of this new species. Remarks. Simulium (S.) fuscicoxae sp. nov. is assigned to the S. tuberosum species-group of the subgenus Simulium, defined by Rubtsov (1956), based on the unpatterned female scutum, simple claw, paired clustered hairs on the seventh sternite (Fig. 56 F), and ordinary ovipositor valves (Fig. 56 G), pupal gill with six slender filaments (Fig. 57 H) and simple wall-pocket-shaped cocoon (Fig. 57 K). This new species is characterized in the female by a sensory vesicle having a large opening (Fig. 56 A), dark short hairs on the scutum, darkened fore coxae, a pair of clustered stout hairs on the ventral surface of abdominal segment 7 (Fig. 56 F), and in the pupa by lacking spine-combs on the dorsal surface of abdominal segment 7. By having the darkened female fore coxae and pupal abdominal segment 7 lacking spine-combs, this new species is distinguished from seven of eight related species with a pair of clustered stout hairs on female sternite 7: S. (S.) rufibasis Puri and S. (S.) ramosum Puri from India, S. (S.) doipuiense (complex), S. (S.) manooni Takaoka & Choochote, S. (S.) weji Takaoka, all from Thailand, S. (S.) neorufibais Sun, and S. (S.) xinbinen Sun, both from China (Chen and An 2003; Puri 1932a; Takaoka 2001a; Takaoka and Choochote 2005c). The remaining species, S. (S.) setsukoae Takaoka & Choochote, from Thailand, which has the darkened female fore coxae, differs from this new species by having a longer female sensory vesicle (0.4–0.5 times the length of the third maxillary palpal segment) with a moderate-sized opening, and triangular ovipositor valves, each with a pointed posteromedian tip (Takaoka and Choochote 2004a). Simulium (Simulium) rosliramlii Takaoka & Chen sp. nov. Female. Body length 2.5–2.9 mm. Head. Slightly narrower than thorax. Frons black, shiny, with several dark stout hairs along lateral margins; frontal ratio 1.3:1.0:0.9–1.1; frons:head ratio 1.0:3.4–3.8. Fronto-ocular area well developed, short, directed laterally, and rounded apically. Clypeus black, grayish pruinose, shiny, moderately covered with dark-brown medium-long hairs though mediolongitudinal portion of upper half widely bare. Labrum 0.7–0.8 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, dark brown to brownish black (though base of first flagellomere light brown). Maxillary palp with five segments, medium brown except third segment dark brown; proportional lengths of third, fourth, and fifth segments 1.0:1.0–1.1:2.3–2.4; third segment (Fig. 58 A) of moderate size, with medium-sized ellipsoidal sensory vesicle (0.3–0.4 times length of third segment) having medium-sized or large opening. Maxillary lacinia with11–14 inner and 11–17 outer teeth. Mandible with 33–35 inner and 12 or 13 outer teeth. Cibarium (Fig. 58 B) with 98–110 minute processes, of which several are vestigial, near posterodorsal margin. Thorax. Scutum black, shiny, white pruinose when illuminated at certain angles, moderately covered with yellow short fine hairs interspersed with several dark-brown long upright hairs on prescutellar area. Scutellum dark brown, covered with dark-brown upright long and short hairs. Postnotum black, shiny and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, shiny and white pruinose when illuminated at certain angles, and bare. Legs. Foreleg: coxa yellow; trochanter medium brown with base yellow; femur medium brown with apical cap dark brown; tibia whitish except apical cap dark brown and base light brown, with median outer surface widely white and with bright white sheen when illuminated at certain angles; tarsus black, with moderate dorsal hair crest; basitarsus moderately dilated, 6.4–7.2 times as long as its greatest width. Midleg: coxa brownish black; trochanter medium to dark brown; femur dark brown except apical cap brownish black; tibia dark brown except basal twofifths whitish and apical cap brownish black, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus light to medium brown except basal half of basitarsus whitish yellow. Hind leg: coxa dark brown; trochanter dark yellow to light brown; femur dark brown except base dark yellow to light brown; tibia (Fig. 58 C) medium to dark brown except basal half or little more or less yellowish white, and apical cap brownish black, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus medium brown except little less than basal two-thirds of basitarsus (though base light brown) and basal half of second tarsomere yellowish white; basitarsus (Fig. 58 D) nearly parallel-sided, 6.3–6.9 times as long as wide, and 0.7–0.8 and 0.7 times as wide as greatest widths of hind tibia and femur, respectiv

Genus Simulium Latreille The family Simuliidae is classified in 26 genera, of which Simulium is the largest and most widely distributed genus, with 37 subgenera (Adler and Crosskey 2016). Simulium is the only genus recognized in the Oriental Region, where a total of 524 species are recorded (Adler and Crosskey 2016), and they are further classified in 10 subgenera, i.e., three endemic subgenera (Asiosimulium Takaoka & Choochote, Daviesellum Takaoka & Adler, and Wallacellum Takaoka), one semi-endemic subgenus (Gomphostilbia), four cosmopolitan subgenera (Byssodon Enderlein, Eusimulium Roubaud, Nevermannia and Simulium), and two subgenera with a Palaearctic distribution (Montisimulium and Wilhelmia Enderlein). In the Oriental Region, the subgenus Simulium is dominant, having 232 species (44.3%), followed by Gomphostilbia with 193 component species (36.8%) and Nevermannia with 55 species (10.5%), while seven other subgenera consist of 1 to 16 species. Four subgenera (Gomphostilbia, Montisimulium, Nevermannia and Simulium) have been reported in Vietnam. Definitions of the genus Simulium and 10 subgenera follow those given by Crosskey (1969), Takaoka (2003, 2012), Takaoka and Adler (1997) and Takaoka and Choochote (2005b). The keys to all these subgenera of the genus Simulium are herein updated. The subgenera and species-groups known from Vietnam are shown in bold face type., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 10-11, DOI: 10.5281/zenodo.571608, {"references":["Adler, P. H. & Crosskey, R. W. (2016) World Blackflies (Diptera: Simuliidae): A Comprehensive Revision of the Taxonomic and Geographical Inventory [2016]. 126 pp. Available from: https: // www. clemson. edu / cafls / biomia / pdfs / blackflyinventory. pdf (accessed 10 May 2016)","Crosskey, R. W. (1969) A Re-classification of the Simuliidae (Diptera) in Africa and Its Islands. In: Bulletin of the British Museum Natural History. Entomology. Supplement 14. United States Department of Agriculture, London, pp. 1 - 194 pp.","Takaoka, H. & Adler, P. H. (1997) A new subgenus, Simulium (Daviesellum), and a new species, S. (D.) courtneyi, (Diptera: Simuliidae) from Thailand and Peninsular Malaysia. Japanese Journal of Tropical Medicine and Hygiene, 25 (1), 17 - 27. https: // doi. org / 10.2149 / tmh 1973.25.17","Takaoka, H. & Choochote, W. (2005 b) A new subgenus and a new species of Simulium s. l. (Diptera: Simuliidae) from Thailand. Medical Entomology and Zoology, 56, 33 - 41."]}

Simulium (Gomphostilbia) montiblense Takaoka, 1983 Simulium (Gomphostilbia) montiblense Takaoka, 1983: 71 ���73 (Female, male, pupa and larva). Distribution. Philippines (Palawan) and Vietnam. Remarks. This species was described from Palawan, the Philippines by Takaoka (1983), and later recorded from Vietnam by Crosskey and Howard (1997). No detailed information of this record was available; hence, the material and locality in Vietnam are unknown. If its identification was based only on the pupal stage, there is a possibility that the species recorded as S. (G.) montiblense is one of three species, i.e., S. (G.) eshimai sp. nov., S. (G.) longlanhense or S. (G.) parahiyangum because the pupal gills of S. (G.) montiblense and the three other species are all short, and their arrangements are almost indistinguishable from one another (Takaoka 1983; Takaoka and Sigit 1992; Takaoka et al. 2015a)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 60, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. (1983) The Blackflies (Diptera: Simuliidae) of the Philippines. Japan Society For The Promotion of Science, Tokyo, xi + 199 pp.","Crosskey, R. W. & Howard, T. H. (1997) A New Taxonomic and Geographical Inventory of World Black Flies (Diptera: Simuliidae). Natural History Museum, London, 144 pp.","Takaoka, H. & Sigit, S. H. (1992) A new blackfly species of Simulium (Gomphostilbia) from Java, Indonesia (Diptera: Simuliidae). Japanese Journal of Tropical Medicine and Hygiene, 20 (2), 135 - 142. https: // doi. org / 10.2149 / tmh 1973.24.163","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

Simulium (Simulium) sansahoense Takaoka & Chen sp. nov. Female. Body length 2.5 ��� 2.6 mm. Head. Slightly narrower than thorax. Frons black, shiny, with bluish reflection when illuminated at certain angles, with several dark stout hairs along lateral margins and few to several yellow fine hairs near antennal bases; frontal ratio 1.3:1.0:0.9���1.1; frons:head ratio 1.0:3.3���3.5. Fronto-ocular area well developed, short, directed laterally, and rounded or pointed apically. Clypeus black, shiny and white pruinose when illuminated at certain angles, moderately covered with dark-brown medium-long hairs mixed with yellow fine hairs (though mediolongitudinal portion somewhat widely bare on upper half to three-fifths). Labrum 0.6 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, dark brown, except scape, pedicel and first flagellomere yellow when viewed ventrally, but dark brown except scape, pedicel and basal one-third of first flagellomere yellow when viewed dorsally. Maxillary palp with five segments, medium brown except third segment dark brown; proportional lengths of third, fourth, and fifth segments 1.0:1.2:2.7; third segment (Fig. 34 A) of moderate size, with medium-sized ellipsoidal sensory vesicle (0.3 ��� 0.4 times length of third segment) having medium-sized opening. Maxillary lacinia with 11 or 12 inner and 13 ��� 15 outer teeth. Mandible with 29 inner and 12 outer teeth. Cibarium (Fig. 34 B) with 30 or 31 minute processes near posterodorsal margin. Thorax. Scutum black, shiny and white pruinose with three faint dark vittae (one median, two submedian) when illuminated at certain angles, moderately covered with yellow short fine hairs interspersed with several dark-brown long upright hairs on prescutellar area. Scutellum brownish black, covered with dark-brown upright long and yellow short hairs. Postnotum brownish black, shiny and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, shiny and white pruinose when illuminated at certain angles, and bare. Legs. Foreleg: coxa and trochanter whitish yellow; femur yellow with apical cap light brown; tibia whitish yellow except apical cap dark brown, with median outer surface widely white and with bright white sheen when illuminated at certain angles; tarsus black, with moderate dorsal hair crest; basitarsus greatly dilated, 5.8 ��� 5.9 times as long as its greatest width. Midleg: coxa dark brown; trochanter whitish yellow with apical portion partially light brown; femur yellow except apical cap light brown; tibia whitish yellow except apical tip light brown, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus medium brown except basal four-fifths of basitarsus whitish yellow. Hind leg: coxa medium to dark brown; trochanter yellowish white; femur yellow except apical cap light brown; tibia white on posterior surface of basal half and yellow on rest except apical cap medium brown, and with whitish sheen widely on posterior surface when illuminated at certain angles; tarsus medium brown except little more than basal two-thirds of basitarsus (though base light brown) and basal half of second tarsomere yellowish white; basitarsus (Fig. 34 C) nearly parallel-sided, 6.2 ��� 6.3 times as long as wide, and 0.8 and 0.7 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 34 C) moderately developed, nearly as long as wide, and 0.4 times as wide as greatest width of basitarsus; pedisulcus (Fig. 34 C) well developed; claw (Fig. 34 D) with small subbasal tooth. Wing. Length 2.5 ��� 2.7 mm. Costa with dark spinules and hairs; subcosta haired except apical one-fifth to half bare; basal section of radial vein bare; R1 with dark-brown spinules and hairs; R2 with dark-brown hairs; hair tuft on base of radius dark brown; basal cell absent. Halter. White except base darkened. Abdomen. Basal scale dark brown, with fringe of yellow hairs. Dorsal surface of abdomen medium brown to brownish black, with dark short hairs; tergite 2 shiny and silvery iridescent when illuminated at certain angles and tergites 6���9 shiny when illuminated at certain angles. Ventral surface light to medium brown; segment 7 without sternal plate. Terminalia. Sternite 8 (Fig. 34 E) well sclerotized and bare medially, covered with 6���10 long and medium-long stout hairs and three or four short fine hairs on each side. Ovipositor valves (Fig. 34 E) nearly tongue-like, rounded posteromedially, membranous, each densely covered with microsetae together with five to eight short to medium-long hairs; inner margin deeply concave medially. Genital fork (Fig. 34 F) of inverted-Y form; stem slender and well sclerotized; arms of moderate width, each with strongly sclerotized apical portion having distinct projection directed anterodorsally. Paraproct in ventral view (Fig. 34 G) nearly quadrate, with anteromedian portion depressed and moderately sclerotized having eight or nine sensilla on its surface; paraproct in lateral view (Fig. 34 H) somewhat produced ventrally, 0.7 times as long as wide, covered with 15���19 short to medium-long hairs and numerous microsetae on lateral and ventral surfaces. Cercus in lateral view (Fig. 34 H) short, rounded posteriorly, 0.56 times as long as its greatest width, and covered with medium-long and short hairs. Spermatheca (Fig. 34 I) ovoidal, 1.2 times as long as wide, sclerotized except duct and narrow area of juncture with duct unsclerotized, without discernible reticulate surface patterns; minute internal setae present; accessory ducts subequal in thickness to each other and slightly thicker than main duct. Male. Body length 2.6���3.0 mm. Head. Slightly wider than thorax. Upper eye medium brown, with large facets in 21 or 22 vertical columns and in 21���23 horizontal rows. Clypeus black, thickly white pruinose, silvery or bluish, shiny when illuminated at certain angles, covered with dark-brown hairs along lateral margins and near ventral margin (medial portion widely bare). Antenna composed of scape, pedicel and nine flagellomeres, medium brown to brownish black except base of first flagellomere dark yellow; first flagellomere elongate, 1.7 times as long as second one. Maxillary palp grayish to dark brown, composed of five segments with proportional lengths of third, fourth, and fifth segments 1.0:1.3:2.9; third segment (Fig. 35 A) of moderate size; sensory vesicle (Fig. 35 A) small, ellipsoidal (0.3 times as long as third segment), and with small opening. Thorax. Scutum black, with white pruinose pattern, i.e., anterior pair of crescent spots on shoulders extending posteriorly along lateral margins connected near base of wings to large transverse posterior spot entirely covering prescutellar area; these pruinose areas silvery or bluish iridescent when illuminated at certain angles; scutum uniformly and moderately covered with yellow recumbent short hairs interspersed with dark-brown long upright hairs on prescutellar area. Scutellum brownish black, with several dark-brown long upright hairs and yellow short hairs. Postnotum black, white pruinose when illuminated at certain angles and bare. Pleural membrane bare. Katepisternum longer than deep, black, white pruinose when illuminated at certain angles, and bare. Legs. Foreleg: coxa whitish yellow; trochanter light brown except base whitish yellow; femur light brown with apical cap medium brown, though inner surface of basal half yellowish; tibia medium brown except median large portion widely white on outer surface, and with bright white sheen widely on outer surface when illuminated at certain angles; tarsus brownish-black to black, with moderate dorsal hair crest; basitarsus greatly dilated, 6.6���6.8 times as long as its greatest width. Midleg: coxa brownish black; trochanter medium brown except base yellowish white; femur light brown with apical cap medium brown; tibia light brown except basal one-third yellow and apical cap medium brown; tibia with white sheen on posterior surface of basal one-third when illuminated at certain angles; tarsus medium to dark brown except basal half or little more of basitarsus whitish yellow. Hind leg: coxa dark brown; trochanter whitish yellow; femur medium brown except base whitish yellow and apical cap dark brown; tibia medium brown except apical cap brownish black and basal tip yellowish white; tarsus (Fig. 35 B) medium to dark brown except basal half or little more of basitarsus whitish yellow (though extreme base darkened) and basal half of second tarsomere yellowish white; basitarsus (Fig. 35 B) much enlarged, gradually widened from base to apical one-third, then slightly narrowed to apex, 4.1���4.9 times as long as its greatest width, and 0.7���0.8 and 0.9 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 35 B) small, slightly shorter than wide, 0.3 times as wide as greatest width of basitarsus; pedisulcus (Fig. 35 B) well developed. Wing. Length 2.6���2.7 mm. Other features as in female except subcosta bare. Halter. White except basal portion darkened. Abdomen. Basal scale brownish black, with fringe of dark long hairs. Dorsal surface of abdomen dark brown to brownish black, with dark short hairs; segments 2, 5, 6 and 7 each with pair of silvery or bluish iridescent spots dorsolaterally, those on segment 2 broadly connected in middle to each other. Genitalia. Coxites, styles and ventral plate in ventral view as in Fig. 35 C. Coxite in ventrolateral view (Fig. 35 D) 0.8 times as long as wide. Style in ventrolateral view (Fig. 35 E) elongate, 2.9 times as long as its greatest width near base, nearly parallel-sided from base to little more than basal one-third, then tapered toward middle, and nearly parallel-sided or slightly widened to apex, and with distinct apical spine; style in medial view (Fig. 35 F) 1.4 times as long as coxite, widened from base to basal one-fourth, tapered to little less than apical one-third, then nearly parallel-sided to apex. Ventral plate in ventral view (Fig. 35 C) well sclerotized, with narrow body having ventrally produced process posteriorly, which bears toothed posterolateral margins and is covered with many minute setae on anterolateral surface; arms divergent outward, then convergent apically; ventral plate in lateral view (Fig. 35 G) with posterior margin serrated from base to apical tip and with anterolateral surfaces covered with many microsetae; ventral plate in end view (Fig. 35 H) elliptical, with both lateral margins gently rounded, and each with several teeth. Median sclerite in lateral view (Fig. 35 G) arising from anterior margin of body of ventral plate, directed dorsally; median sclerite in caudal view (Fig. 35 I) plate-like, nearly parallel-sided to apex, with round apex, brown basally, but not so well sclerotized apically. Paramere in caudal view (Fig. 35 J) with enlarged basal portion and with several distinct hooks and several smaller ones. Aedeagal membrane densely covered with minute setae, and with moderately sclerotized dorsal plate in form of horizontal bar (Fig. 35 K). Abdominal segment 10 (Fig. 35 L, M) with three or five hairs on ventral surface and three to five hairs on lateral surface on each side. Cercus (Fig. 35 L, M) small, rounded, with 10 or 11 distinct hairs. Pupa. Body length 3.0��� 3.2 mm. Head. Integument ochreous except ventral and lateral surfaces whitish yellow and antennal sheaths yellow, densely covered with small round tubercles; frons with two pairs of unbranched short slender trichomes (Fig. 36 A), arising close together; face with pair of unbranched medium-long somewhat stout trichomes (Fig. 36 B). Thorax. Integument light brown except wing sheaths yellow, moderately covered with small round tubercles; thorax with three medium-long stout anterodorsal trichomes (one posterior trichome somewhat narrower than two anterior ones) (Fig. 36 C), two medium-long stout anterolateral trichomes (anterior trichome shorter and more slender than posterior one) (Fig. 36 D), one medium-long stout mediolateral trichome (Fig. 36 E), and three ventrolateral trichomes (one anterior trichome short and slender, two other trichomes medium-long and stout) (Fig. 36 F), on each side; all unbranched. Gill (Fig. 36 G) with eight slender thread-like filaments arranged as (2+2)+(2+2) from dorsal to ventral, arising from short common basal stalk; all pairs short-stalked except second pair from above almost sessile; length of filaments variable: upper filaments of first and second pairs from above shortest (0.84 mm long), two filaments of fourth pair from above longest (1.2���1.3 mm long), and other filaments intermediate in length (1.0��� 1.1 mm long); all filaments subequal in thickness to one another, though two filaments of fourth pair slightly thicker than others; all filaments dark brown, slightly tapered toward apices, with annular furrows (annular ridges not well developed), and densely covered with minute tubercles. Abdomen. Dorsally, all segments unpigmented except segments 1 and 2 entirely light brown, and also segment 3 occasionally with wide darkened area anteriorly; segment 1 with one unbranched short hair-like seta (Fig. 36 H) on each side; segment 2 with one unbranched short hair-like seta and five minute setae, of which three or four are stout (Fig. 36 I), on each side; segments 3 and 4 each with four distinct hooks and one unbranched minute seta on each side; segment 5���7 lacking spine-combs; segment 8 with distinct spine-combs in transverse row on each side; segments 6���9 each with comb-like groups of minute spines on each side; segment 9 with pair of small conical terminal hooks (Fig. 36 J). Ventrally, segments 3���8 unpigmented, each with comb-like groups of minute spines; segment 4 with few minute setae on each side; segment 5 with pair of bifid hooks submedially and few minute setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer hooks somewhat separated from each other, and few minute setae on each side. Grapnel-shaped hooklets absent on each side of segment 9. Cocoon (Fig. 36 K, L). Corbicular, moderately woven, ochreous, not extended ventrolaterally, and with several large open spaces anteriorly; individual threads invisible; 3.5���4.2 long by 1.0��� 1.3 mm wide. Mature larva. Body length 5.3���6.0 mm. Body vermilion to ochreous (though intersegmental areas from thoracic segment 3 to abdominal segment 5 paler) except ventral surface of thorax and abdominal segments 1���4 light grayish-green, and that of abdominal segments 5���9 unpigmented. Head. Cephalic apotome (Fig. 37 A) variable in color patterns: e.g., some cephalic apotome whitish yellow to yellow though medial portion narrowly darkened along posterior margin, with faint or moderate positive head spots; some others whitish yellow on anterior three-fifths, with faint anterior spot of mediolongitudinal spots, and light to dark brown on posterior twothirds with faint to moderate negative or obscure spots; some others light to medium brown on anterior one-third, medium to dark brown on posterior two-thirds, with faintly or moderately negative spots, and medial portion between dark areas yellow, with obscure or faintly positive anterior spot of mediolongitudinal spots; some others widely yellowish except narrow area along posterior margin darkened and somewhat light brown medially, with obscure or negative head spots. Lateral surface of head capsule light to medium brown except eye-spot region whitish and anterior portion near anterior margin and area below eye-spot region yellowish to varying extent, with spots near posterior margin obscure or faintly or moderately negative, and isolated spot below eye-spot region often positive; eyebrow distinct. Ventral surface of head capsule (Fig. 37 B) light to medium brown except anterior area near hypostoma and both lateral areas yellowish to varying extent; long spot on each side of postgenal cleft obscure or faintly positive or negative. Head capsule sparsely covered with minute colorless setae. Antenna composed of three articles and apical sensillum, much longer than stem of labral fan; length ratio of three articles (from base to tip) 1.0:1.3 ��� 1.4:0.6. Labral fan with 52���56 primary rays. Mandible (Fig. 37 C) with mandibular serration composed of two teeth (one medium-sized, one small); main tooth at obtuse angle against mandible on apical side; supernumerary serrations absent; comb-teeth decreasing in length from first to third. Hypostoma (Fig. 37 D) with nine anterior teeth, of which median tooth is slightly longer than corner teeth, and intermediate teeth on each side shortest; lateral margins serrate apically; six or seven hypostomal bristles per side lying divergent posteriorly from lateral margin. Postgenal cleft (Fig. 37 B) rounded, 4.0 times length of postgenal bridge; sheath of subesophageal ganglion weakly pigmented. Cervical sclerites on each side composed of one light-brown rod-like piece and one light-brown elliptical piece, not fused to occiput. Thorax and Abdomen. Histoblast of pharate pupal gill with eight short filaments. Thoracic cuticle sparsely covered with minute colorless setae dorsally. Abdominal segments 1 ��� 5 each with pair of small protuberances (Fig. 37 E) dorsally; abdominal cuticle sparsely or moderately covered with minute colorless setae dorsally and dorsolaterally; last abdominal segment moderately covered with short colorless setae on each side of anal sclerite. Rectal scales present. Rectal organ compound, each lobe with 14 ��� 18 finger-like secondary lobules. Anal sclerite X-shaped, with short broad anterior arms 0.7 times length of posterior ones; one to five sensilla on base of anal sclerite; four to six sensilla posterior to posterior arms. Last abdominal segment somewhat swollen laterally but lacking ventral papillae. Posterior circlet with 84 ��� 86 rows of hooklets with up to 16 ��� 19 hooklets per row. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 34, Holotype, Simulium (S.) sansahoense, Female, coll. Vietnam, 20-XII-2014, Takaoka et al.], reared from a pupa collected from a river (width 6.0 m, depth 12 cm, water temperature 10.0˚C, exposed to the sun, elevation 1,194 m, 22˚19���44.349���N/103˚49���49.930���E), moderately flowing from a natural forest, San Sa Ho, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. PARATYPES: Four females, six males (all reared from pupae), two pupae and 10 mature larvae, in 80% ethano,l same data as those of the holotype, labeled in each vial as [UMSRP: Vietnam 0 34, Paratype, Simulium (S.) sansahoense, coll. Vietnam, 20-XII-2014, Takaoka et al.]. Biological notes. The pupae and larvae of this new species were collected from plastic plates in the current. The associated species were S. (S.) daoense sp. nov. and S. (S.) phuluense sp. nov. Distribution. Vietnam (Lao Cai). Etymology. The species name sansahoense refers to the name of the locality, San Sa Ho, where this new species was collected. Remarks. Simulium (S.) sansahoen, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 82-89, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Saito, K. (2007) A species list of black flies (Diptera: Simuliidae) in Japan. Yugaiseibutsu, 4, 44 - 60. [in Japanese]","Takaoka, H. (1976) Studies on blackflies of the Nansei Islands, Japan (Simuliidae; Diptera). II. On six species of the subgenera Gomphostilbia Enderlein, Morops Enderlein, Odagmia Enderlein and Gnus Rubzov, with the description of Simulium (Gomphostilbia) okinawense sp. nov. Japanese Journal of Sanitary Zoology, 27, 385 - 398. https: // doi. org / 10.7601 / mez. 27.385","Xue, H. T. (1992) A new species of blackfly Simulium from Yunnan Province, China (Diptera: Simuliidae). Acta Zootaxonomica Sinica, 17 (2), 93 - 96.","Takaoka, H. (1983) The Blackflies (Diptera: Simuliidae) of the Philippines. Japan Society For The Promotion of Science, Tokyo, xi + 199 pp.","Takaoka, H. & Davies, D. M. (1995) The Black Flies (Diptera: Simuliidae) of West Malaysia. Kyushu University Press, Fukuoka, viii + 175 pp.","Takaoka, H. & Sigit, S. H. (1997) Three new black fly species of Simulium (Diptera: Simuliidae) from Sumatra, Indonesia. Japanese Journal of Tropical Medicine and Hygiene, 25 (2), 69 - 80."]}

Simulium (Gomphostilbia) chaudinhense Takaoka & Sofian-Azirun sp. nov. Female. Nearly as in female of S. (G.) asakoae except following characters. Body length 2.0��� 2.2 mm. Head. Frontal ratio 1.6���1.8:1.0:2.2���2.4; frons:head ratio 1.0:4.0���4.8. Labrum 0.5 times length of clypeus. Maxillary palp: proportional lengths of third, fourth, and fifth segments 1.0:1.2:2.7���2.9; sensory vesicle (Fig. 8 A) small, ellipsoidal (0.2���0.3 times length of third segment), with small opening. Maxillary lacinia with 9���11 inner and 11���15 outer teeth. Mandible with 23 or 24 inner teeth and three or four outer teeth at some distance from tip. Legs. Foreleg: coxa and trochanter yellowish white; femur light brown with apical cap medium brown (though extreme tip yellowish); tibia white except little more than apical one-fourth dark brown, covered with white fine hairs on basal four-fifths; basitarsus moderately dilated, 6.2���6.6 times as long as its greatest width. Midleg: femur light brown with base yellowish white (though inner surface of basal half yellowish white) and apical cap medium brown (though extreme tip yellowish); tibia light brown except basal one-third yellowish white (though inner surface of basal two-thirds yellowish white) and apical cap brownish black, covered with yellowish fine hairs on posterior and inner surfaces of basal two-thirds; tarsus medium to dark brown though basal half or little more of basitarsus yellow. Hind leg: basitarsus 5.7���5.8 times as long as wide, and 0.7 and 0.6���0.7 times as wide as greatest widths of tibia and femur, respectively; calcipala 0.5 times as wide as greatest width of basitarsus; claw with large basal tooth 0.53 times length of claw. Wing. Length 2.0��� 2.2 mm. Abdomen. Basal scale light brown, with fringe of whitishyellow hairs. Terminalia. Sternite 8 bare medially, with 14���22 medium-long to long hairs together with one or two slender short hairs on each side. Ovipositor valves moderately covered with microsetae interspersed with two short hairs; inner margins nearly straight or slightly sinuous, somewhat sclerotized. Paraproct in ventral view with three to six sensilla on anteromedial surface; paraproct in lateral view 0.7 times as long as wide, with 19���32 mediumlong to long hairs on ventral and lateral surfaces. Cercus in lateral view 0.33 times as long as wide. Spermatheca ellipsoidal, 1.5���1.6 times as long as its greatest width. Male. Nearly as in male of S. (G.) asakoae except following characters. Body length 2.0��� 2.5 mm. Head. Upper-eye facets in 10 (rarely 9) vertical columns and 12 horizontal rows. Antenna: first flagellomere 1.8 times length of second one. Maxillary palp: proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.5; sensory vesicle small, ellipsoidal (0.2 times length of third segment), and with small opening. Legs. Foreleg: basitarsus moderately dilated, 7.6���7.9 times as long as its greatest width. Hind leg: basitarsus enlarged, wedge-shaped, 3.4 times as long as wide, and 1.0 and 1.2���1.3 times as wide as greatest width of tibia and femur, respectively; calcipala slightly shorter than basal width, and 0.3 times as wide as greatest width of basitarsus. Wing. Length 2.0��� 2.1 mm. Subcosta bare or with one to five hairs. Genitalia. Coxite in ventral view 1.9 times as long as its greatest width. Style in ventrolateral view slightly tapered toward apex, with truncated apex, 0.8 times length of coxite. Ventral plate in ventral view with body transverse, 0.5 times as long as wide, and posterior margin somewhat concave medially (though posterior margin slightly convex medially when ventral plate is slightly tilted). Cercus small, rounded, with 17 or 18 hairs. Pupa. Body length 2.4���2.5 mm. As in pupa of S. (G.) asakoae except following characters. Thorax. Gill (Fig. 8 B) composed of eight slender thread-like filaments, arranged as [(2+1)+(1+2)]+2 from dorsal to ventral; common basal stalk 0.6���0.7 times length of interspiracular trunk; dorsal and middle triplets sharing short stalk 0.4���0.6 times length of common basal stalk; dorsal triplet composed of one individual filament and two paired filaments with short primary and secondary stalks (primary stalk usually much longer than secondary stalk) or three filaments rarely arising at same level from primary stalk); middle triplet composed of one individual filament and two paired filaments with short primary and secondary stalks (primary stalk usually much longer than secondary stalk, though primary stalk slightly shorter than secondary stalk in one pupa); ventral paired filaments with medium-long stalk 1.1���1.5 times length of common basal stalk; primary stalk of dorsal triplet lying against that of lower pair at angle of 75���90 degrees when viewed laterally; three filaments of dorsal triplet subequal in length (2.0��� 2.5 mm long including their own stalks and common basal stalk) and thickness to one another; three filaments of middle triplet subequal in length (2.7���2.9 mm) and thickness; two filaments of ventral pair subequal in length (3.0��� 3.1 mm) and thickness to each other. Abdomen. Dorsally, segments 1 and 2 sparsely covered with minute tubercles (Fig. 8 C); segment 5 bare (though one spine-comb on each side in two pupae); segment 9 with pair of flat triangular terminal hooks (Fig. 8 D), of which outer margin 2.4���2.9 times length of inner margin and crenulated. Last segment with three grapnel-shaped hooklets on each side. Cocoon. 3.3���4.0 mm long by 2.2���3.0 mm wide. Mature larva. Body length 4.6���5.1 mm. Body whitish with following grayish and ochreous markings. Grayish markings as in Fig. 8 E: thoracic segment 1 encircled with grayish band (though disconnected ventromedially) narrowly along anterior margin and grayish area on anterior surface of proleg, thoracic segment 2 grayish ventrally and faintly grayish dorsally; all these grayish markings on thorax faded out in some larvae; abdominal segments 1 and 2 each always encircled with dark gray band; abdominal segment 3 rarely grayish ventrally; abdominal segment 4 encircled with light grayish band, though often faded dorsally; abdominal segment 5 encircled with light grayish band, though often faded ventrally or dorsally or entirely; abdominal segment 6 rarely with gray areas laterally and ventrolaterally; abdominal segment 7 rarely with gray areas laterally and ventrally. Ochreous markings as in Fig. 8 F: thoracic segment 1 encircled with ochreous band; thoracic segments 2 and 3 faintly light ochreous dorsally and ventrally; abdominal segment 3 rarely light ochreous dorsally, abdominal segments 4���9 each with distinct ochreous transverse band dorsally, of which those on segments 4���6 often extended laterally and even ventrolaterally, and those of segments 6���8 usually fused to each other laterally, and abdominal segment 7 often with ochreous transverse band ventrally. Head. Head capsule whitish yellow to yellow except dorsomedial area along posterior margin sometimes darkened, eyes-pot region whitish, and lateral area along posterior margin often darkened widely so that two large dark spots and two small dark spots in front of posterior margin appearing to be obscure (Fig. 8 G), sparsely covered with minute setae (though moderately on dorsal surface); head spots distinctively positive though anterior spots of posterolateral spots usually faint or indistinct; eyebrow not darkened, with small round dark spot above it (Fig. 8 G). Antenna composed of three articles and apical sensillum, longer than stem of labral fan; proportional lengths of first, second, and third articles 1.0:0.7:0.8��� 0.9. Labral fan with 38���42 primary rays. Mandible (Fig. 8 H) with three comb-teeth decreasing in length from first tooth to third; mandibular serration composed of two teeth (one medium-sized, one small); major tooth at angle of little less than 90 degree against mandible on apical side; supernumerary serrations absent. Hypostoma (Fig. 8 I) with row of nine apical teeth, of which median tooth is longer than each corner tooth; lateral margin smooth; four or five hypostomal bristles per side lying nearly parallel to lateral margin. Postgenal cleft (Fig. 8 J) arrow-headshaped (though not pointed apically), medium-long, 2.1���2.6 times length of postgenal bridge. Cervical sclerites composed of pair of small yellow rod-like pieces. Thorax and Abdomen. Thoracic proleg without hairs; thoracic cuticle and abdominal cuticle of segments 1 and 2 almost bare; abdominal cuticle of segments 3 and 4 sparsely covered with minute seate dorsally, that of segments 5���9 moderately covered with slightly darkened unbranched minute setae mixed with unpigmented shorter minute setae (Fig. 8 K) on dorsal and dorsolateral surfaces; last abdominal segment densely covered with unbranched colorless minute setae on dorsolateral and lateral surfaces of each side of anal sclerite and on each lateral surface even down to base of ventral papilla; thorax and abdomen without dorsal protuberances. Rectal scales absent. Rectal organ compound, each of three lobes with 8���11 finger-like secondary lobules. Anal sclerite of usual X-form, with anterior arms 1.1 times as long as posterior ones, broadly sclerotized at base; no sensilla on broad base and posterior to posterior arms; accessory sclerite absent. Last abdominal segment with pair of large conical ventral papillae. Posterior circlet with 74 or 75 rows of hooklets with up to 13 or 14 hooklets per row. Type material. HOLOTYPE: Male (with its associated pupal exuviae and cocoon) in 80% ethanol) labeled in a vial as [UMSRP: Vietnam 0 24, Holotype, Simulium (G.) chaudinhense, Male, coll. Vietnam, 11-XII-2015, Takaoka et al.], reared from a pupa collected from a slow-flowing stream (width 1.0 m, depth 5���10 cm, bottom sandy, water temperature 18.0˚C, shaded, elevation 80 m, 19˚30���46.589���N/105˚09���10.470���E), Chau Dinh, Quy Chau, Nghe An Province, northern Vietnam, 11-XII-2015, by H. Takaoka, M. Sofian-Azirun, C.D. Chen & K.W. Lau. PARATYPES: Six females, two males and three mature larvae, labeled in vials as [UMSRP: Vietnam 0 24, Paratype, Simulium (G.) chaudinhense, coll. Vietnam, 11-XII-2015, Takaoka et al.], same data as those of holotype. Ecological notes. The pupae and larvae of this new species were attached to grass leaves trailing in the current. Associated species were S. (G.) parahiyangum and S. (G.) unii sp. nov. Distribution. Vietnam (Nghe An). Etymology. The species name chaudinhense refers to the locality name, Chau Dinh, where this new species was collected. Remarks. This new species is similar to S. (G.) asakoae but is distinguished in the female by the shorter sensory vesicle (Fig. 8 A) and longer claw tooth, in the male by the smaller number of upper-eye facets, in the pupa by the presence of minute tubercles on abdominal segments 1 and 2 (Fig. 8 C), and in the larva by abdominal segments 1 and 2 each encircled with a grayish band (Fig. 8 E)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 23-26, DOI: 10.5281/zenodo.571608

Simulium (Simulium) xuandai Takaoka, Sofian-Azirun & Ya���cob, 2014 Simulium (Simulium) xuandai Takaoka, Sofian-Azirun & Ya���cob (in Takaoka et al., 2014a): 361���364 (Male and pupa). Distribution. Vietnam (Vinh Phuc). Remarks. This species was described from a male reared from a pupa collected from Tam Dao, Vinh Phuc Province, northern Vietnam (Takaoka et al. 2014a). The female and larva remain to be collected., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 125, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 a) New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam. Zootaxa, 3838 (3), 347 - 366. https: // doi. org / 10.11646 / zootaxa. 3838.3.6"]}

Simulium (Gomphostilbia) inthanonense Takaoka & Suzuki, 1984 Simulium (Gomphostilbia) inthanonense Takaoka & Suzuki, 1984: 18 ���21 (Female, male, pupa and larva). Distribution. South China, Thailand and Vietnam (Bac Thai and Ha Thai). Remarks. This species was originally described from Thailand by Takaoka and Suzuki (1984), and later recorded from Vietnam by Pham (1998, 1999). There remains a possibility that the species recorded as S. (G.) inthanonense is either S. (G.) phulocense or S. (G.) unii sp. nov. or another related species, as its identification was based on only two pupae and three larvae. These three species and a few other related species have the same shape of the cocoon with a short anterodorsal projection, as shown in Fig. 19 E., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 53, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Suzuki, H. (1984) The blackflies (Diptera: Simuliidae) from Thailand. Japanese Journal of Sanitary Zoology, 35 (1), 7 - 45.","Pham, X. D. (1998) New records of six black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 49 (2), 121 - 123.","Pham, X. D. (1999) Additional records of three black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 50 (4), 335 - 336."]}

Simulium (Nevermannia) maeaiense Takaoka & Srisuka, 2011 Simulium (Nevermannia) maeaiense Takaoka & Srisuka, 2011: 57 –70 (Female, male, pupa and larva). Specimens examined. One female and one male, reared from pupae collected from a small stream (width 20 cm, depth 2 cm, bottom rocky, water temperature 7.0˚C, partially shaded, elevation 1,893 m, 22˚21’28.378”N/ 103˚45’52.084”E) slowly flowing in shrubs, Lai Chau, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau. Distribution. Thailand and Vietnam (Lao Cai) (New record). Remarks. Simulium (N.) maeaiense was described from Thailand (Takaoka and Srisuka 2011). This is the first record of this species from Vietnam. This species is characterized by the female genital fork with a sclerotized horizontal bar at the base of the anterodorsal projection on each lateral arm, male upper-eye facets in 19 vertical columns and 20 horizontal rows, paramere with five or six hooks, pupal gill with six long filaments arranged horizontally as 2+1+2+1 from inside to outside, and cocoon with an elongate anterodorsal projection (Takaoka and Srisuka 2011). There are differences in several morphological features between Vietnamese and Thai specimens (characters of Thai specimens in parentheses): in the female, body length 3.2 mm (2.4–2.6 mm), wing length 3.1 mm (2.6–2.8 mm), cibarium with 33 processes (40–44 processes), fore basitarsus 8.5 times as long as its greatest width (8.4 times), hind basitarsus 7.6 times as long as its width (6.2–6.8 times), 0.7 times as wide as the hind tibia (0.8 times), 0.6 times as wide as the hind femur (0.6–0.7 times), claw with a large basal tooth 0.46 times as long as the claw (0.49 times), spermatheca ovoidal and 1.3 times as long as its width (1.2 times); in the male, body length 3.0 mm (2.6–2.9 mm), wing length 2.9 mm (2.4–2.5 mm), scutum brownish black to black with no longitudinal vittae (dark brown with three longitudinal vittae), subcosta with three to five hairs (without hairs), hind basitarsus 4.4 times as long as wide (4.6–4.9 times), 1.0 times as wide as the hind tibia (0.9 times), 1.1 times as wide as the hind femur (0.9 times).

Simulium (Simulium) nigrogilvum Summers, 1911 Simulium nigrogilvum Summers, 1911: 586 ���588 (Female). Simulium (Himalayum) nigrogilvum: Takaoka & Suzuki, 1984: 22 ���27 (Female, male, pupa and larva). Simulium (Simulium) nigrogilvum: Otsuka et al., 2003: 113 ���120. Distribution. Thailand and Vietnam. Remarks. This species was assigned to the subgenus Himalayum Lewis (Takaoka and Suzuki 1984) but later transferred to the subgenus Simulium (Otsuka et al. 2003). The females of this species are known to be anthropophilic (Choochote et al. 2005) and to transmit an unknown filarial parasite in Thailand (Fukuda et al. 2003). This species was recorded from Vietnam by Crosskey and Howard (1997). However, data including the material collected and its locality were not given. Simulium (Simulium) turgidum Takaoka & Pham sp. nov. Female. Body length 3.3 mm. Head. Nearly as in female of S. (S.) laocaiense sp. nov. except following characters: Frontal ratio 1.2:1.0:1.0, frons:head ratio 1.0:4.3. Labrum 0.7 times length of clypeus. Antenna: first flagellomere 1.36 times length of second one. Maxillary palp: proportional lengths of third, fourth, and fifth segments 1.0:1.3:3.4; third segment (Fig. 41 A) with apex somewhat produced medially, with medium-sized ellipsoidal sensory vesicle (0.4 times length of third segment) having large or medium-sized opening. Maxillary lacinia with12���13 inner and 13 or 14 outer teeth. Mandible with 25 inner and 12 or 13 outer teeth. Cibarium (Fig. 41 B) with 38 minute processes near posterodorsal margin. Thorax, Legs, Wing and Halter. As in female of S. (S.) laocaiense sp. nov. except following characters: Scutum covered with yellow short hairs. Fore tibia whitish yellow except apical one-fifth brownish black, and little more than apical two-fifths of inner surface light brown to brownish black. Fore basitarsus greatly dilated, 5.8 times as long as its greatest width. Mid tarsus light to medium brown except basal one-third to one-half of basitarsus yellow (though its border not well defined). Hind basitarsus (Fig. 41 C) gradually widened toward apical one-third, then slightly narrowed toward apex, 5.6 times as long as wide, and 0.8 and 0.7 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 41 C) moderately developed, 0.7 times as long as wide, and 0.5 times as wide as greatest width of basitarsus; pedisulcus (Fig. 41 C) well developed. Wing length 3.1 mm. Subcosta haired except near apex bare. Abdomen. Basal scale medium brown to brownish black, with fringe of yellowish hairs. Dorsal surface of abdomen medium brown to black; tergite 2 shiny and white pruinose when illuminated at certain angles and tergites 6���9 shiny. Ventral surface light brown except basal portion of segment 2 white; sternal plate on segment 7 indistinct. Terminalia. Sternite 8 (Fig. 41 D) with 11 or 12 dark-brown medium-long to long stout hairs and three to six yellow short hairs on each lateral surface. Ovipositor valve (Fig. 41 D) wide, somewhat thick except narrow areas along inner and posterior margins thin and transparent, somewhat rounded ventrally, densely covered with microsetae (except narrow transparent portions along inner and posterior margins bare) interspersed with 22���25 yellow short hairs; inner margins somewhat separated from each other. Genital fork (Fig. 41 E, F) of inverted-Y form, with narrow well sclerotized stem; arms of moderate width, each with heavily sclerotized lateral portion, with short projection directed anterodorsally. Paraproct in ventral view (Fig. 41 G) nearly quadrate, 1.2 times as long as its width, with 23 or 24 short to medium-long hairs on lateral and ventral surfaces; anterior surface strongly sclerotized and pigmented, and with four or five short sensilla; paraproct in lateral view (Fig. 41 H) 0.7 times as long as wide, and protruding ventrally beyond ventral margin of cercus. Cercus in lateral view (Fig. 41 H) short, rectangular, 0.6 times as long as wide, with numerous short to medium-long hairs. Spermatheca (Fig. 41 I) globular, 1.1 times as long as greatest width, well sclerotized except small portion of junction with duct unsclerotized, with faintly defined reticulate surface patterns; internal setae present; accessory ducts subequal in thickness to each other, and slightly thicker than major duct. Male. Unknown. Pupa. Body length (excluding gill filaments) 4.0 mm. Head. Integument dark brown except ventral surface ochreous, and bare, without tubercles (though surface appearing to have micro-sculptures formed by numerous fine ridges); frons with two bifid medium-long trichomes (Fig. 42 A); face with one bifid or trifid medium-long trichome on each side (Fig. 42 B). Thorax. Integument dark brown except wing sheaths ochreous, and bare except dorsal surface of posterior half sparsely to moderately covered with round tubercles and basal portions of gills densely covered with tubercles having minute secondary projections (though bare surface appearing to have microsculptures formed by numerous fine ridges); thorax with three long anterodorsal trichomes with four to six branches (Fig. 42 C), two long or medium-long anterolateral trichomes with four branches (anterior one little shorter than posterior one) (Fig. 42 D), one unbranched or bifid medium-long mediolateral trichome (Fig. 42 E), and three ventrolateral trichomes (two unbranched medium-long, one bifid in left side (Fig. 42 F); one unbranched medium-long, one quadrifid medium-long, and one unbranched short (Fig. 42 G) in right side), on each side. Gill (Fig. 42 H) with six somewhat inflated filaments in pairs; common basal stalk short, with small basal fenestra ventrally; all pairs almost sessile; outer filament of dorsal pair longest (1.8 mm long), followed by inner filament of dorsal pair and outer filament of middle pair (1.4 mm long), inner filament of middle pair and outer filament of ventral pair (1.1 mm long), and inner filament of ventral pair (1.0 mm long); each filament widened from base to basal one-fifth to one-third, then tapered toward apex; relative thickness of six filaments from dorsal to ventral when widest portion compared 1.0:0.9:0.9:0.8:0.7:0.6; all filaments dark brown, gradually tapered toward apex; outer filament of dorsal pair and inner filament of ventral pair divergent basally at angle of 60 degrees; cuticular surface with well-defined annular ridges and furrows throughout their length forming definite reticulate surface patterns, covered with minute tubercles. Abdomen. Dorsally, entire surface of segment 1 and anterior half of segment 2 light brown, other segments unpigmented; segment 1 sparsely covered with minute spines laterally, with one unbranched slender medium-long seta (Fig. 42 I) on each side; segment 2 covered with comb-like groups of minute spines submedially, with one unbranched slender short seta and five unbranched minute setae, of which four are stout (Fig. 42 J), on each side; segments 3 and 4 each with four unbranched hooked spines and one unbranched minute seta on each side; segments 7 and 8 each with spine-combs in transverse row on each side; segments 6���9 each with comb-like groups of minute spines; segment 9 without terminal hooks. Ventrally, all segments unpigmented; segment 4 with one unbranched hook and few short setae on each side; segment 5 with pair of unbranched or bifid hooks submedially and few unbranched short seta on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer hooks widely spaced and few unbranched short seta on each side; segments 3���8 each with comb-like groups of minute spines. Grapnel-like hooklets absent. Cocoon (Fig. 42 K, L). Wall-pocket-shaped, thickly woven, with anterolateral windows, ochreous, not extended ventrolaterally; individual threads invisible; 4.0��� 4.2 mm long by 1.6���1.8 mm wide. Mature larva. Body length 6.7���7.5 mm. Body ochreous or partially reddish brown, mottled to varying extent with grayish-black to black pigment except ventral surface of abdominal segments 3���9 unpigmented. Head. Cephalic apotome (Fig. 43 A) whitish yellow on little more than anterior half and light to medium brown on rest (though small medial area in front of posterior margin dark brown); posterior spot of mediolongitudinal spots and posterior half of each mediolateral spot dark brown, anterior spot of mediolongitudinal spots light brown, and other spots indistinct, merged into dark background, or anterior spot of posterolateral spots on each side faintly negative. Lateral surface of head capsule light to medium brown except eye-spot region, eyebrow and median small area along anterior margin yellowish white, with faint or distinct negative spots except one small spot below eye-spot region light brown. Ventral surface of head capsule (Fig. 43 B) light to medium brown except postgenal bridge lighter medially, and elongate spot on each side of cleft indistinct, merged into dark background. Antenna (Fig. 43 C) composed of three articles and apical sensillum, slightly longer than stem of labral fan; antenna yellowish white except third segment dark brown; length ratio of articles (from base to tip) 1.0:1.2���1.3:0.5. Labral fan with 49���51 primary rays. Mandible (Fig. 43 D) with mandibular serration composed of two teeth (one medium-sized and one small); major tooth at obtuse angle apically against mandible; comb-teeth decreasing in length from first to third; supernumerary serrations absent. Hypostoma (Fig. 43 E) with nine anterior teeth, of which median tooth slightly longer than each corner tooth; lateral margins weakly serrate apically; seven or eight hypostomal bristles divergent posteriorly from lateral border on each side. Postgenal cleft (Fig. 43 B) medium-long, triangular, 1.4 times length of postgenal bridge; sheath of subesophageal ganglion well pigmented, wine-glass-shaped. Cervical sclerites on each side composed of one light-brown elliptical piece, not fused to occiput. Thorax and Abdomen. Thoracic and abdominal cuticle bare except last segment of abdomen moderately covered with short colorless setae on each side of anal sclerite. Rectal scales present. Rectal organ compound, each of three lobes with 23���25 fingerlike secondary lobules. Anal sclerite X-shaped, with broadened anterior arms 0.7���0.9 times length of posterior ones; no sensilla on base of anal sclerite and 12 sensilla posterior to posterior arms. Last abdominal segment bulged laterally but lacking ventral papillae. Posterior circlet with 104���110 rows of hooklets with up to 17 or 18 hooklets per row. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 36, Holotype, Simulium (S.) turgidum , Female, coll. Vietnam, 20-XII-2014, Takaoka et al.], reared from a pupa collected from a stream (width 0.5���2.5 m, bottom rocky, water temperature 10.0˚C, exposed to the sun, elevation 1,812 m, 22˚21���27.450���N/103˚46���35.743���E) moderately flowing in a forest, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. PARATYPES: One pupa in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 36, Paratype, Simulium (S.) turgidum, Pupa, coll. Vietnam, 20-XII-2014, Takaoka et al.], collected from a stream (width 0.5 m, bottom rocky, water temperature 11.0˚C, exposed to the sun, elevation 1,750 m, 22˚21���43.110���N/ 103˚47���19.221���E) moderately flowing in a secondary forest, Sapa, Lao Cai Province, northern Vietnam, 20-XII- 2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau; one mature larva, same data as those of the holotype. Biological notes. The pupae of S. (S.) turgidum were collected from trailing grasses. Associated species were S. (M.) nigrofilum sp. nov., S. (N.) laichauense sp. nov., S. (S.) sapaense sp. nov., S. (S.) giayense sp. nov., S. (S.) sp. (S. multistriatum species-group) and S. (S.) sp. (S. variegatum species-group). Distribution. Vietnam (Lao Cai). Etymology. The species name turgidum refers to the inflated gill filaments of this new species. The Latin adjective ���turgidus��� means ���inflated���. Remarks. As for S. (S.) laocaiense sp. nov., S. (S.) turgidum sp. nov. also is placed in the S. griseifrons species-group based on the similarity of the female enlarged ovipositor valve (Fig. 41 D) to that of S. (S.) rudnicki, which is a member of the S. griseifrons species-group. In having inflated pupal gill filaments (Fig. 42 H), this new species is similar to S. (S.) tumidilfilum Luo, Yang & Chen described from Hubei, China (Luo et al. 2010), and S. (S.) waterfallum Zhang, Yang & Chen described from Hainan, China (Zhang et al. 2003), both of which were wrongly placed in the S. multistriatum species-group. However, this new species is distinguished in the female from the latter two species by the ovipositor valve which is triangular with 22���25 short hairs (tongue-like with 5���8 short hairs in S. (S.) tumidilfilum and S. (S.) waterfallum), and in the pupa from S. (S.) tumidilfilum by each inflated filament slightly narrowed at its base (much narrowed in S. (S.) tumidilfilum), and from S. (S.) waterfallum by abdominal segments 7 and 8 each with spine-combs (abdominal segments 6���8 each with spine-combs in S. (S.) waterfallum)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 96-100, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Suzuki, H. (1984) The blackflies (Diptera: Simuliidae) from Thailand. Japanese Journal of Sanitary Zoology, 35 (1), 7 - 45.","Otsuka, Y., Takaoka, H., Aoki, C. & Choochote, W. (2003) Phylogenetic analysis of the subgenus Himalayum within the genus Simulium s. l. (Diptera: Simuliidae) using mitochondrial 16 S rRNA gene sequences. Medical Entomology and Zoology, 54 (1), 113 - 120.","Crosskey, R. W. & Howard, T. H. (1997) A New Taxonomic and Geographical Inventory of World Black Flies (Diptera: Simuliidae). Natural History Museum, London, 144 pp.","Luo, H. B., Yang, M. & Chen, H. B. (2010) A new species of genus Simulium from Xingdou mountain, China (Diptera, Simuliidae). Acta Zootaxonomica Sinica, 35 (3), 472 - 474."]}

Simulium (Gomphostilbia) breviflagellum Takaoka & Sofian-Azirun, 2015 Simulium (Gomphostilbia) breviflagellum Takaoka & Sofian-Azirun (in Takaoka et al., 2015a): 53���57 (Male and pupa) Distribution. Vietnam (Lam Dong). Remarks. This species was described from Lam Dong Province in southern Vietnam by Takaoka et al. (2015a). The female and larva of this species are unknown., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 61, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

Simulium (Gomphostilbia) thuathienense Takaoka & Sofian-Azirun, 2015 Simulium (Gomphostilbia) thuathienense Takaoka & Sofian-Azirun: (in Takaoka et al., 2015a): 48–52 (Female, pupa and larva). Distribution. Vietnam (Thua Thien Hue). Remarks. This species was described from Thua Thien Hue Province in central Vietnam by Takaoka et al. (2015a). The male of this species remains unknown.

Simulium (Gomphostilbia) phulocense Takaoka & Chen, 2015 Simulium (Gomphostilbia) phulocense Takaoka & Chen (inTakaoka et al., 2015a):18–24 (Female, male and pupa). Distribution. Vietnam (Thua Thien Hue). Remark. This species was described from Thua Thien Hue Province in central Vietnam (Takaoka et al. 2015a).

Simulium (Gomphostilbia) duolongum Takaoka & Davies, 1995 Simulium (Gomphostilbia) duolongum Takaoka & Davies, 1995: 19 ���24 (Female, male, pupa and larva). Distribution. Peninsular Malaysia, Sumatra and Vietnam (Bac Thai). Remarks. This species was originally described from Peninsular Malaysia (Takaoka and Davies 1995) and recorded from Vietnam based on two pupae and two larvae by Pham (1999). The identity of the species regarded as S. (G.) duolongum in Vietnam should be confirmed based on the adult males and females., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 52, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Davies, D. M. (1995) The Black Flies (Diptera: Simuliidae) of West Malaysia. Kyushu University Press, Fukuoka, viii + 175 pp.","Pham, X. D. (1999) Additional records of three black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 50 (4), 335 - 336."]}

Simulium (Simulium) malayense Takaoka & Davies, 1995 Simulium (Simulium) malayense Takaoka & Davies, 1995: 120 ���123 (Female, pupa and larva). Distribution. Peninsular Malaysia, Thailand and Vietnam (Bac Thai, Hoa Binh and Ha Tay). Remark. This species was originally described from Peninsular Malaysia by Takaoka and Davies (1995) and later recorded from three provinces in northernVietnam by Pham (1998, 1999)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 117, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Davies, D. M. (1995) The Black Flies (Diptera: Simuliidae) of West Malaysia. Kyushu University Press, Fukuoka, viii + 175 pp.","Pham, X. D. (1998) New records of six black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 49 (2), 121 - 123.","Pham, X. D. (1999) Additional records of three black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 50 (4), 335 - 336."]}

Simulium (Simulium) nakhonense Takaoka & Suzuki, 1984 Simulium (Simulium) nakhonense Takaoka & Suzuki, 1984: 33 ���37 (Female, male, pupa and larva). Distribution. Thailand, China (Hainan) and Vietnam (Bac Giang, Bac Thai, Ha Tay, Lang Son and Yen Bai). Remarks. Simulium (S.) nakhonense was originally described from Thailand (Takaoka and Suzuki 1984). This species was recorded from five provinces in northern Vietnam by Pham (1998, 1999)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 117, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Suzuki, H. (1984) The blackflies (Diptera: Simuliidae) from Thailand. Japanese Journal of Sanitary Zoology, 35 (1), 7 - 45.","Pham, X. D. (1998) New records of six black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 49 (2), 121 - 123.","Pham, X. D. (1999) Additional records of three black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 50 (4), 335 - 336."]}

Simulium (Gomphostilbia) lamdongense Takaoka & Sofian-Azirun, 2015 Simulium (Gomphostilbia) lamdongense Takaoka & Sofian-Azirun (in Takaoka et al., 2015a): 35���41 (Female, male, pupa and larva). Distribution. Vietnam (Lam Dong). Remark. This species was described from Lam Dong Province in southern Vietnam (Takaoka et al. 2015a)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 52, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

Simulium (Simulium) vietnamense Takaoka, Sofian-Azirun & Chen, 2014 Simulium (Simulium) vietnamense Takaoka, Sofian-Azirun & Chen (in Takaoka et al., 2014b): 743���746 (Female). Distribution. Vietnam (Vinh Phuc). Remarks. This species was described from two females collected while flying around a human in Tam Dao National Parks, Vinh Phuc Province (Takaoka et al. 2014b). The male, pupa and larva of this species are unknown., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 101, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 b) Female black flies of Simulium (Diptera: Simuliidae) collected on humans in Tam Dao National Park, Vietnam: Description of a new species and notes on four species newly recorded from Vietnam. Tropical Biomedicne, 31 (4), 742 - 748."]}

Simulium (Simulium) chungi Takaoka & Huang, 2006 Simulium (Simulium) chungi Takaoka & Huang, 2006: 219 ���227 (Female, male, pupa and larva); Takaoka et al. 2014b: 746. Distribution. Taiwan and Vietnam (Vinh Phuc). Remarks. This species was originally described from Taiwan (Takaoka and Huang 2006). The record from Vietnam was based on 14 females captured in Tam Dao National Park, Vinh Phuc Province, while flying around a human (Takaoka et al. 2014b). The aquatic stages remain to be collected from Vietnam., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 90, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Huang, Y. T. (2006) A new species of Simulium (Simulium) (Diptera: Simuliidae) from Taiwan. Medical Entomology and Zoology, 57 (3), 219 - 227.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 b) Female black flies of Simulium (Diptera: Simuliidae) collected on humans in Tam Dao National Park, Vietnam: Description of a new species and notes on four species newly recorded from Vietnam. Tropical Biomedicne, 31 (4), 742 - 748."]}

Simulium (Nevermannia) langbiangense Takaoka, Sofian-Azirun & Ya���cob, 2014 Simulium (Nevermannia) langbiangense Takaoka, Sofian-Azirun & Ya���cob (in Takaoka et al., 2014c): 556���563 (Female, male, pupa and larva). Distribution. Vietnam (Lam Dong). Remarks. This species was described from Lam Dong Province, southern Vietnam (Takaoka et al. 2014c). It is characterized by the female sensory vesicle with an enlarged opening., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 67, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2014 c) Three new species of Simulium (Nevermannia) (Diptera: Simuliidae) from Vietnam. Zootaxa, 3866 (4), 555 - 571."]}

Simulium (Montisimulium) nigrofilum Takaoka & Sofian-Azirun sp. nov. Female. Unknown. Male. Body length 3.1 mm. Head. As wide as thorax. Upper eye with large facets in 17 vertical columns and 19 horizontal rows. Face brownish black. Clypeus brownish black, densely covered with yellow short hairs interspersed with many dark-brown hairs. Antenna composed of scape, pedicel and nine flagellomeres, brownish black except scape and pedicel medium brown and base of first flagellomere whitish yellow; first flagellomere elongate, twice length of second one. Maxillary palp with five segments, light brown except third segment dark brown and first and second segments yellow, proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.1; third segment (Fig. 26 A) slender; sensory vesicle (Fig. 26 A) ellipsoidal, medium-long, 0.3 times length of third segment, and with small opening. Thorax. Scutum brownish black, densely covered with golden-yellow short hairs. Scutellum brownish black, with golden-yellow short hairs and dark-brown long upright hairs. Postnotum brownish black and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, and bare. Legs (coloration appearing incomplete, in particular all femora and tibia). Foreleg: coxa dark yellow; trochanter light brown; femur whitish yellow with apical cap dark brown; tibia dark brown except medial portion of outer surface paler: tarsus brownish black; basitarsus slightly flattened, 11.0 times as long as greatest width. Midleg: medium brown; trochanter light brown; femur light grayish with apical cap dark brown; tibia dark brown except median large area paler; tarsus dark brown to brownish black. Hind leg: coxa medium brown; trochanter dark yellow; femur light grayish with apical cap dark brown; tibia dark brown to brownish black except median large area paler; tarsus dark brown except basitarsus grayish to light brown; basitarsus (Fig. 26 B) somewhat enlarged, spindleshaped, 4.3 times as long as wide, and 0.9 and 0.9 times as wide as greatest widths of tibia and femur, respectively; calcipala (Fig. 26 B) well developed, as long as width at base; pedisulcus well developed. Wing. Length 2.2 mm. Costa with dark-brown spinules and light-brown hairs except basal patch of dark hairs mixed with yellow hairs. Subcosta with one or five hairs. Hair tuft on base of radius dark brown. Basal portion of radius fully haired. Basal cell absent. Halter. Light ochreous with basal portion darkened. Abdomen. Basal scale dark brown, with fringe of yellow long hairs. Dorsal surface of abdomen dark brown to brownish black, covered with yellow short hairs interspersed with dark hairs. Genitalia. Coxite in ventral view (Fig. 26 C) nearly rectangular, 2.1 times as long as its greatest width. Style in ventral view (Fig. 26 C) slender, curved inward, tapered from middle to apex, with apical spine; style in ventrolateral view (Fig. 26 D) 0.6 times as long as coxite, nearly parallel-sided from base to middle, then tapered toward apex; style in medial view (Fig. 26 E) boot-shaped, with apical portion twisted dorsally in form of triangular projection. Ventral plate in ventral view (Fig. 26 C) transverse, 0.4 times as long as greatest width at base, with body narrowed posteriorly, with anterior margin produced anteromedially, posterior margin greatly concave medially, and densely covered with microsetae on medial one-third of ventral surface; basal arms short, nearly parallel-sided, though slightly convergent apically; ventral plate in lateral view (Fig. 26 F) with apical portion of arms slightly curved dorsally; ventral plate in caudal view (Fig. 26 G) slightly rounded ventrally, with dorsal margin greatly concave medially, densely covered with microsetae medially on posterior surface. Median sclerite (Fig. 26 C, F, H), plate-like, narrowed toward middle, then widened toward apex, arising from level near anteromedial tip of ventral plate, and directed posteriorly. Paramere (Fig. 26 I) with four distinct hooks. Aedeagal membrane (Fig. 26 J) moderately covered with microsetae, and with weakly sclerotized dorsal plate in form of broad band. Ventral surface of abdominal segment 10 (Fig. 26 K, L) with two to five distinct hairs near posterior margin on each side. Cercus (Fig. 26 K, L) rounded, slightly produced ventrally, with eight to eleven hairs. Pupa. Body length 3.2 mm. Head. Integument including antennal sheaths yellow, densely covered with tubercles having few to several minute secondary projections; frons with two pairs of unbranched short trichomes with straight apices (one stout, one slender) (Fig. 27 A); face with pair of unbranched short stout trichomes with coiled apices (Fig. 27 B); two frontal trichomes on each side arising close together, and much shorter than facial ones. Thorax. Integument yellow, densely covered with tubercles bearing few to several minute secondary projections; thorax with three short anterodorsal trichomes (two stout, with coiled apices, one slender, with straight apex) (Fig. 27 C), two short slender anterolateral trichomes with straight apices (anterior one shorter than posterior one) (Fig. 27 D), one short stout mediolateral trichome with straight apex (Fig. 27 E), and three short ventrolateral trichomes with straight apices (anterior one slender, two others stout) (Fig. 27 F) on each side; all trichomes unbranched. Gill (Fig. 27 G) composed of 12 slender thread-like filaments, arranged in four groups (one inner, one middle dorsal, one middle ventral and one outer) arising from medium-long common basal stalk, which has transparent basal fenestra and 0.8 times length of interspiracular trunk; inner group composed of two filaments with short stalk, middle dorsal and ventral groups each composed of one individual and two paired filaments with short primary and medium-long secondary stalks, and outer group composed of two pairs of four filaments with short common stalk and medium-long secondary stalks; these two pairs lying vertically, one pair dorsal and another ventral; all filaments light brown except common basal stalk dark brown, subequal in length and thickness (though their exact length unmeasurable due to loss of apical portions) and tapered toward apices; cuticle of all filaments with well-defined annular ridges and furrows, and densely covered with minute tubercles, and with numerous darkbrown minute particles inside outer cuticular layer (Fig. 27 H). Abdomen. Dorsally, all segments yellowish; segments 1 and 2 with minute tubercles, segment 1 with one unbranched slender short hair-like seta (Fig. 27 I) on each side; segment 2 with one unbranched slender short hair-like seta and five short somewhat spinous setae submedially (Fig. 27 J) near posterior margin on each side; segments 3 and 4 each with four hooked spines and one short somewhat spinous seta near posterior margin on each side; segments 5���8 each with two unbranched short setae near posterior margin on each side; segments 6���8 each with spine-combs in transverse row; segments 5���9 each with comb-like groups of minute spines near anterior margin on each side; segment 9 with pair of cone-like terminal hooks (Fig. 27 K). Ventrally, segment 4 with few unbranched short setae on each side; segment 5 with pair of bifid hooks submedially and few unbranched short slender setae on each side; segments 6 and 7 each with pair of bifid inner and outer hooks somewhat spaced from each other and few unbranched short slender setae on each side; segments 4���8 each with comb-like groups of minute spines; segment 9 yellowish, covered sparsely with round small tubercles. Segment 9 with three grapnel-shaped hooklets (Fig. 27 L) on each lateral side. Cocoon (Fig. 27 M, N). Wall-pocket-shaped, thickly woven, not extended ventrolaterally, anterodorsal margin slightly produced anteriorly but without bulge or projection; posterior two-thirds with floor moderately woven; individual threads invisible; 3.0 mm long by 1.6���1.8 mm wide. Mature larva. Body length 6.2���6.6 mm. Body creamy except anterior and posterior surfaces of thoracic proleg, ventral surface of thoracic segments 2 and 3, and abdominal segments 1���4 light grayish-green, and with reddish-brown or ochreous markings as follows: thoracic segment 1 encircled with reddish-brown band though disconnected ventrally, thoracic segments 2 and 3 light reddish-brown dorsally and reddish brown ventrally, abdominal segment 1 encircled with light reddish-brown or ochreous band though disconnected dorsomedially, abdominal segments 2���4 each with pair of light reddish-brown or ochreous spots dorsally (though colored spots only on segments 3 and 4 in one larva and absent in one larva), abdominal segments 5���9 each with reddish-brown or ochreous markings entirely or partially covering dorsal surface, and those on segments 5 and 6 extended laterally and ventrally, though becoming lighter. Head. Head capsule yellow to dark yellow except areas in front of posterior margin on dorsal and lateral surfaces, and area above eyebrow on lateral surface much darkened, and median portion of ventral surface somewhat darkened, and with distinct head spots though anterior spots of posterolateral spots faint or absent, and sparsely covered with unpigmented minute setae (though moderately on dorsal surface); eyebrow distinct. Antenna composed of three articles and apical sensillum, longer than stem of labral fan; proportional lengths of first, second, and third articles 1.0:0.9:0.7���0.8; antennal article 2 light yellow, with three unpigmented annulations (Fig. 27 O). Labral fan with 35 primary rays. Mandible (Fig. 27 P) with three comb-teeth decreasing in length from first tooth to third, or second and third teeth subequal; mandibular serration composed of two teeth (one medium-sized, one small); major tooth at right angle against mandible on apical side; supernumerary serrations absent. Hypostoma (Fig. 27 Q) with row of nine apical teeth, of which median tooth as long as or slightly longer than each corner tooth; lateral margin serrate apically; five or six hypostomal bristles per side lying slightly divergent posteriorly from lateral margin. Postgenal cleft (Fig. 27 R) absent (or vestigial if any). Cervical sclerites composed of pair of small dark rod-like pieces. Thorax and Abdomen. Thoracic proleg without hairs; thoracic and abdominal cuticle almost bare except last abdominal segment densely covered with unbranched colorless setae on dorsolateral and lateral surfaces of each side of anal sclerite and on each lateral surface down to base of ventral papilla. Rectal scales present, unpigmented. Rectal organ compound, each of three lobes with several finger-like secondary lobules (exact number of secondary lobules uncountable). Anal sclerite of usual Xform, with anterior arms as long as or slightly longer than posterior ones, broadly sclerotized at base; no sensilla on broad base and posterior to posterior arms; accessory sclerite absent. Last abdominal segment with pair of large conical ventral papillae. Posterior circlet with 78 or 79 rows of hooklets with up to 16 or 17 hooklets per row. Type material. HOLOTYPE: Pharate male (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 31, Holotype, Simulium (M.) nigrofilum, Pharate male, coll. Vietnam, 20- XII-2014, Takaoka et al.], dissected out from a pupa collected from a small stream (width 0.5 m, bottom rocky, water temperature 11.0˚C, exposed to sun, elevation 1,750 m, 22˚21���43.110���N/103˚47���19.221���E) moderately flowing in a secondary forest, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian- Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. PARATYPES: One pupal exuviae and three mature larvae, same data as those of the holotype. in 80% ethanol, labeled in each vial as [UMSRP: Vietnam 0 31, Paratype, Simulium (M.) nigrofilum, coll. Vietnam, 20-XII-2014, Takaoka et al.] Biological notes. The pupae of this new species were collected from plastic sheets in the current. Associated species were S. (N.) tayense sp. nov., S. (S.) laocaiense sp. nov., S. (S.) sapaense sp. nov. and S. (S.) turgidum sp. nov. Distribution. Vietnam (Lao Cai). Etymology. The species name nigrofilum refers to the apparently black pupal gill filaments due to numerous minute black spots (Fig. 27 H). Remarks. This new species is characterized by the pupal gill with 12 filaments arranged in four groups (Fig. 27 G), and wall-pocket-shaped cocoon (Fig. 27 M, N). In the arrangement of the pupal gill, this species is most similar to S. (M.) angkaense Takaoka & Choochote from Thailand (Takaoka and Choochote 2005a, 2009) and S. (M.) nemorivagum Datta from India (Datta 1973). This new species is distinguished from S. (M.) angkaense and S. (M.) nemorivagum by the male upper-eye facets in 17 vertical columns and 19 horizontal rows (20 vertical columns and 22 horizontal rows in S. (M.) angkaense, and 12 vertical columns and 14 horizontal rows in S. (M.) nemorivagum), and also from S. (M.) angkaense in the pupa by the presence of grapnel-shaped hooklets on each side of abdominal segment 9 (Fig. 27 L)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 61-65, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Choochote, W. (2005 a) Discovery of two more new species of Simulium (Montisimulium) (Diptera: Simuliidae) in Doi Inthanon National Park, Chiang Mai, Thailand. Tropical Medicine and Health, 33 (4), 209 - 215.","Takaoka, H. & Choochote, W. (2009) Description of the female and male of Simulium (Montisimulium) angkaense (Diptera: Simuliidae) from Thailand. Medical Entomology and Zoology, 60 (2), 113 - 118. https: // doi. org / 10.7601 / mez. 60.113","Datta, M. (1973) New species of black flies (Diptera: Simuliidae) of the subgenera Eusimulium Roubaud and Gomphostilbia Enderlein from the Darjeeling area, India. Oriental Insects, 7, 363 - 402."]}

Simulium (Simulium) chamlongi Takaoka & Suzuki, 1984 Simulium (Simulium) chamlongi Takaoka & Suzuki, 1984: 27 ���30 (Female, male, pupa and larva); Crosskey and Howard, 1997; Pham, 1999: 335; Takaoka et al., 2015a: 93. Distribution. Thailand and Vietnam (Bac Thai and Lam Dong). Remarks. This species was originally described from Thailand by Takaoka and Suzuki (1984) and later recorded from Vietnam by Crosskey and Howard (1997), Pham (1999) and Takaoka et al. (2015a). No detailed information for the locality was given by Crosskey and Howard (1997). Simulium (Simulium) phuluense Takaoka & Sofian-Azirun sp. nov. Female. Body length 2.6���3.1 mm. Head. Narrower than thorax. Frons black, shiny, with several dark long stout hairs along each lateral margin and three to five similar hairs on each side just above lower margin; frontal ratio 1.3:1.0:1.2���1.4; frons:head ratio 1.0:3.6���4.3. Fronto-ocular area well developed, short, directed laterally and slightly upward. Clypeus black, white pruinose, slightly shiny when illuminated at certain angles, moderately covered with dark-brown long stout hairs except mediolongitudinal area of upper half somewhat widely bare. Labrum 0.7 times as long as clypeus. Antenna composed of scape, pedicel and nine flagellomeres, medium to dark brown except scape, pedicel and base of first flagellomere yellow when viewed dorsally, and scape, pedicel and basal four-fifths of flagellomere yellow when viewed ventrally. Maxillary palp with five segments, grayish brown except segments 1 and 2 yellow; proportional lengths of third, fourth, and fifth segments 1.0:1.3:2.8���3.1; third segment (Fig. 69 A) of normal size; sensory vesicle (Fig. 69 A) of moderate size, (0.3���0.4 times length of third segment) having opening of moderate size. Maxillary lacinia with 13 or 14 inner and 16 or 17 outer teeth. Mandible with 30���32 inner and 16 outer teeth. Cibarium (Fig. 69 B) with blunt medial projection on posterior margin and with about 30 small pointed processes and about 28 minute ones near base of medial projection. Thorax. Scutum black, white pruinose along lateral margins, shiny when illuminated at certain angles, densely covered with goldenyellow recumbent short hairs interspersed with several dark-brown long upright hairs on prescutellar area. Scutellum dark brown, covered with dark-brown upright long hairs and golden-yellow short hairs. Postnotum brownish black, white pruinose when illuminated at certain angles and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, shiny and white pruinose when illuminated at certain angles and bare. Legs. Foreleg: coxa whitish yellow; trochanter yellow; femur yellow except apical cap light brown; tibia yellowish white except basal one-fourth light brown and apical cap brownish black, with shiny sheen widely on outer surface when illuminated at certain angles; tarsus brownish black, with moderate dorsal hair crest; basitarsus greatly dilated, 5.6���5.8 times as long as its greatest width. Midleg: coxa brownish black; trochanter yellow; femur yellow with apical cap light brown; tibia (Fig. 69 C) whitish yellow to dark yellow except apical cap medium brown and narrow portion of outer surface along posterior margin widely light to medium brown, and with shiny sheen on posterior surface when illuminated at certain angles; tarsus medium brown except basal half to two-thirds of basitarsus yellow. Hind leg: coxa dark brown; trochanter yellow; femur yellow with apical cap medium brown; tibia (Fig. 69 D) yellow on little less than basal half, and gradually darkened toward apex and apical cap dark brown on outer and posterior surface, and widely yellow except apical cap dark brown on inner surface, with shiny sheen on posterior surface when illuminated at certain angles; tarsus medium brown except basal two-thirds of basitarsus and basal half of second tarsomere yellow; basitarsus (Fig. 69 E) nearly parallel-sided, 6.2���6.3 times as long as wide, and 0.7���0.8 and 0.6���0.7 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 69 E) moderately developed, slightly shorter than basal width, and 0.5 times as wide as basitarsus; pedisulcus (Fig. 69 E) well developed; claw (Fig. 69 F) with small subbasal tooth. Wing. Length 2.7���3.1 mm. Costa with dark spinules and hairs; subcosta haired except near apex bare; basal section of radius bare; R1 with dark spinules and hairs; R2 with hairs; hair tuft on base of radial vein dark brown; basal cell absent. Halter. White with basal portion darkened. Abdomen. Basal scale light brown, with fringe of pale long hairs. Dorsal surface of abdomen medium brown except segment 2 light brown, with short dark hairs; tergite 2 shiny, white iridescent when illuminated at certain angles, and tergites 6���8 shiny; ventral surface of segment 2 whitish and those of others light brown; segment 7 with median large sternal plate having numerous hairs. Terminalia. Sternite 8 (Fig. 69 G) bare medially, with 22���25 dark medium-long to long stout hairs on each lateral surface. Ovipositor valves (Fig. 69 G) wide, with inner margins widely concave, with posteromedial apices pointed anteriorly, each moderately covered with microsetae and 35 or 36 short to medium-long hairs except small area of posteromedial apex bare; inner margins widely concave and darkened except near apex unpigmented. Genital fork (Fig. 69 H) of inverted-Y form, with narrow, well sclerotized stem; arms of moderate width, each with distinct short projection directed anterodorsally. Paraproct in ventral view (Fig. 69 I) oblong, widely depressed on ventral surface, unpigmented except medial surface somewhat darkened, sparsely covered with minute setae and sensilla; paraproct in lateral view (Fig. 69 J) much protruded ventrally beyond ventral margin of cercus, 0.7 times as long as wide, with numerous short to medium-long hairs on lateral and ventral surfaces; anteromedial surface with 10 or 11 short sensilla. Cercus in lateral view (Fig. 69 J) short, trapezoid, 0.48 times as long as wide, and with numerous short to medium-long hairs. Spermatheca (Fig. 69 K) large, nearly ovoid, 1.3 times as long as wide, well sclerotized except portion of juncture with duct unsclerotized, with no defined surface patterns, and with internal setae; accessory ducts subequal in thickness to each other, and to major duct. Male. Body length 3.0��� 3.3 mm. Head. Nearly as wide as thorax. Upper eye medium brown, consisting of large facets in 23 or 24 vertical columns and in 23 or 24 horizontal rows. Clypeus black, thickly white pruinose, moderately covered with dark-brown hairs. Antenna composed of scape, pedicel and nine flagellomeres, dark brown except base of first flagellomere light brown; first flagellomere elongate, 1.6 times as long as second one. Maxillary palp medium brown, composed of five segments with proportional lengths of third, fourth, and fifth segments 1.0:1.2:2.5; third segment (Fig. 70 A) of moderate size, with apex somewhat produced inward; sensory vesicle (Fig. 70 A) small (0.2 times length of third segment), ellipsoidal, and with small opening. Thorax. Nearly as in male of S. (S.) daoense sp. nov. Legs . Foreleg: coxa yellow; trochanter light brown; femur light to medium brown with apical cap dark brown; tibia brownish black except middle one-third medium brown, though outer surface widely white except basal tip and apical cap, and with white sheen when illuminated at certain angles; tarsus brownish black, with moderate dorsal hair crest; basitarsus moderately dilated, 6.7���7.7 times as long as its greatest width. Midleg: dark brown to brownish black except extreme base of tibia whitish yellow and basal half of basitarsus yellow. Hind leg: coxa brownish black; trochanter light brown; femur medium brown except base light brown or dark yellow and apical cap brownish black; tibia dark brown to brownish black except basal tip whitish yellow; tarsus (Fig. 70 B) medium brown except basal half to two-fifths of basitarsus yellow (though base somewhat darkened) and little less than basal half of second tarsomere yellow; basitarsus (Fig. 70 B) much enlarged, spindle-shaped, gradually widened from base to apical one-third, then tapered to apex, 4.3 times as long as its greatest width, and 0.8 and 0.9���1.0 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 70 B) small, slightly shorter than width at base, 0.3 times as wide as greatest width of basitarsus; pedisulcus (Fig. 70 B) well developed. Wing. Length 2.7���2.9 mm. Other characters as in female including subcosta with 12���24 hairs though apical one-fifth and one-third bare. Halter. White with basal portion darkened. Abdomen. Basal scale dark brown to brownish black, with fringe of dark long hairs. Dorsal surface of abdomen dark brown to brownish black, and covered with dark short hairs; segments 2 and 5���7 each with pair of silvery or bluish iridescent spots dorsolaterally, those on segment 2 broadly connected in middle to each other. Genitalia. Coxites, styles and ventral plate in ventral view as Fig. 70 C. Coxite in ventral view nearly quadrate, 1.2 times as long as width. Style in ventrolateral view (Fig. 70 D) elongate, 3.48 times as long as its greatest width near base, slightly tapered to apex; style in medial view (Fig. 70 E) 1.6 times as long as coxite, spatulate dorsoventrally except basal half much produced dorsally in form of isosceles triangular. Ventral plate in ventral view (Fig. 70 C) Y-shaped, body with several teeth on each side of posterior surface, and with ventrally produced process covered with several minute setae on its ventroposterior surface; arms widely divergent basally and convergent apically; ventral plate in lateral view (Fig. 70 F): body with serrated posterior margin, and sparsely covered with minute setae on each anterolateral surface, and having ventrally produced process with anterolateral surface bare except several minute setae near base; arm wide with apex curved ventrally; ventral plate in caudal view (Fig. 70 G): body and ventrally produced process gradually tapered ventrally, with round apex, having seven to nine teeth on each side of posterior surface, and several minute setae on posterior surface of ventrally produced process. Median sclerite (Fig. 70 F, H) arising near anterior margin of ventral plate and directed dorsally, plate-like, widened from base toward apical one-third, then nearly parallel-sided or slightly narrowed toward apex, brown basally, but not so well sclerotized apically. Paramere (Fig. 70 I) broad basally, with several long hooks and shorter ones. Aedeagal membrane (Fig. 70 J) densely covered with minute setae, and with partially sclerotized dorsal plate in form of horizontal bar (Fig. 70 K). Abdominal segment 10 (Fig. 70 L, M) without distinct hair on ventral and lateral surfaces. Cercus (Fig. 70 L, M) small, rounded, with 14���16 distinct hairs. Pupa. Body length 2.7���3.2 mm. Head. Integument yellow to ochreous, moderately covered with small round tubercles except antennal sheath bare; frons with pair of unbranched slender short trichomes (Fig. 71 A) on each side; face with unbranched slender short trichome (Fig. 71 B) on each side. Thorax. Integument yellow to ochreous, moderately covered with small round tubercles; thorax with two long anterodorsal trichomes (Fig. 71 C), two anterolateral trichomes (anterior trichome medium-long, and posterior trichome long) (Fig. 71 D), one mediumlong mediolateral trichome (Fig. 71 E), and three ventrolateral trichomes (one short, two others medium-long) (Fig. 71 F), on each side; all unbranched and with straight apices. Gill (Fig. 71 G) with six slender thread-like short filaments in three pairs; all pairs short-stalked, arising from short common basal stalk; gill filaments divergent basally, upper filament of dorsal pair lying at angle of 120 degrees against lower filament of ventral pair when viewed laterally; filaments subequal in length to one another (2.2���2.4 mm long) (though lower filament of middle pair and upper filament of ventral pair somewhat longer (2.7 mm long); relative thickness of six filaments from dorsal to ventral when basal portions were compared 1.0:0.9:1.0:1.0:0.8:0.8; all filaments light to medium brown, tapered toward apex, with distinct annular ridges and furrows forming definite reticulate surface patterns, and densely covered with minute tubercles (relatively larger ones on ridges). Abdomen. Dorsally, segment 1 and basal half of segment 2 light brown and without minute tubercles, and other segments unpigmented except segment 9 and basal portions of spine-combs on segments 7 and 8 yellow; segment 1 with one unbranched slender short seta (Fig. 71 H) on each side; segment 2 with one unbranched slender short seta and five unbranched short setae, of which four are stout (Fig. 71 I), on each side; segments 3 and 4 each with four distinct hooked spines and one unbranched short seta on each side; segments 7 and 8 each with distinct spine-combs in transverse row on each side; segments 5, 6 and 9 lacking spine-combs; segments 6���9 each with comb-like groups of minute spines on each side; segment 9 with cone-shaped terminal hooks (Fig. 71 J). Ventrally, segments 3���9 unpigmented, each (except segment 9) with comb-like groups of minute spines; segment 4 with one unbranched slender minute seta, two stout hooklets (Fig. 71 K) on each side; segment 5 with pair of bifid stout hooks submedially and few unbranched short setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer stout hooks somewhat separated from each other, and few unbranched short setae on each side. Grapnel-shaped hooklets absent on each side of segment 9. Cocoon. Wall-pocket-shaped, tightly and thickly woven, ochreous, not so extended ventrolaterally; individual threads invisible; 3.5���4.5 mm long by 1.6���2.2 mm wide. Mature larva. Body length 7.4���8.4 mm. Body whitish to light grayish, and thoracic segment 1 encircled with pinkish to reddish-brown transverse band though disconnected ventromedially, and other thoracic segments and abdominal segments pinkish to light ochreous dorsally to varying extent. Head. Cephalic apotome yellowish white to yellow with somewhat darkened narrow area along posterior margin; head spots faintly positive though anterior spot of mediolongitudinal spots often less distinct; lateral surface of head capsule yellow except eye-spot region yellowish white and eyebrow darkened and area between eye-spot region and posterior margin always darkened though spots in front of posterior margin obscured or faintly negative; one small spot below eye-spot region indistinct; ventral surface of head capsule (Fig. 72 A) yellow to light brown, with spots on each side of postgenal cleft obscured or faintly negative. Head capsule sparsely covered with minute setae on dorsal, lateral and ventral surfaces. Antenna composed of three articles and apical sensillum, slightly longer than stem of labral fan; length ratio of three articles (from base to tip) 1.0:1.1���1.2:0.6���0.7. Labral fan with 49���51 primary rays. Mandible (Fig. 72 B) with mandibular serration composed of two teeth (one medium-sized, one small); main tooth at obtuse angle against mandible on apical side; supernumerary serrations absent; comb-teeth decreasing in length from first to third. Hypostoma (Fig. 72 C) with nine anterior teeth, of which corner teeth slightly longer than median tooth; three intermediate teeth on each side shortest; lateral margins moderately serrate apically; six hypostomal bristles per side divergent posteriorly from lateral margin. Postgenal cleft (Fig. 72 A) medium-sized, 2.1 times as long as postgenal bridge, pointed apically; sheath of subesophageal ganglion usually weakly pigmented, wine-glassshaped, or not pigmented. Cervical sclerites on each side composed of anterior dark slender rod-like piece and posterior dark elliptical piece close together, and not fused to occiput. Thorax and Abdomen. Histoblast of pharate pupal gill with six thread-like filaments. Thoracic and abdominal cuticle bare except last segment of abdomen moderately covered with short colorless setae on each side of anal sclerite. Rectal scales present. Rectal organ compound, each lobe with 18���21 finger-like secondary lobules. Anal sclerite X-shaped, with short broad anterior arms with forked apices, 0.8 times as long as posterior ones; no or one sensillum on base of anal sclerite; four to nine sensilla posterior to posterior arms. Last abdominal segment lacking ventral papillae. Posterior circlet with 88���95 rows of hooklets with up to 13 or 14 hooklets per row. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 46, Holotype, Simulium (S.) phuluense , Female, coll. Vietnam, 23-XII-2014, Takaoka et al.], reared from a pupa collected from a small shallow stream (width 2.0 m, depth 15 cm, bottom of pebbles, water temperature 9.0˚C, partially shaded, elevation 1,192 m, 22˚23���03.208���N/103˚50���58.990���E) moderately flowing in a natural forest, Sapa, Lao Cai Province, northern Vietnam, 23-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. PARATYPES: Three females, four males (all reared from pupae) and five mature larvae in 80% ethanol, same data as those of the holotype, labeled in each vial as [UMSRP: Vietnam 0 46, Paratype, Simulium (S.) phuluense , coll. Vietnam, 23-XII-2014, Takaoka et al.]. Biological notes. The pupae and larvae of S. (S.) phuluense sp. nov. were collected from grass leaves and roots trailing in the current. This species is one of the dominant species in Sapa, being found in 12 of 23 streams surveyed. Associated species were S. (G.) hongthaii, S. (S.) daoense sp. nov., S. (S.) doipuiense (complex) and S. (S.) sapaense sp. nov. Distribution. Vietnam (Lao Cai). Etymology. The species name phuluense refers to the land in which the tribe Phulu lives. Remarks. Simulium (S.) phuluense sp. nov. is assigned to the S. variegatum species-group of the subgenus Simulium, redefined by Takaoka (2003), based on the pleural membrane bare, female claw with a small subbasal tooth (Fig. 69 F), ovipositor valves with inner margins widely concave (Fig. 69 G), male style without basal protuberance (Fig. 70 E), pupal gill with six filaments (Fig. 71 G). This new species is characterized by a greater number of the upper-eye facets in 23 or 24 vertical columns and 23 or 24 horizontal rows, and haired subcosta in the male. No other related species of the S. variegatum speciesgroup have such a combination of characters except S. (S.) oitanum (Shiraki) (reported as S. (Odagmia) aokii) from Koshiki Island, Nansei Islands, Japan, which has the male subcosta with 10���12 hairs, although it has the male upper-eye facets in about 16 horizontal rows (Takaoka 1976). Simulium (S.) zunyie, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 154-160, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Suzuki, H. (1984) The blackflies (Diptera: Simuliidae) from Thailand. Japanese Journal of Sanitary Zoology, 35 (1), 7 - 45.","Crosskey, R. W. & Howard, T. H. (1997) A New Taxonomic and Geographical Inventory of World Black Flies (Diptera: Simuliidae). Natural History Museum, London, 144 pp.","Pham, X. D. (1999) Additional records of three black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 50 (4), 335 - 336.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96.","Takaoka, H. (1976) Studies on blackflies of the Nansei Islands, Japan (Simuliidae; Diptera). II. On six species of the subgenera Gomphostilbia Enderlein, Morops Enderlein, Odagmia Enderlein and Gnus Rubzov, with the description of Simulium (Gomphostilbia) okinawense sp. nov. Japanese Journal of Sanitary Zoology, 27, 385 - 398. https: // doi. org / 10.7601 / mez. 27.385","Chen, H. B., Xiu, J. F. & Zhang, C. L. (2012) A survey of blackflies with three new species from Kuankuoshui, Guizhou, China (Diptera, Simuliidae). Acta Zootaxonomica Sinica, 37 (2), 382 - 388.","Cai, R., An, J. Y. & Li, C. P. (2008) A new species of the subgenus Simulium from Sichuan, China (Diptera: Simuliidae). Acta Parasitologica Medica and Entomologica Sinica, 15 (2), 100 - 102.","Liu, Z. J. & An, J. Y. (2009) A new species of Simulium (Diptera: Simuliidae) from Shaanxi, China. Entomotaxonomica, 31 (2), 143 - 146."]}

Simulium (Gomphostilbia) longlanhense Takaoka & Ya���cob, 2015 Simulium (Gomphostilbia) longlanhense Takaoka & Ya���cob (in Takaoka et al., 2015a): 41���48 (Female, male, pupa and larva). Distribution. Vietnam (Lam Dong). Remark. This species was described from Lam Dong Province in southern Vietnam (Takaoka et al. 2015a)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 52, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

4) Simulium darjeelingense species-group Simulium (Gomphostilbia) eshimai Takaoka & Adler sp. nov. Female. Body length 2.0 mm. Head. Slightly narrower than thorax. Frons brownish black, densely covered with yellow scale-like recumbent short hairs and few dark hairs along each lateral margin; frontal ratio 1.8:1.0:1.8; frons:head ratio 1.0:3.7. Fronto-ocular area well developed, narrow, directed dorsolaterally. Clypeus brownish black, slightly white pruinose, and densely covered with yellowish-white recumbent hairs interspersed with several dark longer hairs on each side. Labrum 0.8 times as long as clypeus. Antenna composed of scape, pedicel and nine flagellomeres, dark brown, though scape, pedicel and base of first flagellomere slightly lighter. Maxillary palp composed of five segments, light brown except third segment dark brown, proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.2; third segment (Fig. 22 A) somewhat enlarged; sensory vesicle (Fig. 22 A) elongate, 0.5 times length of third segment and with medium-sized opening. Maxillary lacinia with 13 or 14 inner and 20 outer teeth. Mandible with 36 inner teeth and four or five outer teeth at some distance from apex. Cibarium (Fig. 22 B) with dorsal margin having short plate produced forward and downward, and with weakly-sclerotized mediolongitudinal stripe bearing well-sclerotized U-shaped ridge apically. Thorax. Scutum brownish black, slightly shiny when illuminated at certain angles, densely covered with yellow scale-like recumbent hairs mixed with whitish similar hairs on peripheral portions. Scutellum dark brown, covered with yellow short hairs and darkbrown long upright hairs. Postnotum brownish black, white pruinose and slightly shiny when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, dark brown, white pruinose and shiny when illuminated at certain angles, moderately covered with pale and dark short hairs. Legs. Foreleg: coxa yellow; trochanter light brown except base yellow; femur medium brown with apical cap dark brown (though extreme tip yellow); tibia medium brown except base yellow and apical cap dark brown, though median portion of outer surface widely lighter; tarsus brownish black to black, with moderate dorsal hair crest; basitarsus somewhat dilated, 7.0 times as long as its greatest width. Midleg: coxa medium brown except posterolateral surface dark brown; trochanter light brown except base yellow; femur medium brown except basal one-fourth yellow and apical cap medium brown (though extreme tip yellow); tibia medium to dark brown except extreme base yellow and apical cap brownish black; tarsus dark brown to brownish black, though base of basitarsus somewhat lighter. Hind leg: coxa medium brown; trochanter yellow; femur light to medium brown except base yellow and apical cap dark brown (though extreme tip yellow); tibia light to medium brown except base yellow, apical cap dark brown and subbasal portion medium to dark brown; tarsus (Fig. 22 C) dark brown except basal two-thirds of basitarsus (though base light brown) and little less than basal half of second tarsomere whitish; basitarsus (Fig. 22 C) narrow, slightly narrowed toward apex, 7.6 times as long as wide, and 0.64 and 0.54 times as wide as greatest widths of tibia and femur, respectively; calcipala (Fig. 22 C) well developed, slightly longer than wide, and 0.6 times as wide as greatest width of basitarsus; pedisulcus (Fig. 22 C) well developed; claw (Fig. 22 D) with large basal tooth 0.5 times length of claw. Wing. Length 1.5 mm. Costa with dark-brown spinules and light-brown hairs except basal patch of yellow hairs. Subcosta haired except near apex bare. Hair tuft on base of radius dark brown intermixed with several yellow hairs. Basal portion of radius fully haired. Basal cell absent. Halter. Creamy except basal stem darkened. Abdomen. Basal scale grayish yellow, with fringe of yellowish-white hairs. Dorsal surface of abdomen medium brown except segment 2 grayish yellow though tergal plate medium brown, and moderately covered with dark short to long hairs; tergites of segments 2 and 6���9 shiny when illuminated at certain angles. Ventral surface of segment 2 creamy, those of other segments ochreous except sternite 8 dark brown; sternal plate on segment 7 undeveloped. Terminalia. Sternite 8 (Fig. 22 E) bare medially, with 12���14 medium-long to long hairs together with few slender short hairs on each side. Ovipositor valve (Fig. 22 E) triangular (though posteromedial corner appearing to be truncated), thin, membranous, moderately covered with microsetae interspersed with three or four short hairs; inner margins nearly straight or sinuous, with small depression subapically, moderately sclerotized, and somewhat separated from each other. Genital fork (Fig. 22 F) of usual inverted-Y form, with slender stem; arms of moderate width, with lateral plate angulated anterodorsally. Paraproct in ventral view (Fig. 22 G) with anteromedian margin slightly raised ventrally, with unpigmented anteromedial surface having four or five sensilla; paraproct in lateral view (Fig. 22 H) much produced ventrally, 0.6 times as long as wide, with 18 or 19 medium-long to long hairs on ventral and lateral surfaces. Cercus in lateral view (Fig. 22 H) short, rounded posteriorly, 0.5 times as long as wide. Spermatheca (Fig. 22 I) ellipsoidal, 1.6 times as long as greatest width, well sclerotized except duct and small area near juncture with duct unsclerotized, and with many fissures on surface; internal setae absent; both accessory ducts slender, subequal in diameter to major one. Male. Body length 2.2���2.5 mm. Head. As wide as thorax. Upper eye medium brown, with large facets in 16 or 17 vertical columns and 17 horizontal rows. Face brownish black, whitish-gray pruinose when illuminated at certain angles. Clypeus brownish black, whitish-gray pruinose when illuminated at certain angles, and moderately covered with yellow short hairs interspersed with 12���16 dark-brown longer hairs on each side. Antenna composed of scape, pedicel and nine flagellomeres, brownish black except base of first flagellomere light brown; first flagellomere elongate, twice length of second one. Maxillary palp with five segments, light brown except third segment dark brown, proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.1; third segment (Fig. 23 A) somewhat widened apically; sensory vesicle (Fig. 23 A) ellipsoidal, medium-long, 0.3 times length of third segment, and with opening of medium-size. Thorax. Scutum black, slightly shiny when illuminated at certain angles, densely covered with golden-yellow short hairs. Scutellum brownish back, with golden-yellow short hairs and dark-brown long upright hairs. Postnotum brownish black and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, thinly pruinose and slightly shiny when illuminated at certain angles, moderately covered with dark hairs. Legs. Foreleg: coxa and trochanter medium brown; femur medium brown with apical cap dark brown; tibia medium brown except apical cap dark brown and medial portion of outer surface light brown: tarsus brownish black; basitarsus slightly flattened, 9.1 times as long as greatest width. Midleg: coxa dark brown except posterolateral surface brownish black; trochanter medium brown; femur medium brown with apical cap dark brown (though extreme tip somewhat paler); tibia medium brown except base dark yellow and apical cap dark brown, and with golden-yellow short hairs on posterior surface of basal one-third; tarsus dark brown to brownish black. Hind leg: coxa dark brown; trochanter light brown; femur medium brown with apical cap dark brown (though extreme tip yellow); tibia medium brown to brownish black except base dark yellow to light brown; tarsus dark brown except basitarsus grayish to light brown and little less than basal half of second tarsomere whitish; basitarsus (Fig. 23 B) enlarged, spindle-shaped, 4.2 times as long as wide, and 0.9 and 1.0 times as wide as greatest widths of tibia and femur, respectively; calcipala (Fig. 23 B) well developed, slightly longer than width at base, and 0.4 times as wide as greatest width of basitarsus; pedisulcus (Fig. 23 B) well developed. Wing. Length 2.2 mm. Other characters as in female except costa without basal patch of yellow hairs, subcosta bare, and hair tuft on base of radius dark brown. Halter. Ochreous with basal portion darkened. Abdomen. Basal scale brownish black, with fringe of dark-brown long hairs. Dorsal surface of abdomen dark brown to brownish black, covered with lightbrown short to long hairs; segments 2, 6 and 7 each with pair of shiny dorsolateral patches, when illuminated at certain angles; ventral surface of segment 2 grayish white, those of other segments medium to dark brown. Genitalia. Coxite in ventral view (Fig. 23 C) nearly rectangular, 1.7 times as long as its greatest width. Style in ventral view (Fig. 23 C) slender, curved inward, tapered toward middle, with apical spine; style in ventrolateral view (Fig. 23 D) 0.9 times as long as coxite, tapered from base to middle, then nearly parallel-sided toward apex, with round apex. Ventral plate in ventral view (Fig. 23 C) transverse, 0.7 times as long as greatest width at base, with body narrowed posteriorly, with anterior margin produced anteromedially, posterior margin concave medially, and densely covered with microsetae on ventral surface except anterolateral areas bare; basal arms of moderate length, somewhat divergent, then convergent apically; ventral plate in lateral view (Fig. 23 E) with posterior portion of body not produced ventrally; ventral plate in caudal view (Fig. 23 F) slightly rounded ventrally (width:height=1.0:0.3), with dorsal margin concave medially, densely covered with microsetae on posterior surface. Median sclerite (Fig. 23 C, E, G) plate-like, arising from level near anteromedial tip of ventral plate, and directed dorsally. Paramere (Fig. 23 H) with four distinct hooks. Aedeagal membrane (Fig. 23 H) moderately covered with microsetae, and with no sclerotized dorsal plate. Ventral surface of abdominal segment 10 (Fig. 23 I, J) without distinct hair near posterior margin on each side. Cercus (Fig. 23 I, J) rounded, slightly produced ventrally, with 17 or 18 hairs. Pupa. Body length 2.3���2.5 mm. Head. Integument yellow, moderately covered with small round tubercles except most of ventral surface of face bare; antennal sheath without tubercles; frons with three pairs of unbranched long trichomes with straight apices; face with two pairs of unbranched long trichomes with straight apices (Fig. 24 A); three frontal trichomes on each side arising close together, subequal in length to one another and nearly as long as or somewhat longer than facial ones. Thorax (Fig. 24 B). Integument yellow, moderately covered with round tubercles on anterior one-third, and almost bare on other portion except dorsal surface near posterior margin sparsely covered with small tubercles; thorax with three long anterodorsal trichomes with coiled or straight apices, two anterolateral trichomes with straight apices (anterior one medium-long, posterior one long), one long mediolateral trichome with straight apex, and three ventrolateral trichomes with straight apices (anterior one medium-long, two others long) on each side; all trichomes unbranched. Gill (Fig. 24 B, C) composed of eight slender thread-like filaments, arranged in three groups (one dorsal, one ventral inner and one ventral outer) arising from short common basal stalk, which has somewhat swollen basal fenestra; dorsal group composed of three filaments all arising upward at same level from short stalk, ventral inner group composed of one individual and two paired filaments with short primary and secondary stalks, or all three filaments arising forward at same level from short stalk, and ventral outer group composed of two paired filaments with short stalk; all filaments light brown, subequal in length (0.7���1.0 mm) and thickness to one another except ventral filament of ventral pair somewhat thicker than others when compared basally; cuticle of all filaments without annular ridges and furrows, and densely covered with minute tubercles. Abdomen. Dorsally, all segments nearly unpigmented and without tubercles except segments 1 and 2 pale yellowish, and segment 9 and basal portions of spine-combs on segments 6���9 yellowish; segment 1 with one unbranched slender medium-long hair-like seta on each side; segment 2 with one unbranched slender medium-long or short hair-like seta and five short somewhat spinous setae submedially near posterior margin on each side; segments 3 and 4 each with four hooked spines and one short somewhat spinous seta near posterior margin on each side; segments 5���8 each with two or three unbranched short setae near posterior margin on each side; segments 6���9 each with spine-combs in transverse row and comb-like groups of minute spines near anterior margin; segment 9 with pair of cone-like terminal hooks (Fig. 24 D). Ventrally, segment 4 with one unbranched hook and few unbranched short setae on each side; segment 5 with pair of bifid or trifid hooks submedially and few unbranched short slender setae on each side; segments 6 and 7 each with pair of bifid or trifid inner and unbranched outer hooks somewhat spaced from each other and few unbranched short slender setae on each side; segments 4���8 with comb-like groups of minute spines. Each side of segment 9 with three grapnel-shaped hooklets. Cocoon (Fig. 24 E). Wall-pocket-shaped, moderately woven, widely extended ventrolaterally; anterior margin thickly woven, without anterodorsal bulge or projection; posterior half with floor roughly or moderately woven; individual threads visible; 3.0 mm long by 2.6���2.8 mm wide. Mature larva. Body length 4.0��� 4.6 mm. Body light ochreous except anterior surface of thoracic proleg, thoracic segment 3 (except ventral surface light ochreous) and abdominal segments 1���4 entirely greenish, and ventral surface of abdominal segments 5���9 creamy (though light-ochreous transverse band on ventral surface of segment 7). Head. Head capsule whitish yellow, with no distinct head spots, and sparsely covered with unpigmented minute setae (though moderately on dorsal surface); ventral surface slightly darkened near lateral margins of postgenal cleft, and with negative elongate spot on each side of postgenal cleft. Antenna composed of three articles and apical sensillum, longer than stem of labral fan; proportional lengths of first, second, and third articles 1.0:0.8:0.7���0.8. Labral fan with 42 primary rays. Mandible (Fig. 25 A) with three comb-teeth decreasing in length from first tooth to third; mandibular serration composed of two teeth (one medium-sized, one small); major tooth at acute angle against mandible on apical side; supernumerary serrations absent. Hypostoma (Fig. 25 B) with row of nine apical teeth, of which median tooth is longer than each corner tooth; lateral margin smooth; four or five hypostomal bristles per side lying nearly parallel to or slightly divergent posteriorly from lateral margin. Postgenal cleft (Fig. 25 C) arrow-head-shaped, long, 4.2 times length of postgenal bridge. Cervical sclerites composed of pair of small yellow rod-like pieces. Thorax and Abdomen. Thoracic proleg without hairs; thoracic cuticle moderately covered with dark setae with two to five branches (majority of setae with three or four branches) interspersed with unbranched colorless setae (similar to those in Fig. 25 D) on dorsal surface, abdominal cuticle of segments 1���4 sparsely covered with similar branched dark minute setae on dorsal surface, and that of segments 5���9 densely covered with dark minute setae each with two to eight branches (majority of setae with four to six branches) interspersed with unbranched colorless setae (Fig. 25 D) on dorsal and dorsolateral surfaces, even on dorsal surface of each side of anal sclerite; last abdominal segment densely covered with unbranched colorless longer setae on dorsolateral and lateral surfaces of each side of anal sclerite and on each lateral surface down to base of ventral papilla; thorax and abdomen without dorsal protuberances. Rectal scales present, unpigmented. Rectal organ compound, each of three lobes with several finger-like secondary lobules (exact number of secondary lobules uncountable). Anal sclerite of usual X-form, with anterior arms 1.1 times length of posterior ones, broadly sclerotized at base; no sensilla on broad base and posterior to posterior arms; accessory sclerite absent. Last abdominal segment with pair of large conical ventral papillae. Posterior circlet with 85���88 rows of hooklets with up to 13 or 14 hooklets per row. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 30, Holotype, Simulium (G.) eshimai , Female, coll. Vietnam, 20-XII-2014, Takaoka et al.], reared from a pupa collected from a river (width 6 m, depth 0.6 m, bottom rocky, water temperature 11.0˚C, exposed to the sun, elevation 1,728 m, 22˚22���22.719���N/103˚45���24.852���E) fast-flowing in forest, Lai Chau, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. PARATYPES: Two males, three pupal exuviae, one mature larva, same data as those of the holotype in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 30, Paratype, Simulium (G.) eshimai, coll. Vietnam, 20- XII-2014, Takaoka et al.]; one mature larva in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 30, Paratype, Simulium (G.) eshimai, coll. Vietnam, 20-XII-2014, Takaoka et al.], collected from a small cascading stream (width 2.5 m, depth 3 cm, bottom rocky, water temperature 11.0˚C, exposed to the sun, elevation 1,853 m, 22˚21���18.609���N/103˚46���27.550���E) slow-flowing in forest, Oguy Ho, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. Biological notes. The pupae of this new species were collected from plastic sheets in the current. Associated species were S. (M.) nigrofilum sp. nov., S. (N.) laichauense sp. nov., S. (N.) tayense sp. nov., S. (S.) rosliramlii sp. nov. and S. (S.) turgidum sp. nov. Distribution. Vietnam (Lao Cai). Etymology. The species name eshimai is in honor of Prof. Nobuoki Eshima, Kyoto University, for his great contribution to statistical analysis of infectious diseases and long-standing support of our studies of black flies. Remarks. This new species is placed in the S. darjeelingense species-group (five species included) of the subgenus Gomphostilbia, defined by Takaoka (2012), based on the fore coxae darkened, male hind basitarsus enlarged (Fig. 23 B), ventral plate not produced ventrally (Fig. 23 E, F) (its ratio of the height against the greatest width is 0.33), and pupal gill with eight short slender filaments (Fig. 24 B). This new species shows great similarities to S. (G.) chayamaritae Takaoka & Srisuka from Thailand (Takaoka and Sris, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 53-60, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Srisuka, W. (2010) Simulium (Gomphostilbia) chayamaritae, a new species of black fly (Diptera: Simuliidae) from northern Thailand. Medical Entomology and Zoology, 61 (2), 265 - 271.","Datta, M. (1973) New species of black flies (Diptera: Simuliidae) of the subgenera Eusimulium Roubaud and Gomphostilbia Enderlein from the Darjeeling area, India. Oriental Insects, 7, 363 - 402.","Chen, H. B., Zhang, C. L. & Yang, M. (2003 a) Checklist of Guizhou blackflies with descriptions of a new species (Diptera: Simuliidae). Guizhou Science, 21, 46 - 50.","Takaoka, H. (2001 b) Two new and three newly recorded species of black flies (Diptera: Simuliidae) from Sabah, Malaysia. Japanese Journal of Tropical Medicine and Hygiene, 29 (2), 221 - 230.","An, J. Y., Zhang, Y. Z. & Deng, C. Y. (1990) Survey of Simuliidae (Diptera) from Xizang, China. Control of blood-sucking dipteran insects, 2, 103 - 109. [text in Chinese with an English abstract]"]}

Simulium (Simulium) taythienense Takaoka, Sofian-Azirun & Ya���cob, 2014 Simulium (Simulium) taythienense Takaoka, Sofian-Azirun & Ya���cob (in Takaoka et al., 2014a): 353���361 (Female, male, pupa and larva). Distribution. Vietnam (Lam Dong and Vinh Phuc). Remark. This species was described from Vinh Phuc Province in northern Vietnam (Takaoka et al. 2014a), and also recorded from Lam Dong Province in southern Vietnam (Takaoka et al. 2015a)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 125, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 a) New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam. Zootaxa, 3838 (3), 347 - 366. https: // doi. org / 10.11646 / zootaxa. 3838.3.6","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

Simulium (Gomphostilbia) hongthaii Takaoka, Sofian-Azirun & Ya���cob, 2014 Simulium (Gomphostilbia) hongthaii Takaoka, Sofian-Azirun & Ya���cob (in Takaoka et al., 2014a): 348��� 351 (Male and pupa). This species was described from males and pupae collected from Tam Dao National Park in northern Vietnam (Takaoka et al. 2014a). The female and larva of this species are here described for the first time. Female. Body length 2.0��� 2.3 mm. Head. Slightly narrower than width of thorax. Frons dark brown, densely covered with yellowish-white scale-like recumbent short hairs interspersed with few dark longer hairs near vertex; frontal ratio 1.6���1.7:1.0:1.9���2.2; frons:head ratio 1.0:4.1���4.2. Fronto-ocular area well developed, narrow, directed dorsolaterally. Clypeus dark brown, densely covered with yellowish-white short hairs interspersed with several dark longer hairs near ventral margin on each side. Labrum 0.65���0.69 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, dark brown except scape, pedicel, and base of first flagellomere yellow. Maxillary palp composed of five segments, light to medium brown except segments 1 and 2 dark yellow, proportional lengths of third, fourth, and fifth segments 1.0:1.1���1.2:2.5���2.6; third segment (Fig. 11 A) widened; sensory vesicle (Fig. 11 A) ellipsoidal (0.3���0.4 times length of third segment), with medium-sized opening. Maxillary lacinia with 8 inner and 12���14 outer teeth. Mandible (Fig. 11 B) with 17���21 inner teeth and lacking outer teeth though outer margin undulate, appearing to have four to six rudimentary teeth. Cibarium (Fig. 11 C) medially forming sclerotized plate folded forward from posterior margin, with moderately sclerotized mediolongitudinal ridge with bifid apex. Thorax. Scutum dark brown to brownish black except anterolateral calli ochreous, and three blackish longitudinal vittae (one median, two submedian) though not clearly demarcated, thinly pruinose and shiny when illuminated at certain angles, densely covered with whitish-yellow to yellow scale-like recumbent short hairs except three longitudinal vittae covered with dark short hairs. Scutellum ochreous, covered with yellow short hairs and dark-brown longer upright hairs along posterior margin. Postnotum dark brown, whitish-gray pruinose and shiny when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, medium to dark brown, shiny when illuminated at certain angles, moderately covered with fine short hairs. Legs. Foreleg: coxa and trochanter whitish yellow; femur light brown with apical cap medium brown (though extreme tip yellowish); tibia white except apical one-fourth dark brown, covered with white fine hairs on basal four-fifths; tarsus brownish black, with moderate dorsal hair crest; basitarsus moderately dilated, 6.6 times as long as its greatest width. Midleg: coxa medium brown except posterolateral surface dark brown; trochanter dark yellow with base whitish yellow; femur dark yellow to light brown with basal half of inner surface yellow and apical cap medium brown (though extreme tip yellowish); tibia light brown except basal two-fifths whitish yellow and apical cap dark brown (and apical three-fifths of posterior surface dark brown), covered with whitish and yellowish fine hairs on posterior and inner surfaces of little more than basal half; tarsus dark brown though basal half or little less of basitarsus yellow. Hind leg: coxa light brown; trochanter whitish yellow; femur light brown with base whitish yellow and apical cap medium brown (though extreme tip yellowish); tibia white or yellowish white on basal twothirds and light brown on rest though apical cap brownish black, covered with whitish fine hairs on outer and posterior surfaces of little more than basal three-fourths; tarsus brownish black except basal two-thirds or little more of basitarsus (though base light brown) and basal half of second tarsomere yellowish white; basitarsus (Fig. 11 D) narrow, nearly parallel-sided though slightly narrowed apically, 7.0 times as long as wide, and 0.6 and 0.6 times as wide as greatest widths of tibia and femur, respectively; calcipala (Fig. 11 D) nearly as long as width at base, and 0.6 times as wide as greatest width of basitarsus; pedisulcus (Fig. 11 D) well developed; claw (Fig. 11 E) with large basal tooth 0.46 times length of claw. Wing. Length 2.2 mm. Costa with dark spinules and hairs except basal patch of hairs yellow. Subcosta with dark hairs except near apex bare. Hair tuft on base of radius yellow. Basal portion of radius fully haired; R1 with dark spinules and hairs; R2 with hairs only. Basal cell absent. Halter. White except basal portion darkened. Abdomen. Basal scale light ochreous, with fringe of whitish-yellow hairs. Dorsal surface of abdomen light to dark brown except segment 2 yellow to light ochreous, moderately covered with dark short to long hairs; tergites of segments 2 and 6���9 shiny when illuminated at certain angles. Ventral surface of segment 2 yellowish white, those of segments 3���5 ochreous and those of other segments medium brown; sternal plate on segment 7 undeveloped. Terminalia. Sternite 8 (Fig. 11 F) bare medially, with 17���22 medium-long to long hairs together with few slender short hairs on each side. Ovipositor valve (Fig. 11 F) triangular (though posteromedial corner rounded), thin, membranous, moderately covered with microsetae interspersed with one to three short hairs; inner margins nearly straight or slightly sinuous, somewhat sclerotized, and moderately separated from each other. Genital fork (Fig. 11 G) of usual inverted-Y form, with slender stem; arms of moderate width, moderately folded medially, without lobe directed posteromedially. Paraproct in ventral view (Fig. 11 H) somewhat concave anterolaterally, with three or four sensilla on anteromedial surface; paraproct in lateral view (Fig. 11 I) slightly produced ventrally beyond ventral tip of cercus, 0.7 times as long as wide, with 17���24 medium-long to long hairs on ventral and lateral surfaces. Cercus in lateral view (Fig. 11 I) short, rounded posteriorly, 0.5 times as long as wide. Spermatheca (Fig. 11 J) ellipsoidal, 1.4 times as long as its greatest width, well sclerotized except duct and small area near juncture with duct unsclerotized, and with many fissures on outer surface; internal setae absent; both accessory ducts slender, subequal in diameter to major one. Mature larva. Body length 5.0 mm. Thorax whitish to light ochreous except anterior portion of first segment, proleg and ventral surface of segments 2 and 3 light gray, with reddish-brown transverse band on dorsal surface of segment 1 (though often disconnected medially); abdominal segments 1���4 entirely grayish, abdominal segments 5��� 9 light gray on dorsal and dorsolateral surfaces, abdominal segments 5 and 6 each with reddish-brown transverse band dorsally, and abdominal segments 7���9 faintly and irregularly mottled with reddish-brown markings dorsally. Head. Head capsule (Fig. 12 A) whitish yellow except surrounding areas of posterior spots of posterolateral spots darkened, and sparsely covered with unpigmented minute setae (though moderately on dorsal surface); all head spots on dorsal, lateral and ventral surfaces distinctively positive except anterior spots of posterolateral spots indistinct and posterior spots of posterolateral spots merged into darkened surrounding areas on cephalic apotome; eyebrow faintly visible. Antenna composed of three articles and apical sensillum, longer than stem of labral fan; proportional lengths of first, second, and third articles 1.0:0.7:0.9. Labral fan with 41 primary rays. Mandible (Fig. 12 C) with three comb-teeth decreasing in length from first tooth to third; mandibular serration composed of two teeth (one medium-sized, one small); major tooth at acute angle against mandible on apical side; supernumerary serrations absent. Hypostoma (Fig. 12 D) with row of nine apical teeth, of which median tooth is longer than each corner tooth; lateral margin smooth; five hypostomal bristles per side lying slightly divergent posteriorly from lateral margin. Postgenal cleft (Fig. 12 B) rounded, medium-long, 1.3 times length of postgenal bridge. Cervical sclerites composed of pair of small light-brown rod-like pieces. Thorax and Abdomen. Thoracic proleg without hairs; thoracic cuticle bare; abdominal cuticle of segments 1���6 sparsely covered with unpigmented minute setae on dorsal and dorsolateral surface, and that of segments 7���9 sparsely to moderately covered with slightly darkened unbranched minute setae interspersed with unbranched colorless setae (Fig. 12 E) on dorsal and dorsolateral surfaces; last abdominal segment densely covered with unbranched colorless longer setae on dorsolateral and lateral surfaces of each side of anal sclerite and on each lateral surface even down to base of ventral papilla; thorax and abdomen without dorsal protuberances. Rectal scales absent. Rectal organ compound, each of three lobes with 11���14 finger-like secondary lobules. Anal sclerite of usual X-form, with anterior arms 1.1 times length of posterior ones, broadly sclerotized at base; no sensilla on broad base and posterior to posterior arms; accessory sclerite absent. Last abdominal segment with pair of large conical ventral papillae. Posterior circlet with 83 rows of hooklets with up to 13 hooklets per row. Specimens examined. Four females, four males and one mature larva collected from a small moderatelyflowing stream (width 1.5 m, depth 10 cm, water temperature 13.0˚C, partially shaded, elevation 1,105 m, 22˚18���48.273���N/103˚53���10.384���E), Sapa, Lao Cai Province, northern Vietnam, 21-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. Distribution. Vietnam (Lam Dong, Lao Cai, Thua Thien Hue and Vinh Phuc). Remarks. The female of S. (G.) hongthaii is similar to that of S. (G.) asakoae originally described from Peninsular Malaysia (Takaoka and Davies 1995) in many characters including the size of the sensory vesicle (Fig. 11 A) and leg colors but is distinguished from the latter by the mandible lacking distinct outer teeth (Fig. 11 B). The larva of this species is distinguished from that of S. (G.) asakoae by the grayish abdominal segments 1���4., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 30-33, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 a) New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam. Zootaxa, 3838 (3), 347 - 366. https: // doi. org / 10.11646 / zootaxa. 3838.3.6","Takaoka, H. & Davies, D. M. (1995) The Black Flies (Diptera: Simuliidae) of West Malaysia. Kyushu University Press, Fukuoka, viii + 175 pp."]}

Simulium (Gomphostilbia) unii Takaoka & Pham sp. nov. Female. Body length 2.0��� 2.5 mm. Head. Slightly narrower than width of thorax. Frons brownish black, densely covered with yellowish-white scale-like recumbent short hairs interspersed with few dark longer hairs near vertex; frontal ratio 1.8:1.0:2.3���2.5; frons:head ratio 1.0:4.6. Fronto-ocular area well developed, narrow, directed dorsolaterally. Clypeus brownish black, densely covered with yellowish-white scale-like hairs interspersed with 10���12 dark longer hairs on each side. Labrum 0.6 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, light to medium brown except scape, pedicel, and basal half of first flagellomere yellow. Maxillary palp composed of five segments, light to medium brown, proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.4���2.5; third segment (Fig. 17 A) widened apically; sensory vesicle (Fig. 17 A) small, ellipsoidal (0.2 times length of third segment), with small opening. Maxillary lacinia with 10���12 inner and 15���17 outer teeth. Mandible (Fig. 17 B) with 28 or 29 inner teeth and one or two outer teeth at some distance from tip. Cibarium (Fig. 17 C) medially forming sclerotized plate folded forward from posterior margin, with moderately sclerotized mediolongitudinal ridge with bifid apex. Thorax. Scutum dark brown except anterolateral calli ochreous, and three blackish longitudinal vittae (one median, two submedian), thinly pruinose and shiny when illuminated at certain angles, densely covered with whitish-yellow to yellow scale-like recumbent short hairs except three longitudinal vittae covered with dark short hairs. Scutellum ochreous, covered with yellow short hairs and dark-brown longer upright hairs along posterior margin. Postnotum dark brown, slightly shiny when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, medium to dark brown, shiny when illuminated at certain angles, moderately covered with fine short hairs. Legs. Foreleg: coxa whitish yellow; trochanter light brown except base whitish yellow; femur light brown with apical cap medium brown (though extreme tip yellowish); tibia white except apical one-fourth dark brown, covered with white fine hairs on basal four-fifths; tarsus brownish black, with moderate dorsal hair crest; basitarsus moderately dilated, 6.4���6.8 times as long as its greatest width. Midleg: coxa yellow with light brown basal portion except posterolateral surface dark brown; trochanter whitish yellow; femur light brown with base yellow (though inner surface of basal half yellow) and apical cap medium brown (though extreme tip yellowish); tibia medium to dark brown except basal one-third whitish yellow (though inner surface of basal two-thirds yellow), covered with whitish and yellowish fine hairs on posterior and inner surfaces of basal two-thirds; tarsus dark brown though basal half or little less of basitarsus yellow. Hind leg: coxa light brown except anterior two-fifths yellow; trochanter whitish yellow; femur light to medium brown with base whitish yellow and apical cap dark brown (though extreme tip yellowish); tibia (Fig. 17 D) yellowish white on basal two-thirds and brownish black on rest, covered with whitish fine hairs on outer and posterior surfaces of little more than basal three-fourths; tarsus brownish black except basal two-thirds or little more of basitarsus (though base light brown) and basal half of second tarsomere yellowish white; basitarsus (Fig. 17 E) narrow, nearly parallel-sided though slightly narrowed apically, 6.0���6.1 times as long as wide, and 0.7 and 0.6 times as wide as greatest widths of tibia and femur, respectively; calcipala (Fig. 17 E) nearly as long as width at base, and 0.5 times as wide as greatest width of basitarsus; pedisulcus (Fig. 17 E) well developed; claw (Fig. 17 F) with large basal tooth 0.5 times length of claw. Wing. Length 2.0��� 2.2 mm. Costa with dark spinules and hairs except basal patch of hairs yellow. Subcosta with dark hairs except near apex bare. Hair tuft on base of radius yellow. Basal portion of radius fully haired; R1 with dark spinules and hairs; R2 with hairs only. Basal cell absent. Halter. White except basal portion darkened. Abdomen. Basal scale yellow, with fringe of whitish-yellow hairs. Dorsal surface of abdomen light to dark brown except anterior two-thirds of segment 2 whitish, moderately covered with dark short to long hairs; tergites of segments 2 and 6���9 shiny when illuminated at certain angles. Ventral surface of segment 2 yellowish white, that of segment 3 dark yellow and those of other segments medium brown; sternal plate on segment 7 undeveloped. Terminalia. Sternite 8 (Fig. 17 G) bare medially, with 17���28 medium-long to long hairs together with two to four slender short hairs on each side. Ovipositor valve (Fig. 17 G) triangular (though posteromedial corner rounded), thin, membranous, moderately covered with microsetae interspersed with two short hairs; inner margins nearly straight or slightly sinuous, somewhat sclerotized, and moderately separated from each other. Genital fork (Fig. 17 H) of usual inverted-Y form, with slender stem; arms of moderate width, moderately folded medially, without lobe directed posteromedially. Paraproct in ventral view (Fig. 17 I) somewhat concave anterolaterally, with three to six sensilla on anteromedial surface; paraproct in lateral view (Fig. 17 J) slightly produced ventrally beyond ventral tip of cercus, 0.7 times as long as wide, with 25���30 medium-long to long hairs on ventral and lateral surfaces. Cercus in lateral view (Fig. 17 J) short, rounded posteriorly, 0.5 times as long as wide. Spermatheca (Fig. 17 K) ellipsoidal, 1.2���1.5 times as long as its greatest width, well sclerotized except duct and small area near juncture with duct unsclerotized, and with many fissures on outer surface; internal setae absent; both accessory ducts slender, subequal in diameter to major one. Male. Body length 2.1���2.4 mm. Head. Somewhat wider than thorax. Upper eye medium brown, consisting of 13 or 14 vertical columns and 14 horizontal rows of large facets. Face brownish black, white pruinose. Clypeus brownish black, whitish pruinose, densely covered with golden-yellow scale-like medium-long hairs (mostly directed upward) interspersed with several dark-brown unbranched longer hairs. Antenna composed of scape, pedicel and nine flagellomeres, yellowish except flagellomeres 5���9 or 6���9 light to medium brown; first flagellomere elongate, 1.8 times length of second one. Maxillary palp light to medium brown, with five segments, proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.2; third segment (Fig. 18 A, B) slender; sensory vesicle (Fig. 18 A, B) small, globular or ellipsoidal (0.1 times length of third segment), and with small opening. Thorax. Scutum dark brown, without longitudinal vittae, shiny and thinly gray pruinose on shoulders, on wide area along each lateral margin and on prescutellar area when illuminated at certain angles, and densely covered with golden-yellow scale-like recumbent short hairs. Scutellum medium brown, covered with yellow short hairs and dark-brown long upright hairs along posterior margin. Postnotum dark brown, slightly shiny and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum medium brown, longer than deep, shiny when illuminated at certain angles, moderately covered with fine short hairs. Legs. Foreleg: coxa whitish yellow; trochanter light brown with base whitish yellow; femur light brown with apical cap medium brown (though apical tip yellowish); tibia yellow except basal one-third light brown and apical one-third medium brown, and covered with yellow hairs on basal two-thirds of outer surface; tarsus brownish black; basitarsus moderately dilated, 7.6���7.8 times as long as its greatest width. Midleg: coxa light brown except posterior surface dark brown; trochanter yellowish; femur light brown with base yellowish and apical cap medium brown (though apical tip yellow); tibia medium brown except basal one-third yellowish; tarsus dark brown except basal half of basitarsus yellow (border not well defined). Hind leg: coxa light brown though apical portion yellow; trochanter yellow; femur light to medium brown with base narrowly yellow and apical cap dark brown (though apical tip whitish yellow); tibia (Fig. 18 C) medium to dark brown except little less than basal half whitish yellow and apex brownish black, covered with yellow hairs on basal three-fourths of outer and posterior surface; tarsus (Fig. 18 D) medium to dark brown except basal half or little more of basitarsus and basal half of second tarsomere whitish yellow; basitarsus (Fig. 18 D) enlarged, spindle-shaped, 4.3���4.6 times as long as wide, and 0.8���0.9 and 0.8 times as wide as greatest width of tibia and femur, respectively; calcipala (Fig. 18 D) nearly as long as basal width, and 0.4 times as wide as greatest width of basitarsus. Pedisulcus (Fig. 18 D) well developed. Wing. Length 1.9���2.0 mm. Other characters as in female except subcosta bare. Halter. Grayish white except basal stem darkened and apical half grayish ochreous. Abdomen. Basal scale medium brown, with fringe of light-brown hairs. Dorsal surface of abdomen dark brown to brownish black except anterior one-third of segment 2 yellowish, covered with dark-brown short to long hairs; segments 2 and 5���8 each with pair of shiny dorsolateral or lateral patches; ventral surface of segments 2 and 3 whitish though sternal plate of segment 3 darkened, and those of other segments medium to dark brown. Genitalia. Coxite in ventral view (Fig. 18 E) nearly rectangular, 1.9 times as long as its greatest width. Style in ventral view (Fig. 18 E) bent inward, with blunt apex having single spine; style in ventrolateral view (Fig. 18 F) slightly tapered toward apex, with truncated apex. Ventral plate in ventral view (Fig. 18 E) with body transverse, 0.6 times as long as wide, with anterior margin produced anteromedially, and posterior margin somewhat concave medially (though posterior margin slightly convex medially when ventral plate is slightly tilted), slightly narrowed medially, then nearly parallel-sided, and densely covered with microsetae on ventral surface; basal arms of moderate length, directed forward; ventral plate in lateral view (Fig. 18 G) moderately produced ventrally; ventral plate in caudal view (Fig. 18 H) gently rounded ventrally, densely covered with microsetae on posterior surface. Median sclerite (Fig. 18 I) plate-like and wide. Parameres (Fig. 18 J) of moderate size, each with four distinct long and medium-long stout hooks, and without minute setae on outer surface of basal arm. Aedeagal membrane (Fig. 18 J) moderately setose; dorsal plate not defined. Ventral surface of abdominal segment 10 (Fig. 18 K, L) without distinct hairs near posterior margin. Cercus (Fig. 18 K, L) small, rounded, with 14���16 hairs. Pupa. Body length 2.4���2.5 mm. As in S. (G.) sanchayense sp. nov. except following characters. Thorax. Gill (Fig. 19 A, B, C) composed of eight slender thread-like filaments, arranged as [(2+1)+(2+1)]+2, or [3+(2+1)]+2, or [(2+1)+3]+2, or (3+3)+2 from dorsal to ventral, with short common basal stalk having somewhat swollen basal fenestra ventrally at base; common basal stalk 0.6���0.8 times length of interspiracular trunk; dorsal and middle triplets sharing short stalk 0.6���0.9 times length of common basal stalk; dorsal and middle triplets each composed of one individual filament and two paired filaments with short primary and secondary stalks (secondary stalk usually much shorter than primary stalk but in left gill of one pupa secondary stalk is exceptionally long, twice length of primary stalk as shown in Fig. 19 C), or three filaments arising at same level from primary stalk; ventral paired filaments with medium-long stalk 0.9���1.5 times length of common basal stalk; primary stalk of dorsal triplet lying against that of ventral pair at angle of 90 degrees or little greater when viewed laterally; all filaments medium brown, gradually tapered toward apex; three filaments of dorsal triplet subequal in length (2.3���2.5 mm long including their own stalks and common basal stalk) and thickness to one another; three filaments of middle triplet subequal in length (2.6���3.0 mm) and thickness; inner filament of ventral pair longest (2.8���3.2 mm), slightly longer than outer filament (2.7���3.1 mm); two filaments of ventral pair subequal in thickness to each other, and 1.2���1.5 times as thick as six other filaments when compared basally; cuticle of all filaments with well-defined annular ridges and furrows, and densely covered with minute tubercles. Abdomen. Dorsally, segments 1, 2 and 9 yellow, and other segments whitish yellow at least medially; segment 9 with pair of flat triangular terminal hooks, of which outer margin 1.8 times length of inner margin and crenulated (Fig. 19 D). Cocoon (Fig. 19 E, F). Wall-pocketshaped, moderately woven, widely extended ventrolaterally; anterior margin thickly woven medially, with dorsomedial projection, resembling letter W when viewed dorsally; posterior three-fifths with floor roughly woven; individual threads visible; 3.0��� 3.9 mm long by 2.0��� 2.9 mm wide. Mature larva. Body length 4.4���5.5 mm. Body whitish to light ochreous, with following color markings: thoracic segment 1 encircled with reddish-brown band (though often disconnected ventromedially), proleg light ochreous, thoracic segments 2 and 3 reddish brown on ventral surface, though lighter on segment 3; abdominal segments 1 and 2 each encircled by grayish broad band; abdominal segments 3 and 4 each with or without pair of narrow light reddish-brown dorsolateral spots; abdominal segment 5 encircled by distinct reddish-brown transverse band though disconnected ventromedially, abdominal segment 6 with similar colored transverse band (though much narrower) on dorsal and dorsolateral surfaces, though often faded to varying extent leaving reddish-brown round spot dorsomedially, and pair of light reddish-brown spots ventrally; abdominal segments 7 and 8 widely reddish brown on dorsal and dorsolateral surfaces, though faded to varying extent anteromedially; abdominal segment 7 with reddish-brown narrow transverse band ventrally. Head. Head capsule whitish yellow, sparsely covered with minute setae (though moderately on dorsal surface); head spots faintly positive though two relatively large spots near posterior margin on lateral surface usually moderately positive, and two small spots below eyespot region often indistinct; eyebrow indistinct. Antenna composed of three articles and apical sensillum, longer than stem of labral fan; proportional lengths of first, second, and third articles 1.0:0.6���0.8:0.9. Labral fan with 36��� 41 primary rays. Mandible (Fig. 20 A) with three comb-teeth decreasing in length from first tooth to third; mandibular serration composed of two teeth (one medium-sized, one small); major tooth at acute angle against mandible on apical side; supernumerary serrations absent. Hypostoma (Fig. 20 B) with row of nine apical teeth, of which median tooth is longer than each corner tooth; lateral margin smooth; four or five hypostomal bristles per side lying slightly divergent posteriorly from lateral margin. Postgenal cleft (Fig. 20 C) rounded, medium-long, 1.4 times length of postgenal bridge. Cervical sclerites composed of pair of small unpigmented rod-like pieces. Thorax and Abdomen. Thoracic proleg without hairs; thoracic cuticle almost bare; abdominal cuticle of segments 1���6 almost bare, and that of segments 5���9 sparsely covered with slightly darkened unbranched or bifid or trifid minute setae (Fig. 20 D) on dorsal and dorsolateral surfaces; last abdominal segment densely covered with unbranched colorless longer setae on dorsolateral and lateral surfaces of each side of anal sclerite and on each lateral surface even down to base of ventral papilla; thorax and abdomen without dorsal protuberances. Rectal scales absent. Rectal organ compound, each of three lobes with six to nine finger-like secondary lobules. Anal sclerite of usual Xform, with anterior arms nearly as long as posterior ones, broadly sclerotized at base; no sensilla on broad base and posterior to posterior arms; accessory sclerite absent. Last abdominal segment with pair of large conical ventral papillae. Posterior circlet with 68 rows of hooklets with up to 12 hooklets per row. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 28, Holotype, Simulium (G.) unii , Female, coll. Vietnam, 11-XII-2015, Takaoka et al.], reared from a pupa collected from a slow-flowing stream (width 1.0 m, depth 5���10 cm, bottom sandy, water temperature 18.0˚C, shaded, elevation 80 m, 19˚30���46.589���N/105˚09���10.470���E), Chau Dinh, Quy Chau, Nghe An Province, northern Vietnam, 11-XII-2015, by H. Takaoka, M. Sofian-Azirun, C.D. Chen & K.W. Lau. PARATYPES: Six females, three males and two mature larvae, same data as those of holotype, labeled in each vial as [UMSRP: Vietnam 0 28, Paratype, Simulium (G.) unii , coll. Vietnam, 11-XII-2015, Takaoka et al.]. Biological notes. The pupae and larvae of this new species were collected from fallen leaves and grasses tailing in the current. Associated species were S. (G.) chaudinhense sp. nov., S. (G.) parahiyangum, S. (S.) nodosum and S. (S.) tani (complex). Etymology. The species name unii is in honor of Prof. Sigehiko Uni, Institute of Biological Sciences, Faculty of Science, University of Malaya, for his great contribution to taxonomic studies of filariae of wild animals in relation to zoonotic onchocerciasis in Japan. Distribution. Vietnam (Nghe An). Remarks. Simulium (G.) unii sp. nov. is placed in the S. asakoae species-group by having the yellow hair tuft on the base of the radius and enlarged male hind basitarsus (Fig. 18 D), although the ventral plate of this new species is not clearly emarginated on each lateral margin (Fig. 18 E), a character disagreeing with one of the key characters of this species-group defined by Takaoka (2012). This new species is characterized by the cocoon having an anterodorsal projection (Fig. 19 E). Among the 25 species of the S. asakoae species-group (Takaoka 2012; Takaoka et al. 2014a, d, 2015a), S. (G.) gyorkosae Takaoka & Davies from Java, Indonesia (Takaoka and Davies 1996); S. (G.) fanjingshanense Chen, Zhang & Wen from Guizhou, south China (Chen et al. 2000); S. (G.) fuscidorsum Takaoka & Ya���cob from Vietnam (Takaoka et al. 2015a); S. (G.) phulocense Takaoka & Chen from Vietnam (Takaoka et al. 2015a); and S. (G.) yunnanense Chen & Zhang from Yunnan, China (Chen and Zhang 2004) have a similar cocoon. However, S. (G.) unii sp. nov. is distinguished from these five known species by the following characters (those of, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 42-49, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 a) New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam. Zootaxa, 3838 (3), 347 - 366. https: // doi. org / 10.11646 / zootaxa. 3838.3.6","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z. & Hashim, R. (2014 d) Two new species of Simulium (Gomphostilbia) (Diptera: Simuliidae) from Cameron's Highlands, Peninsular Malaysia, with keys to 21 species of the Simulium asakoae speciesgroup. Zootaxa, 3765 (1), 54 - 68.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96.","Takaoka, H. & Davies, D. M. (1996) The Black Flies (Diptera: Simuliidae) of Java, Indonesia. Bishop Museum Bulletin in Entomology 6. Bishop Museum Press, Honolulu, Hawaii, viii + 81 pp.","Chen, H. B., Zhang, J. Q. & Wen, X. J. (2000) Two new species of Simulium (Gomphostilbia) from Fanjing Mountain, China (Diptera, Simuliidae). Entomologica Sinica, 7, 21 - 28."]}

Simulium (Simulium) laui Takaoka & Sofian-Azirun, 2015 Simulium (Simulium) laui Takaoka & Sofian-Azirun, 2015 (in Takaoka et al., 2015a): 67���74 (Female, male, pupa and larva). Distribution. Vietnam (Lam Dong). Remarks. Simulium (S.) laui was described from Lam Dong Province, Vietnam (Takaoka et al. 2015a). This species is similar to S. (S.) lacduongense although it is distinguished from the latter by the bare basal portion of the female radial vein (Takaoka et al. 2015a)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 116, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

Simulium (Gomphostilbia) siamense Takaoka & Suzuki, 1984 Simulium (Gomphostilbia) siamense Takaoka & Suzuki, 1984: 14 –18 (Female, male, pupa and larva). Distribution. Thailand and Vietnam. Remarks. This species was described from Thailand by Takaoka and Suzuki (1984), and later recorded from Vietnam by Crosskey and Howard (1997). No detailed information of this record was given, leaving the locality in Vietnam unknown. There is a possibility that the taxa regarded as S. (G.) siamense and S. (G.) duolongum are the same species because the pupal gills of both species are morphologically indistinguishable from each other (Takaoka and Suzuki 1984; Takaoka and Davies 1995).

3) Simulium vernum species-group Simulium (Nevermannia) laichauense Takaoka & Sofian-Azirun sp. nov. Female. Body length 2.5 mm. Head. Slightly narrower than width of thorax. Frons brownish black, moderately covered with whitish yellow (golden yellow when illuminated at certain angles) recumbent short hairs interspersed with few dark-brown long hairs along each lateral margin; frontal ratio 1.8:1.0:2.6. Frons:head ratio 1.0:5.9. Fronto-ocular area directed laterally and slightly upward, rounded apically. Clypeus dark brown, thinly whitishgray pruinose, slightly shiny when illuminated at certain angles, moderately covered with yellow short hairs interspersed with one to three dark-brown long hairs though mediolongitudinal area widely bare. Labrum 0.7 times as long as clypeus. Antenna composed of scape, pedicel and nine flagellomeres, entirely brownish black; first flagellomere 1.6 times as long as second one. Maxillary palp composed of five segments, medium brown except segments 1 and 2 ochreous and segment 3 dark brown, proportional lengths of third, fourth, and fifth segments 1.0:0.8:1.5; third segment (Fig. 28 A) somewhat enlarged; sensory vesicle (Fig. 28 A) enlarged, ellipsoidal, 0.5 times as long as third segment, and with large opening apically. Maxillary lacinia with 15 inner and 17 or 18 outer teeth. Mandible with 35 inner and 17 or 18 outer teeth. Cibarium (Fig. 28 B) with enlarged cornuae; no processes near anterodorsal surface. Thorax. Scutum black except anterolateral calli dark brown, thinly whitish-gray pruinose and slightly shiny when illuminated at certain angles, densely covered with whitish yellow (golden yellow when illuminated at certain angles) recumbent short hairs. Scutellum dark brown, covered with whitish-yellow short hairs and dark-brown long hairs. Postnotum brownish black, whitish-gray pruinose and slightly shiny when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, brownish black, whitish-gray pruinose and slightly shiny when illuminated at certain angles, and bare. Legs. Medium to dark brown except basal extreme of hind tibia and narrow portion of pedisulcus of second tarsomere pale. Fore basitarsus somewhat dilated, 8.7 times as long as its greatest width. Hind basitarsus (Fig. 28 C) slender, nearly parallel-sided, 7.8 times as long as wide, and 0.7 and 0.6 times as wide as tibia and femur, respectively; calcipala (Fig. 28 C) well developed, slightly longer than basal width, and 0.5 times as wide as greatest width of basitarsus; pedisulcus (Fig. 28 C) well developed; claw (Fig. 28 D) with large basal tooth 0.5 times length of claw. Wing. Length 2.9 mm. Costa with dark-brown spinules and hairs except basal patch of hairs yellowish white. Subcosta with dark-brown hairs except apical one-fifth or one-fourth bare. Hair tuft on base of radius dark brown. Basal portion of radius fully haired. R1 with dark-brown spinules and hairs. R2 with dark-brown hairs only. Basal cell and basal median cell absent. Halter. White except basal stem darkened. Abdomen. Basal scale ochreous to light brown, with fringe of yellowish-white long hairs; dorsal surface of abdomen medium brown except rest of tergal plate of segment 2 ochreous, and moderately covered with whitish-yellow short hairs as well as dark-brown short to medium-long hairs; tergites 6���8 shiny when illuminated at certain angles; ventral surface of segments 2���7 light ochreous, and segment 8 medium brown; segment 7 with weakly defined large sternal plate medially. Terminalia. Sternite 8 (Fig. 28 E) bare medially, and with 10���14 short to long hairs on each side. Ovipositor valve (Fig. 28 E) triangular, rounded posteromedially, thin, membranous, densely covered with microsetae interspersed with four to six fine short setae (though one seta on each side medium-long); inner margins moderately sclerotized, narrowly darkened, slightly sinuous, and moderately separated from each other. Genital fork (Fig. 28 F) of usual inverted-Y form, stem slender and moderately sclerotized; arms each with broad lateral plate having strongly sclerotized lateral margin. Paraproct in ventral view (Fig. 28 G) ovoidal, with strongly sclerotized anterior surface, covered with 10 mediumlong and long hairs on ventral and lateral surfaces, with shallow depression along anteromedial margin, with four or seven sensilla on anteromedial transparent surface; paraproct in lateral view (Fig. 28 H) slightly produced ventrally beyond ventral margin of cercus. Cercus in ventral view (Fig. 28 G) narrow, with widely concave inner surface; cercus in lateral view (Fig. 28 H) rounded posteriorly, 0.6 times as long as wide, and with numerous medium-long to long hairs. Spermatheca (Fig. 28 I) small, ovoidal, 1.2 times as long as its greatest width, well sclerotized except area at juncture with duct, with reticulate surface pattern; internal setae absent; main duct and both accessory ducts subequal in diameter to one another. Pupa. Body length (excluding gill filaments) 3.4 mm. Head. Integument including antennal sheath yellow except frons dark brown (Fig. 29 A), and bare; frons with three unbranched long trichomes with straight apices (Fig. 29 A) arising close together with one another on each side; face with one unbranched long trichome with straight apex (Fig. 29 A) on each side. Thorax. Integument yellow except anterolateral portion widely dark brown, and bare except posterodorsal surface sparsely covered with small tubercles (Fig. 29 B); thorax with three long anterodorsal trichomes with coiled or straight apices, two long anterolateral trichomes with straight apices (one slightly shorter than other), one medium-long mediolateral trichome with straight apex, and three ventrolateral trichomes with straight apices (two long, one medium-long) (Fig. 29 B), on each side; all trichomes unbranched. Gill (Fig. 29 C) with four slender thread-like filaments, arranged in dorsal and ventral pairs, each with short stalk arising from short common basal stalk with moderate basal fenestra at base; common basal stalk 0.54 times length of interspiracular trunk; stalks of dorsal and ventral pair subequal in length and thickness to each other, 0.4���0.5 times length of common basal stalk; common basal stalk directed forward and somewhat outward, stalk of dorsal pair directed upward and forward, with upper filament directed upward and forward, then curved downward, and lower filament directed forward; stalk of ventral pair directed somewhat outward and forward, with outer and inner filaments directed forward; upper filament of dorsal pair and outer filament of ventral pair on each side subequal in length (2.6 mm) to each other, lower filament of dorsal pair and inner filament of ventral pair on each side broken losing apical half, thus not measurable; upper filament of dorsal pair as thick as or very slightly thicker than outer filament of ventral pair; lower filament of dorsal pair and inner filament of ventral pair subequal in thickness to each other, and 0.9 times as thick as counter filament of each pair when compared basally; upper filament of dorsal pair and outer filament of ventral pair slightly tapered toward apices, each with relatively thick apical portion (0.6 times as thick as basal portion); all filaments medium brown, with annular ridges and furrows forming reticulate patterns on surface of basal half, and densely covered with minute tubercles on outer surface. Abdomen. Dorsally, segments 1 and 2 dark gray and with minute spine-like tubercles, basal half of segment 3 grayish, and other segments unpigmented except basal portions of spine-combs on segments 6���9 yellowish and posterior half of segment 9 light grayish; segment 1 with one medium-long hair-like seta on each side; segment 2 with one medium-long hair-like seta and five spinous short setae on each side; segments 3 and 4 each with four dark stout hooked spines and one short spinous seta along posterior margin on each side; segments 2���4 each with one minute seta near anterior margin on each side; segments 5���9 each with comb-like groups of minute spines in transverse rows on each side; segments 6���9 each with spine-combs in transverse row on each side (though those on segment 9 much smaller in size than those on other segments); segment 9 with pair of short blunt terminal hooks (Fig. 29 D, E). Ventrally, all segments unpigmented except segment 9 yellowish gray; segment 4 with one bifid hook and few unbranched short setae on each side; segment 5 with two bifid hooks and few unbranched short setae on each side; segments 6 and 7 each with one bifid or trifid inner hook and one bifid outer hook and few unbranched short setae on each side; segments 4���8 each with comb-like groups of minute spines; all hooks on segments 4���8 each with several minute spines near its base (Fig. 29 F). Cocoon (Fig. 29 G). Wall-pocket-shaped, moderately woven, anterior margin thickly woven, and extended ventrolaterally, without projection; floor woven on posterior two-thirds; individual threads visible; 3.8 mm long by 3.1 mm wide. Male and Mature larva. Unknown. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 32, Holotype, Simulium (N.) laichauense, Female, coll. Vietnam, 20-XII-2014, Takaoka et al.], reared from a pupa collected from a river (width 6 m, depth 0.6 m, bottom rocky, water temperature 11.0˚C, exposed to the sun, elevation 1,728 m, 22˚22���22.719���N/103˚45���24.852���E) fast-flowing near a forest, Lai Chau, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. Biological notes. The pupa of this new species was collected from a grass leaf trailing in the current. Associated species were S. (N.) tayense sp. nov. and S. (S.) giayense sp. nov. Distribution. Vietnam (Lao Cai). Etymology. The species name laichauense refers to the locality name, Lai Chau, where this new species was collected. Remarks. This new species is assigned to the S. vernum species-group of the subgenus Nevermannia, defined by Crosskey (1969), judging from the female terminalia (Fig. 28 E���H) and pupal gill with four long slender filaments (Fig. 29 C). The pupa of this new species is remarkable in having a darkened frons and anterolateral surface of the thorax (Fig. 29 A, B), by which it is distinguished from other members of the S. vernum speciesgroup. Simulium (Nevermannia) tayense Takaoka & Ya���cob sp. nov. Female. Body length 2.8 mm. Head. Slightly narrower than width of thorax. Frons brownish black, gray pruinose, not shiny, densely covered with whitish-yellow scale-like recumbent short hairs interspersed with few dark longer hairs along each lateral margin; frontal ratio 1.7:1.0:2.4; frons:head ratio 1.0:4.9. Fronto-ocular area well developed, narrow, directed dorsolaterally. Clypeus dark brown, gray pruinose, moderately covered with whitishyellow hairs interspersed with few dark longer hairs on each side, though upper and lower portions bare. Labrum 0.9 times as long as clypeus. Antenna composed of scape, pedicel and nine flagellomeres, brownish black except scape and pedicel medium brown. Maxillary palp composed of five segments, light to medium brown except anterior surface of segments 1 and 2 yellowish and third segment dark brown, proportional lengths of third, fourth, and fifth segments 1.0:0.8:1.5; third segment (Fig. 30 A) swollen; sensory vesicle (Fig. 30 A) elongate (0.6���0.7 times as long as third segment), with medium-sized opening. Maxillary lacinia with 13 or 14 inner and 15 or 16 outer teeth. Mandible with 32���34 inner and 14 or 15 outer teeth. Cibarium (Fig. 30 B) without any processes. Thorax. Scutum brownish black except anterolateral calli medium brown, densely covered with yellow scale-like recumbent hairs interspersed with several dark-brown long upright hairs on prescutellar area. Scutellum medium brown, moderately covered with yellow short hairs mixed with several dark-brown long upright hairs. Postnotum dark brown, and bare. Pleural membrane bare. Katepisternum dark brown to brownish black, longer than deep, whitish-gray pruinose, slightly shiny when illuminated at certain angles, and bare. Legs. Foreleg: coxa and trochanter light brown; femur dark yellow to light brown except apical cap dark brown; tibia dark brown, with median large portion on outer surface light brown; tarsus dark brown, with moderate dorsal hair crest; basitarsus moderately dilated, 8.2 times as long as its greatest width. Midleg: as in foreleg except coxa medium brown on anterolateral surface and dark brown on posterolateral surface, and trochanter medium brown. Hind leg: coxa and trochanter medium brown; femur dark yellow to light brown with apical cap medium brown; tibia medium to dark brown except medial large portion on outer surface light to medium brown; tarsus dark brown except basitarsus light to medium brown (though base dark brown) and basal half of second tarsomere light brown; basitarsus (Fig. 30 C) narrow, nearly parallel-sided, 7.1 times as long as wide, and 0.8 and 0.7 times as wide as greatest widths of tibia and femur, respectively; calcipala (Fig. 30 C) nearly as long as width at base, and 0.5 times as wide as greatest width of basitarsus; pedisulcus (Fig. 30 C) shallow; claw (Fig. 30 D) with large basal tooth 0.48 times as long as claw. Wing. Length 3.0 mm. Costa with dark-brown spinules and light-brown hairs though intermixed with yellowish hairs basally. Subcosta with light-brown hairs except apical one-fourth bare. Hair tuft on base of radius dark brown. Basal portion of radius fully haired; R1 with dark spinules and hairs; R2 with hairs only. Basal cell absent. Halter. White except basal stem darkened. Abdomen. Basal scale light brown, with fringe of whitishyellow hairs. Dorsal surface of abdomen dark brown except segment 2 light brown, and tergites 7���9 medium brown, moderately covered with dark short to long hairs intermixed with yellow short hairs; tergites of segments 2 and 7���9 wide and shiny when illuminated at certain angles, tergites 3���6 relatively narrow and dull. Ventral surface of abdomen mostly ochreous to medium brown except segment 2 whitish; sternal plate on segment 7 developed medially. Terminalia. Sternite 8 (Fig. 30 E) bare medially, with 11 medium-long to long yellow hairs together with few slender short yellow hairs on each side. Ovipositor valve (Fig. 30 E) triangular (though medioposterior corner rounded), thin, membranous, moderately covered with microsetae interspersed with four short slender yellow hairs; inner margins slightly concave medially, somewhat sclerotized, and somewhat separated from each other. Genital fork (Fig. 30 F) of usual inverted-Y form, with slender stem; arms of moderate width medially; lateral plate of each arm strongly sclerotized along dorsolateral margin, and with thin lobe directed medioposteriorly. Paraproct in ventral view (Fig. 30 G) nearly quadrate with triangular projection directed medially, with six sensilla on unpigmented anteromedial surface; paraproct in lateral view (Fig. 30 H) somewhat produced ventrally, 0.7 times as long as wide, with 12 or 13 medium-long to long hairs on ventral and lateral surfaces. Cercus in lateral view (Fig. 30 H) short, with truncate posterior margin, 0.7 times as long as wide; cercus in end view much curved outward. Spermatheca (Fig. 30 I) ovoidal, 1.2 times as long as its greatest width, well sclerotized except duct and small area near juncture with duct unsclerotized, and with hexagonal patterns (though not well defined) on surface; internal setae absent; both accessory ducts slender, subequal in diameter to major one. Male. Body length 3.2 mm. Head. Wider than thorax. Upper eye medium brown, with large facets in 17 vertical columns and 19 horizontal rows. Face dark brown, whitish-gray pruinose. Clypeus brownish black, whitish-gray pruinose, moderately covered with golden-yellow medium-long hairs (mostly directed upward). Antenna composed of scape, pedicel and nine flagellomeres, dark brown except extreme base of first flagellomere light brown; first flagellomere elongate, 1.9 times as long as second one. Maxillary palp composed of five segments, light brown except segments 1 and 2 yellow; proportional lengths of third, fourth, and fifth segments 1.0:0.9:1.8; third segment (Fig. 31 A) not swollen; sensory vesicle (Fig. 31 A) ellipsoidal, small, 0.2 times as long as third segment, and with small opening. Thorax. Scutum black, densely covered with golden-yellow recumbent short hairs interspersed with several medium-brown upright long hairs on prescutellar area; other features as in female. Legs. Color nearly as in female except fore trochanter medium brown except inner surface yellow, hind trochanter yellowish except anterior surface medium brown, hind femur yellowish on inner surface. Fore basitarsus slightly dilated, 10.4 times as long as its greatest width. Hind basitarsus (Fig. 31 B) enlarged, spindle-shaped, 3.8 times as long as wide, and 1.1 and 1.2 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 31 B) slightly shorter than basal width, and 0.3 times as wide as greatest width of basitarsus. Pedisulcus (Fig. 31 B) well developed. Wing. Length 2.9 mm; other features as in female except subcosta with few hairs. Halter. White except basal stem darkened. Abdomen. Basal scale dark brown, with fringe of dark long hairs. Dorsal surface of abdomen medium brown except little less than basal half of segment 2 ochreous, moderately covered with yellow short hairs intermixed with dark brown short to medium-long hairs; segments 7 and 8 each with pair of slightly shiny lateral patches when illuminated at certain angles; ventral surface of segment 2 white, those of segments 3���6 ochreous except sternites medium brown, and those of other segments medium brown. Genitalia. Coxite in ventral view (Fig. 31 C) nearly rectangular, twice as long as its greatest width. Style in ventral view (Fig. 31 C) bent inward, nearly parallel-sided, with truncated apex having apical spine; style in ventrolateral view (Fig. 31 D) shorter than coxite (0.8 times as long as coxite), straight up to apical one-third, then curved inwardly, widest at base, nearly parallel-sided up to apical one-third, then gradually narrowed toward apex and with rounded apex; style in medial view (Fig. 31 E) boot-shaped, with triangular apical lobe directed dorsomedially; style in caudal view (Fig. 31 F) widely depressed on posterodorsal surface of medially-directed apical lobe. Ventral plate in ventral view (Fig. 31 C) with subquadrate body, 0.7 times as long as wide, with anterior margin undulate with median concavity, both sides nearly straight though posterolateral corners rounded, and posterior margin with two small and shallow concavities submedially; body of ventral plate darkened along anterior margin, and nearly bare except posteromedian portion of ventral surface densely covered with microsetae; basal arms of moderate length, well sclerotized, divergent from base as shown in Fig. 31 C; ventral plate in lateral view (Fig. 31 G) with body slightly narrowed posteriorly; ventral pla, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 68-79, DOI: 10.5281/zenodo.571608, {"references":["Crosskey, R. W. (1969) A Re-classification of the Simuliidae (Diptera) in Africa and Its Islands. In: Bulletin of the British Museum Natural History. Entomology. Supplement 14. United States Department of Agriculture, London, pp. 1 - 194 pp.","Takaoka, H. (1983) The Blackflies (Diptera: Simuliidae) of the Philippines. Japan Society For The Promotion of Science, Tokyo, xi + 199 pp.","Takaoka, H. & Davies, D. M. (1995) The Black Flies (Diptera: Simuliidae) of West Malaysia. Kyushu University Press, Fukuoka, viii + 175 pp.","Takaoka, H., Srisuka, W., Saeung, A., Otsuka, Y. & Choochote, W. (2012 c) Simulium (Nevermannia) chomthongense, a new species of black fly (Diptera: Simuliidae) from Chiang Mai, Thailand. Tropical Biomedicine, 29, 381 - 390.","Takaoka, H., Srisuka, W., Saeung, A., Otsuka, Y. & Choochote, W. (2013) Simulium (Nevermannia) khunklangense, a new species of black fly (Diptera: Simuliidae) from Chiang Mai, Thailand. Zootaxa, 3694 (3), 280 - 288. https: // doi. org / 10.11646 / zootaxa. 3694.3.8","Chen, H. B., Zhang, C. L. & Huang, L. (2005) A new species of Simulium (Nevermannia) from Sichuan Province, China (Diptera, Simuliidae). Acta Zootaxonomica Sinica, 30, 625 - 627."]}

Simulium (Simulium) congi Takaoka & Sofian-Azirun, 2015 Simulium (Simulium) congi Takaoka & Sofian-Azirun (in Takaoka et al., 2015a): 80���84 (Male, pupa and larva). Distribution. Vietnam (Lam Dong). Remarks. This species was described from one male reared from a pupa, one pharate male and one mature larva collected from Lam Dong Province, southern Vietnam (Takaoka et al. 2015a). The female of this species remains to be collected., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 126, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

Simulium (Simulium) nodosum Puri, 1933 Simulium (Simulium) nodosum Puri. 1933b: 813 ���817 (Female, pupa and larva); Lewis, 1974: 34 ���37 (Female, male, pupa and larva). Specimens examined. Two males (reared from pupae) and five mature larvae, collected from a slow-flowing stream (width 1.5���3.0 m, depth 10���15 cm, bottom sandy, water temperature 18.0˚C, exposed to the sun, elevation 73 m, 19˚30���45.497���N/105˚09���09.261���E), Chau Dinh, Quy Chau, Nghe An Province, northern Vietnam, 11-XII- 2015, by H. Takaoka, M. Sofian-Azirun, C.D. Chen & K.W. Lau. Distribution. India, Thailand, Taiwan, South China, Vietnam (Ha Tay, Hoa Binh, Vinh Phuc, Lam Dong and Nghe An). Remarks. Simulium (S.) nodosum was originally described by Puri (1933b) and redescribed by Lewis (1974). It was recorded from Vietnam by Crosskey and Howard (1997) and Pham (1998). The females of this species were reported to be a human-biter and to transmit an Onchocerca species in Thailand (Takaoka et al. 2003)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 117, DOI: 10.5281/zenodo.571608, {"references":["Puri, I. M. (1933 b) Studies on Indian Simuliidae. Part VII. Descriptions of larva, pupa and female of Simulium nodosum sp. nov. with an appendix dealing with S. novolineatum nov. nom. (= S. lineatum Puri). Indian Journal of Medical Research, 20, 813 - 817.","Lewis, D. J. (1974) Man-biting Simuliidae (Diptera) of Northern India. Israel Journal of Entomology, 9, 23 - 53.","Crosskey, R. W. & Howard, T. H. (1997) A New Taxonomic and Geographical Inventory of World Black Flies (Diptera: Simuliidae). Natural History Museum, London, 144 pp.","Pham, X. D. (1998) New records of six black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 49 (2), 121 - 123."]}

Simulium (Gomphostilbia) quychauense Takaoka & Chen sp. nov. Male. Body length 2.3 mm. Head. Wider than thorax. Upper eye medium brown, consisting of large facets in 14 vertical columns and 14 horizontal rows. Face brownish black, white pruinose. Clypeus brownish black, whitish pruinose, densely covered with golden-yellow scale-like medium-long hairs (mostly directed upward) interspersed with several dark-brown longer hairs. Antenna composed of scape, pedicel and nine flagellomeres, dark brown except scape and pedicel yellow and base of first flagellomere whitish yellow; first flagellomere elongate, 1.8 times length of second one. Maxillary palp light to medium brown, with five segments, proportional lengths of third, fourth, and fifth segments 1.0:1.2:2.5; third segment (Fig. 13 A) slender; sensory vesicle (Fig. 13 A) ellipsoidal, small (0.2 times length of third segment), and with small opening. Thorax. Scutum brownish black, shiny and thinly gray pruinose on prescutellar area when illuminated at certain angles, densely covered with golden-yellow scale-like recumbent short hairs. Scutellum dark brown, covered with yellow short hairs and dark-brown longer upright hairs. Postnotum brownish black, and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum dark brown, longer than deep, moderately covered with fine short hairs. Legs. Foreleg: coxa whitish yellow; trochanter light brown except base yellow; femur medium brown with apical cap dark brown (though apical tip yellowish); tibia light brown except little less than apical one-third brownish black, and outer surface paler medially, and covered with yellow hairs on basal two-thirds of outer surface; tarsus brownish black; basitarsus moderately dilated, 6.9 times as long as its greatest width. Midleg: coxa dark brown; trochanter light brown except base whitish yellow; femur light to medium brown with apical cap dark brown (though apical tip yellow); tibia brownish black except basal one-third whitish yellow; tarsus brownish black except base of basitarsus dark yellow (border not well defined). Hind leg: coxa medium brown; trochanter whitish yellow; femur medium brown with base narrowly whitish yellow and apical cap dark brown (though apical tip whitish yellow); tibia (Fig. 13 B) medium to dark brown except basal two-fifths yellow, and apical cap brownish black; tarsus (Fig. 13 C) medium brown except basal half of basitarsus grayish white (widely covered with dark hairs, thus border not well defined) and basal two-fifths of second tarsomere whitish; basitarsus (Fig. 13 C) enlarged, 4.4 times as long as wide, and 0.9 and 0.8 times as wide as greatest width of tibia and femur, respectively; calcipala (Fig. 13 C) as long as basal width, and 0.4 times as wide as greatest width of basitarsus. Pedisulcus (Fig. 13 C) well developed. Wing. Length 1.9 mm. Costa with dark spinules and hairs except hairs on basal portion yellow. Subcosta without hairs. Hair tuft on base of radius yellow. Basal portion of radius fully haired; R1 with dark spinules and hairs; R2 with hairs only. Basal cell absent. Halter. White except outer surface and basal stem darkened. Abdomen. Basal scale dark brown, with fringe of dark hairs. Dorsal surface of abdomen medium to brownish black, covered with dark-brown short to long hairs; segments 2 and 5���7 each with pair of shiny dorsolateral or lateral patches; ventral surface of abdomen light to dark brown though segments 2���4 paler. Genitalia. Coxites, styles, ventral plate and median sclerite in ventral view as in Fig. 13 D. Coxite in ventral view (Fig. 13 D) nearly rectangular, 1.8 times as long as its greatest width. Style in ventral view (Fig. 13 D) bent inward, nearly parallel-sided, bluntly pointed apically and with apical spine; style in ventrolateral view (Fig. 13 E) shorter than coxite (0.8 times length of coxite), 2.3 times as long as its greatest width at base, tapered to middle, then nearly parallel-sided and with round apex. Ventral plate in ventral view (Fig. 13 D) with body transverse, 0.5 times as long as wide, with anterior margin produced anteromedially, and posterior margin appearing as flattened letter W, lateral margins somewhat emarginated basally, then slightly divergent posteriorly, and densely covered with microsetae on ventral surface; basal arms of moderate length, directed forward, then convergent apically; ventral plate in lateral view (Fig. 13 F) moderately produced ventrally; ventral plate in caudal view (Fig. 13 G) trapezoidal, with ventral margin nearly straight though slightly produced medially, densely covered with microsetae on posterior surface except portion near each lateral tip narrowly bare. Median sclerite (Fig. 13 D, F, H) plate-like and wide. Parameres (Fig. 13 I) of moderate size, each with four or five distinct long to short stout hooks. Aedeagal membrane (Fig. 13 I) moderately setose; dorsal plate not defined. Ventral surface of abdominal segment 10 (Fig. 13 J, K) weakly sclerotized anterolaterally and without distinct hairs near posterior margin. Cercus (Fig. 13 J, K) small, rounded, with 13 or 14 hairs. Pupa. Body length 2.4 mm. Head. Integument yellow, moderately and neatly covered with small round tubercles except antennal sheaths and ventral surface almost bare; antennal sheath without any protuberances; frons with three pairs of unbranched long trichomes with coiled or straight apices (Fig. 14 A); face with pair of unbranched long trichomes with straight apices (Fig. 14 B); three frontal trichomes on each side arising close together, subequal in length to one another and somewhat longer than facial one. Thorax. Integument yellow, moderately covered with round tubercles except dorsolateral portion of posterior half sparsely covered, and with three long dorsomedial trichomes of different lengths (anterior trichome longest, posterior one shortest) with coiled apices (Fig. 14 C), two long anterolateral trichomes with straight apices (anterior trichome more slender and slightly shorter than posterior one) (Fig. 14 D), one medium-long mediolateral trichome with straight apex (Fig. 14 E), and three ventrolateral trichomes with straight apices (one long, two short) (Fig. 14 F) on each side; all trichomes unbranched. Gill (Fig. 14 G) composed of eight slender thread-like filaments, arranged as [(2+1)+(1+2)]+2 from dorsal to ventral, with medium-long common basal stalk having somewhat swollen transparent basal fenestra at base; common basal stalk 0.8���0.9 times length of interspiracular trunk; dorsal and middle triplets sharing short stalk, and dorsal and middle triplets each composed of one individual and two paired filaments and bearing short to medium-long primary and short secondary stalks; stalk of ventral pair of filaments medium-long, 0.9���1.0 times length of common basal stalk, and 0.7���0.8 times length of interspiracular trunk, and 0.9 times as thick as common stalk of middle and dorsal triplets, 1.3 and 1.1 times as thick as stalks of dorsal and middle triplets, respectively; common stalk of dorsal and middle triplets as long as or shorter than primary stalks of dorsal and middle triplets; primary stalks of dorsal and middle triplets each much longer than secondary stalk; primary stalk of dorsal triplet lying against that of lower pair at angle of about 70 degrees when viewed laterally; all filaments damaged losing apical portion, thus no exact lengths known except one of middle triplet, which was intact and 1.9 mm long from base of common basal stalk to apical tip); six filaments of dorsal and middle triplets probably subequal in length and thickness to one another; two filaments of ventral pair probably subequal in length and thickness to each other (outer filament 2.5 mm from base of common basal stalk to broken tip), and 1.7 times as thick as six other filaments when compared basally; all filaments light brown, gradually tapered toward apex; cuticle of all filaments with moderately-defined annular ridges and furrows though becoming less marked apically, densely covered with minute tubercles. Abdomen. Dorsally, all segments light yellow and without tubercles; segment 1 with one unbranched slender medium-long hair-like seta (Fig. 14 H) on each side; segment 2 with one unbranched slender medium-long hair-like seta and five minute setae (Fig. 14 I) submedially on each side; segments 3 and 4 each with four hooked spines and one minute seta on each side; segment 5 with one spine (Fig. 14 J) on right side and lacking spine-combs on left side; segments 6���8 each with spine-combs in transverse row and comb-like groups of minute spines on each side; segments 5���8 each with few minute setae near posterior margin on each side; segment 9 with comb-like groups of minute spines and pair of small terminal hooks (Fig. 14 K, L). Ventrally, segment 4 with one unbranched hook (much smaller in size than those on segments 5���7) and few minute setae (Fig. 14 M) on each side; segment 5 with pair of bifid hooks submedially and few short slender setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer hooks somewhat spaced from each other and few short slender setae on each side; segments 4���8 with comb-like groups of minute spines. Each side of segment 9 with three grapnel-shaped hooklets. Cocoon (Fig. 14 N). Wall-pocket-shaped, thinly and moderately woven except anterolateral and peripheral portions roughly woven, widely extended ventrolaterally; dorsomedial portion of anterior margin slightly produced anteriorly; 3.0 mm long by 2.1 mm wide. Female and larva. Unknown. Type material. HOLOTYPE: Male (with its associated pupal exuviae) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 26, Holotype, Simulium (G.) quychauense, Male, coll. Vietnam, 11-XII-2015, Takaoka et al.], reared from pupa collected from a small stream (width 1.5���3.0 m, bottom of pebbles and sands, water temperature 18 ˚C, exposed to the sun, elevation 73 m, 19˚30���45.487������N/105˚09���09.261������E), moderately flowing in a forest, Chau Dinh, Quy Chau, Nghe An Province, northern Vietnam, 11-XII-2015, by H. Takaoka, M. Sofian-Azirun, C. D. Chen & K.W. Lau. Biological notes. The pupa of this new species was collected from a dead tree leaf. Associated species were S. (G.) chaudinhense sp. nov., S. (S.) nodosum and S. (S.) tani (complex). Distribution. Vietnam (Nghe An). Etymology. The species name quychauense refers to the district name, Quy Chau, where this new species was collected. Remarks. This new species is assigned to the S. asakoae species-group of the subgenus Gomphostilbia by having the yellow hair tuft on the base of the radius, enlarged male hind basitarsi (Fig. 13 C) and ventral plate with lateral margins emarginated basally (Fig. 13 D). This new species is similar to S. (G.) tamdaoense described from a male reared from a pupa in northern Vietnam (Takaoka et al. 2014a) in having the same number of male upper-eye (large) facets in 14 vertical columns and 14 horizontal rows, and relative size of the fore and hind basitarsi. It also is similar to S. (G.) thituyenae described from a female reared from a pupa in southern Vietnam (Takaoka et al. 2015a) in having the small narrow pupal terminal hooks (Fig. 14 L). However, this new species is distinguished from both species by the absence of the spine-combs on abdominal segment 9, and also from S. (G.) tamdaoense by the absence of setae on the basal portion of the paramere (Fig. 13 I) and small narrow pupal terminal hooks (Fig. 14 L). Simulium (Gomphostilbia) sanchayense Takaoka & Lau sp. nov. Simulium (Gomphostilbia) brinchangense: not Takaoka, Sofian-Azirun & Hashim (in Takaoka et al., 2014a): 364���365. This species was previously reported from Vietnam as S. (G.) brinchangense Takaoka, Sofian-Azirun & Hashim, originally described from Peninsular Malaysia (Takaoka et al. 2014a, d). A DNA sequence-based analysis using the COI gene shows that this species is distinct from S. (G.) brinchangense (Low et al. unpublished data). This species is here described as a new species although our morphological reexamination of the males and their associated pupal exuviae collected from Tam Dao, Vinh Phuc Province, reveals that they are almost identical to those of S. (G.) brinchangense except for a few morphological features as noted later. Male. Body length 2.9 mm. Head. Nearly as wide as thorax. Upper eye medium brown, consisting of large facets in 12 vertical columns and 14 horizontal rows. Face brownish black, white pruinose. Clypeus brownish black, whitish pruinose, moderately covered with golden-yellow scale-like medium-long hairs (mostly directed upward) interspersed with several dark-brown longer hairs. Antenna composed of scape, pedicel and nine flagellomeres, medium brown except scape and pedicel yellow and base of first flagellomere whitish yellow; first flagellomere elongate, 1.75 times length of second one. Maxillary palp light to medium brown, with five segments, proportional lengths of third, fourth, and fifth segments 1.0:1.2:2.9; third segment (Fig. 15 A) slender, somewhat produced posteromedially; sensory vesicle (Fig. 15 A) ellipsoidal, small (0.2 times length of third segment), and with opening of medium-size. Thorax. Scutum brownish black except anterolateral calli medium brown, shiny and thinly gray pruinose on shoulders, on wide area along each lateral margin and on prescutellar area when illuminated at certain angles, densely covered with golden-yellow scale-like recumbent short hairs. Scutellum light brown, covered with yellow short hairs and dark-brown longer upright hairs along posterior margin. Postnotum brownish black, shiny and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum dark brown, longer than deep, shiny when illuminated at certain angles, moderately covered with fine short hairs. Legs. Foreleg: coxa whitish yellow; trochanter light brown except base yellow; femur light brown with apical cap medium brown (though apical tip yellowish); tibia white to grayish except little less than apical one-third brownish black, and covered with white and yellow hairs on basal two-thirds of outer surface and white sheen on basal two-thirds of outer surface when illuminated at certain angles; tarsus brownish black; basitarsus moderately dilated, 8.0 times as long as its greatest width. Midleg: coxa medium brown except posterior surface dark brown; trochanter light brown except base whitish yellow; femur light brown with apical cap medium brown (though apical tip yellow); tibia medium brown except basal one-third whitish yellow; tarsus dark brown except basal half of basitarsus dark yellow to light brown (border in middle not well defined). Hind leg: coxa light brown though apical portion whitish yellow; trochanter whitish yellow; femur light brown with base narrowly whitish yellow and apical cap dark brown (though apical tip whitish yellow); tibia (Fig. 15 B) dark brown to brownish black except little less than basal half whitish yellow; tarsus (Fig. 15 C) medium to dark brown except little less than basal half of basitarsus and basal half of second tarsomere yellowish; basitarsus (Fig. 15 C) enlarged, 3.5 times as long as wide, and 1.0 and 1.2 times as wide as greatest width of tibia and femur, respectively; calcipala (Fig. 15 C) slightly shorter than basal width, and 0.3 times as wide as greatest width of basitarsus. Pedisulcus (Fig. 15 C) well developed. Wing. Length 2.1 mm. Costa with dark spinules and hairs except hairs on basal portion yellow. Subcosta with two to four hairs. Hair tuft on base of radius yellow. Basal portion of radius fully haired; R1 with dark spinules and hairs; R2 with hairs only. Basal cell absent. Halter. White except basal stem darkened. Abdomen. Basal scale dark brown, with fringe of dark hairs. Dorsal surface of abdomen medium to dark brown, covered with dark-brown short to long hairs; segments 2 and 5���7 each with pair of shiny dorsolateral or lateral patches; ventral surface of abdomen light to dark brown except segments 2 and 3 pale. Genitalia. Coxites, styles and ventral plate in ventral view as in Fig. 15 D. Coxite in ventral view (Fig. 15 D) nearly rectangular, 1.91 times as long as its greatest width. Style in ventral view (Fig. 15 D) bent inward, nearly parallel-sided, bluntly pointed apically and with apical spine; style in ventrolateral view (Fig. 15 E) shorter than coxite (0.8 times length of coxite), 2.1 times as long as its greatest width at base, slightly tapered to apex, and with truncated apex. Ventral plate in ventral view (Fig. 15 D) with body transverse, 0.6 times as long as wide, with anterior margin produced anteromedially, and posterior margin somewhat concave medially (though posterior margin slightly convex medially), lateral margins slightly emarginated near base, and densely covered with microsetae on ventral surface; basal arms of moderate length, slightly divergent, then convergent apically; ventral plate in lateral view (Fig. 15 F) moderately produced ventrally; ventral plate in caudal view (Fig. 15 G) trapezoidal, with ventral margin nearly straight though slightly produced medially, densely covered with microsetae on posterior surface except portion near each lateral tip narrowly bare. Median sclerite (Fig. 15 H) plate-like and wide. Parameres (Fig. 15 I) of moderate size, each with four distinct long and medium-long stout hooks and several smaller ones including smallest ones on middle part of basal arm. Aedeagal membrane (Fig. 15 I) moderately setose; dorsal plate not defined. Ventral surface of abdominal segment 10 (Fig. 15 J, K) weakly sclerotized anteriorly and without distinct hairs near posterior margin. Cercus (Fig. 15 J, K) small, rounded, with 11 or 12 hairs. Pupa. Body length 2.4 mm. Head. Integument yellow, moderately covered with small round tubercles except antennal sheaths and ventral surface almost bare; antennal sheath without any protuberances; frons with three pairs of unbranched long trichomes with coiled apices (Fig. 16 A); face with pair of unbranched long trichomes with coiled apices (Fig. 16 B); three frontal trichomes on each side arising close together, subequal in length to one another and slightly longer than facial one. Thorax. Integument yellow, moderately covered with round tubercles, and with three long dorsomedial trichomes of different lengths (anterior trichome longest, posterior one shortest) with coiled apices (Fig. 16 C), two long anterolateral trichomes (anterior trichome shorter and more slender than posterior one and with straight apex, and posterior one with coiled apex) (Fig. 16 D), one medium-long mediolateral trichome with straight apex (Fig. 16 E), and three ventrolateral trichomes (one medium-long and two short) with straight apices (Fig. 16 F) on each side; all trichomes unbranched. Gill (Fig. 16 G) composed of eight slender threadlike filaments, arranged as [3+(1+2)]+2 from dorsal to ventral, with medium-long common basal stalk having somewhat swollen transparent basal fenestra at base; common basal stalk 0.65���0.76 times length of inter, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 34-42, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 a) New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam. Zootaxa, 3838 (3), 347 - 366. https: // doi. org / 10.11646 / zootaxa. 3838.3.6","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z. & Hashim, R. (2014 d) Two new species of Simulium (Gomphostilbia) (Diptera: Simuliidae) from Cameron's Highlands, Peninsular Malaysia, with keys to 21 species of the Simulium asakoae speciesgroup. Zootaxa, 3765 (1), 54 - 68."]}

Simulium (Nevermannia) aureohirtum Brunetti, 1911 Simulium aureohirtum Brunetti, 1911: 283 ���288 (Male). Simulium (Nevermannia) aureohirtum: Ogata, 1956: 61 ���62; Ogata, 1966: 129; Takaoka & Roberts, 1988: 194 ���195; Takaoka, 2003: 37���45 (Female, male, pupa and larva). Simulium (Eusimulium) aureohirtum: Puri, 1933c: 1 ���7 (Female, male, pupa and larva); Takaoka, 1979: 382���384 (Female, male, pupa and larva). Specimens examined. Two males (reared from pupae), one pupal exuviae and one mature larva, collected from a stream (width 30 cm, depth 5 cm, bottom sandy, water temperature 18.0˚C, exposed to the sun, elevation 80 m, 19˚20���12.147���N/105˚09���15.908���E) slow flowing near a forest, Chau Dinh, Quy Chau, Nghe An Province, northern Vietnam, 11-XII-2015, by H. Takaoka, M. Sofian-Azirun, C.D. Chen & K.W. Lau. Distribution. India, Bhutan, China, Guam, Indonesia, Japan, Malaysia, Nepal, Pakistan, Philippines, Sri Lanka, Taiwan, Thailand, Vietnam (Lam Dong, Nghe An and Vinh Phuc). Remarks. This species is characterized by the unique female and male genitalia, pupal gill with six filaments and larval head capsule with bold head spots (Takaoka 2003). This is the only autogenous species in the Oriental Region, of which the female can develop the first batch of eggs without blood-meals (Takaoka and Noda 1979). The pupae and larvae of this species appear to be highly adapted to relatively high water temperatures, slow flow and even somewhat muddy or contaminated waters, where most other simuliid species do not occur (Takaoka 2003). As noted previously (Takaoka et al. 2014a), these capabilities, together with other factors, may explain why this species is widely distributed in the Oriental Region and extends into the Palearctic and Australasian Regions. Alternatively, given its wide grographical range, it might be a complex of species., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 68, DOI: 10.5281/zenodo.571608, {"references":["Brunetti, E. (1911) New Oriental Nematocera. Record of Indian Museum, 4, 282 - 288.","Ogata, K. (1956) Notes on Simuliidae of the Ryukyu Islands (Diptera). Japanese Journal of Medical Science and Biology, 9, 59 - 69.","Ogata, K. (1966) Additional notes on Simuliidae of the Ryukyu Islands (Diptera). Kontyu, 34, 123 - 130.","Takaoka, H. & Roberts, D. M. (1988) Notes on blackflies (Diptera: Simuliidae) from Sulawesi, Indonesia. Japanese Journal of Tropical Medicine and Hygiene, 16, 191 - 219.","Puri, I. M. (1933 c) Studies on Indian Simuliidae. Part VIII. Descriptions of larvae, pupae, males and females of S. aureohirtum Brunetti and S. aureum Fries. Indian Journal of Medical Research, 21 (1), 1 - 9.","Takaoka, H. & Noda, S. (1979) Autogeny of the black fly Simulium (Eusimulium) aureohirtum (Diptera: Simuliidae). Journal of Medical Entomology, 15 (2), 183 - 184.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 a) New species and records of black flies (Diptera: Simuliidae) from Vinh Phuc Province, Vietnam. Zootaxa, 3838 (3), 347 - 366. https: // doi. org / 10.11646 / zootaxa. 3838.3.6"]}

Simulium (Gomphostilbia) asakoae Takaoka & Davies, 1995 Simulium (Gomphostilbia) asakoae Takaoka & Davies, 1995: 55 ���60 (Female, male, pupa and larva); Takaoka et al., 2014b: 743; Pham, 1998: 121. Simulium (G.) asakoae was originally described from Peninsular Malaysia (Takaoka and Davies 1995) and recorded from Vietnam (Pham 1998). A reexaminantion shows that the following characters differ from the original description of this species: male antenna yellowish except apical five or six flagellomeres darkened, pupal abdominal segments 1 and 2 without minute tubercles, and larval labral fan with 42���48 primary rays, and length ratio of the antennal articles 1���3 (1.0:0.9���1.0:0.9���1.1). An analysis of DNA sequences shows only a slight difference between S. (G.) asakoae populations from Vietnam and those from Peninsular Malaysia (Low et al. unpublished data). Female. Body length 2.4���2.5 mm. Head. Slightly narrower than width of thorax. Frons brownish black, densely covered with yellowish-white scale-like recumbent short hairs interspersed with few dark longer hairs near vertex; frontal ratio 1.7���1.8:1.0:2.3���2.5; frons:head ratio 1.0:4.6���5.0. Fronto-ocular area well developed, narrow, directed dorsolaterally. Clypeus brownish black, densely covered with yellowish-white scale-like hairs interspersed with several dark longer hairs on each side. Labrum 0.54���0.56 times length of clypeus. Antenna composed of scape, pedicel and nine flagellomeres, light to dark brown except scape and pedicel yellow, and base of first flagellomere yellowish white. Maxillary palp composed of five segments, light to medium brown, proportional lengths of third, fourth, and fifth segments 1.0:1.1���1.2:2.8���2.9; third segment (Fig. 4 A, B) widened apically; sensory vesicle (Fig. 4 A, B) small or medium sized, ellipsoidal (0.3���0.4 times length of third segment), with medium or large opening. Maxillary lacinia with 9���12 inner and 13 or 14 outer teeth. Mandible (Fig. 4 C) with 22 or 23 inner teeth and five or six outer teeth at some distance from tip. Cibarium (Fig. 4 D) medially forming sclerotized plate folded forward from posterior margin, with moderately sclerotized mediolongitudinal ridge with bifid apex. Thorax. Scutum dark brown except anterolateral calli ochreous, and three blackish longitudinal vittae (one median, two submedian), thinly pruinose and shiny when illuminated at certain angles, densely covered with whitish-yellow to yellow scale-like recumbent short hairs except three vittae with dark recumbent short hairs. Scutellum medium brown, covered with yellow short hairs and dark-brown long upright hairs along posterior margin. Postnotum dark brown, slightly shiny when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum longer than deep, medium to dark brown, shiny when illuminated at certain angles, moderately covered with fine short hairs. Legs. Foreleg: coxa and trochanter yellowish white; femur dark yellow with apical cap light brown (though extreme tip yellowish, and basal two-thirds of inner surface yellowish white); tibia white except apical three-tenths dark brown, and little more than basal one-fourth grayish on inner surface, and covered with white fine hairs on basal four-fifths; tarsus brownish black, with moderate dorsal hair crest; basitarsus moderately dilated, 6.0���6.4 times as long as its greatest width. Midleg: coxa medium brown except posterolateral surface dark brown; trochanter whitish yellow; femur light brown with basal one-fifth whitish yellow and apical cap medium brown (though extreme tip yellowish); tibia yellowish white on basal three-fourths to four-fifths (though apical two-thirds of anterior surface appearing darkened due to dark hair covering) and apical cap brownish black, covered with yellowish fine hairs on posterior and inner surfaces of basal two-thirds; tarsus dark brown to brownish black though basal half of basitarsus yellowish white. Hind leg: coxa light brown except apical one-third yellowish; trochanter whitish yellow; femur light brown with base whitish yellow and apical cap dark brown (though extreme tip yellowish white); tibia (Fig. 4 E) yellowish white on basal two-thirds and brownish black on rest, covered with whitish fine hairs on outer and posterior surfaces of little more than basal three-fourths; tarsus brownish black except basal two-thirds (though base light brown) and basal half of second tarsomere yellowish white; basitarsus (Fig. 4 F) narrow, nearly parallel-sided though slightly narrowed apically, 5.5���6.2 times as long as wide, and 0.7 and 0.6���0.7 times as wide as greatest widths of tibia and femur, respectively; calcipala (Fig. 4 F) nearly as long as width at base, and 0.6 times as wide as greatest width of basitarsus; pedisulcus (Fig. 4 F) well developed; claw (Fig. 4 G) with large basal tooth 0.46���0.50 times length of claw. Wing. Length 2.0��� 2.1 mm. Costa with dark spinules and hairs except basal patch of hairs yellow. Subcosta with dark hairs except near apex bare. Hair tuft on base of radius yellow. Basal portion of radius fully haired; R1 with dark spinules and hairs; R2 with hairs only. Basal cell absent. Halter. White except basal portion darkened. Abdomen. Basal scale ochreous, with fringe of whitish-yellow hairs. Dorsal surface of abdomen medium to dark brown except anterior half or little more of segment 2 whitish, moderately covered with dark short to long hairs; tergites of segments 2 and 6���9 shiny when illuminated at certain angles. Ventral surface of segment 2 white, those of segments 3 and 4 dark yellow to light brown and those of other segments medium brown; sternal plate on segment 7 undeveloped. Terminalia. Sternite 8 (Fig. 4 H) bare medially, with 18���22 medium-long to long hairs together with four or five slender short hairs on each side. Ovipositor valve (Fig. 4 H) triangular (though posteromedial corner rounded), thin, membranous, moderately covered with microsetae interspersed with one or two short hairs; inner margins slightly sinuous, somewhat sclerotized, and moderately separated from each other. Genital fork (Fig. 4 I) of usual inverted- Y form, with slender stem; arms of moderate width, moderately folded medially, without lobe directed posteromedially. Paraproct in ventral view (Fig. 4 J) somewhat concave anterolaterally, with six sensilla on anteromedial surface; paraproct in lateral view (Fig. 4 K) slightly produced ventrally beyond ventral tip of cercus, 0.6���0.7 times as long as wide, with 22���27 medium-long to long hairs on ventral and lateral surfaces. Cercus in lateral view (Fig. 4 K) short, rounded posteriorly, 0.4 times as long as wide. Spermatheca (Fig. 4 L) ellipsoidal, 1.4��� 1.5 times as long as its greatest width, well sclerotized except duct and small area near juncture with duct unsclerotized, and with many fissures on outer surface; internal setae absent; both accessory ducts slender, subequal in diameter to major one. Male. Body length 2.5���2.6 mm. Head. Somewhat wider than thorax. Upper eye bright medium brown, consisting of 11 (rarely 12) vertical columns and 13 (rarely 14) horizontal rows of large facets. Face brownish black, white pruinose. Clypeus brownish black, whitish pruinose, densely covered with golden-yellow scale-like medium-long hairs (mostly directed upward) interspersed with several dark-brown simple longer hairs. Antenna composed of scape, pedicel and nine flagellomeres, yellowish except flagellomeres 5���9 light to medium brown (or yellow to dark yellow except base of flagellomere 1 yellowish white and flagellomeres 8 and 9 light to medium brown in one male); first flagellomere elongate, 1.7 times length of second one. Maxillary palp light to medium brown, with five segments, proportional lengths of third, fourth, and fifth segments 1.0:1.2���1.3:3.0���3.2; third segment (Fig. 5 A, B) slender; sensory vesicle (Fig. 5 A, B) small, globular or ellipsoidal (0.2 times length of third segment), and with small opening. Thorax. Scutum dark brown, with longitudinal vittae (one median, two submedian) invisible or faintly visible, shiny and thinly gray pruinose when illuminated at certain angles, and densely covered with whitish-yellow scale-like recumbent short hairs. Scutellum medium brown, covered with yellow short hairs and dark-brown long upright hairs along posterior margin. Postnotum dark brown, slightly shiny and white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum medium to dark brown, longer than deep, shiny when illuminated at certain angles, moderately covered with fine short hairs. Legs. Foreleg: coxa whitish yellow; trochanter yellow; femur dark yellow to light brown with apical cap medium brown (though apical tip yellowish); tibia white except apical three-tenths dark brown, and covered with white hairs on white portion; tarsus brownish black; basitarsus moderately dilated, 7.1���7.4 times as long as its greatest width. Midleg: coxa light brown except posterior surface dark brown; trochanter yellowish; femur light brown with base yellowish and apical cap medium brown (though apical tip yellow); tibia medium to dark brown except basal one-third or little more whitish; tarsus dark brown except basal one-third or less of basitarsus yellow (border not well defined). Hind leg: coxa light brown except apical portion yellow; trochanter yellowish; femur medium brown with base yellowish white and apical cap dark brown (though apical tip yellow); tibia (Fig. 5 C) dark brown to brownish black except basal three-sevenths yellowish white; tarsus (Fig. 5 D) medium to dark brown except little less than basal half of basitarsus and basal half of second tarsomere whitish yellow; basitarsus (Fig. 5 D) enlarged, wedge-shaped, 3.3���3.5 times as long as wide, and 1.0���1.1 and 1.1���1.3 times as wide as greatest width of tibia and femur, respectively; calcipala (Fig. 5 D) slightly shorter than basal width, and 0.3 times as wide as greatest width of basitarsus. Pedisulcus (Fig. 5 D) well developed. Wing. Length 2.0 mm. Other characters as in female except subcosta with one to three hairs (rarely no hairs). Halter. Dull white except basal stem darkened. Abdomen. Basal scale dark brown, with fringe of light-brown hairs. Dorsal surface of abdomen dark brown to brownish black except segment 2 light brown, covered with dark-brown short to long hairs except segment 2 with yellowish hairs; segments 2 and 5���8 each with pair of shiny dorsolateral or lateral patches; ventral surface of segment 2 whitish, those of segments 3 and 4 grayish white though sternal plates light brown, and those of other segments medium to dark brown. Genitalia. Coxite in ventral view (Fig. 5 E) nearly rectangular, 1.7 times as long as its greatest width. Style in ventral view (Fig. 5 E) bent inward, with triangular apex having single spine; style in ventrolateral view (Fig. 5 F) slightly tapered toward apex, with truncated apex. Ventral plate in ventral view (Fig. 5 E) with body transverse, 0.6 times as long as wide, with anterior margin produced anteromedially, posterior margin somewhat concave medially, and lateral margin emarginated medially, and densely covered with microsetae on ventral surface; basal arms of moderate length, slightly divergent, then convergent apically; ventral plate in lateral view (Fig. 5 G) moderately produced ventrally; ventral plate in caudal view (Fig. 5 H) rounded ventrally, though ventral margin nearly straight medially, densely covered with microsetae on posterior surface. Median sclerite (Fig. 5 I) plate-like, wide. Parameres (Fig. 5 J) of moderate size, each with four distinct long and medium-long stout hooks, and without minute setae on outer surface of basal arm. Aedeagal membrane (Fig. 5 J) moderately setose; dorsal plate not defined. Ventral surface of abdominal segment 10 (Fig. 5 K, L) slightly sclerotized along anterior margin and without distinct hairs near posterolateral corners. Cercus (Fig. 5 K, L) small, rounded, with 12���17 hairs. Pupa. Body length 2.5���2.7 mm. Head. Integument yellow, moderately covered with small round tubercles except antennal sheaths and ventral surface almost bare; antennal sheath without any protuberances; frons with three pairs of unbranched long trichomes with or without coiled apices (Fig. 6 A); face with pair of unbranched (rarely bifid) long trichomes with straight apices (Fig. 6 A); three frontal trichomes on each side arising close together, subequal in length to one another and slightly longer than facial one. Thorax. Integument yellow, moderately covered with round tubercles, and with three long dorsomedial trichomes of different lengths (anterior trichome longest, posterior one shortest) with coiled apices (Fig. 6 A), two long anterolateral trichomes (anterior trichome more slender and shorter with straight apex, posterior one with coiled apex) (Fig. 6 A), one medium-long mediolateral trichome with straight apex (Fig. 6 A), and three ventrolateral trichomes (one medium-long, two short) with straight apices (Fig. 6 A) on each side; all trichomes unbranched except dorsal trichomes rarely bifid. Gill (Fig. 6 B) composed of eight slender thread-like filaments, arranged as [3+(1+2)]+2 or [(2+1)+(1+2)]+2 from dorsal to ventral, with short common basal stalk having somewhat swollen transparent basal fenestra at base; common basal stalk 0.6 times length of interspiracular trunk; dorsal and middle triplets sharing short stalk, and dorsal triplet composed of three individual filaments arising at same level, with short stalk, or composed of one individual and two paired filaments with extremely short stalk, middle triplet composed of one individual and two paired filaments and bearing short primary and secondary stalks; stalk of ventral pair of filaments medium-long, 1.4���1.7 times length of common basal stalk, and 0.8���1.0 times length of interspiracular trunk, and 0.9 times as thick as common stalk of middle and dorsal triplets; common stalk of dorsal and middle triplets shorter than primary stalk of middle triplet, and shorter or longer than stalk of dorsal triplet; middle triplet primary stalk longer than secondary stalk; primary stalk of dorsal triplet lying against that of lower pair at angle of 70���90 degrees when viewed laterally; filaments of dorsal triplet subequal in length (1.4���2.0 mm) and thickness to one another; filaments of middle triplet subequal in length (1.8���2.7 mm) and thickness to one another; two filaments of ventral pair subequal in length (2.6���3.2 mm) and thickness to each other and 1.4 and 1.3 times as thick as dorsal and middle triplets of filaments when compared basally; all filaments medium to dark brown, gradually tapered toward apex; cuticle of all filaments with well-defined annular ridges and furrows though becoming less marked apically, densely covered with minute tubercles. Abdomen (Fig. 6 C, E). Dorsally, segments 1 and 2 and basal half or more of segment 3 (and rarely segment 4) light grayish, and other segments yellowish; all segments without tubercles; segment 1 with one unbranched slender medium-long hair-like seta on each side; segment 2 with one unbranched slender medium-long hair-like seta and five somewhat spinous minute setae submedially on each side; segments 3 and 4 each with four hooked spines and one somewhat spinous minute seta on each side; segment 5 lacking spinecombs and comb-like groups of minute spines on each side; segments 6���9 each with spine-combs in transverse row and comb-like groups of minute spines on each side (though spine-combs rarely absent on segment 9); segments 5��� 8 each with few minute setae near posterior margin on each side; segment 9 with pair of wide flat terminal hooks, of which outer margin is 3.5���4.1 times length of inner margin and crenulated (Fig. 6 D) when viewed caudally. Ventrally, segment 4 with one unbranched hook (subequal in size to those on segments 5���7) and few slender short setae on each side; segment 5 with pair of bifid hooks submedially and few short slender setae on each side; segments 6 and 7 each with pair of bifid (rarely trifid) inner and unbranched outer hooks somewhat spaced from each other and few short slender setae on each side; segments 4���8 each with comb-like groups of minute spines. Each side of segment 9 with three or four grapnel-shaped hooklets (Fig. 6 F). Cocoon (Fig. 6 G). Wall-pocketshaped, roughly to moderately woven, widely extended ventrolaterally; anterior margin thickly woven medially, often with buldge; posterior three-fifths with floor roughly woven; individual threads visible; 3.4���4.0 mm long by 2.0���3.0 mm wide. Mature larva. Body length 5.0��� 5.6 mm. Body light ochreous except ventral surface of abdominal segments 5��� 9 whitish, with following color markings: thoracic segment 1 encircled with reddish-brown band (though disconnected ventromedially) narrowly along anterior margin, thoracic segments 2 and 3 reddish brown on ventral surface; abdominal segment 3 with or without pair of narrow reddish-brown lateral spots; abdominal segment 4 with pair of reddish-brown dorsolateral spots rarely faintly connected to each other ventrally, abdominal segments 5 and 6 each encircled by reddish-brown transverse band though disconnected ventromedially (often faded out leaving round dorsomedian spot) and three similar colored spots on ventral surface, though those on segment 6 much lighter, abdominal segments 7���9 each covered with similar colored pigments to varying extent (as transverse band similar to those on segments 5 and 6 in some larvae, but completely faded out in other larvae) on dorsal and dorsolateral surface; abdominal segment 7 with similar colored transverse band ventrally (though usually faded out in most larvae). Head. Head capsule (Fig. 7 A���C) yellow to dark yellow except eye-spot region whitish, sparsely covered with minute setae (though moderately to densely on dorsal surface); head spots moderately positive though anterior spots of posterolateral spots usually faint or indistinct (Fig. 7 A); eyebrow distinct with small round dark spot above it (Fig. 7 B). Antenna composed of three articles and apical sensillum, longer than stem of labral fan; proportional lengths of first, second, and third articles 1.0:0.9���1.0:0.9���1.1. Labral fan with 42���48 primary rays. Mandible (Fig. 7 D) with three comb-teeth decreasing in length from first tooth to third; mandibular serration composed of two teeth (one medium-sized, one small); major tooth at angle of little less than 90 degrees against mandible on apical side; supernumerary serrations absent. Hypostoma (Fig. 7 E) with row of nine apical teeth, of which median tooth is longer than each corner tooth; lateral margin smooth; five or six hypostomal bristles per side lying nearly parallel to lateral margin. Postgenal cleft (Fig. 7 C) arrow-head-shaped, medium-long, 2.2���2.7 times length of postgenal bridge. Cervical sclerites composed of pair of small yellow rod-like pieces. Thorax and Abdomen. Thoracic proleg without hairs; thoracic cuticle and abdominal cuticle of segments 1 and 2 sparsely covered with unbranched unpigmented minute setae on dorsal surface; abdominal cuticle of segments 3���5 sparsely covered with unbranched dark minute setae and unpigmented minute setae on dorsal surface, that of segments 6���9 moderately covered with s, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 15-23, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Davies, D. M. (1995) The Black Flies (Diptera: Simuliidae) of West Malaysia. Kyushu University Press, Fukuoka, viii + 175 pp.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 b) Female black flies of Simulium (Diptera: Simuliidae) collected on humans in Tam Dao National Park, Vietnam: Description of a new species and notes on four species newly recorded from Vietnam. Tropical Biomedicne, 31 (4), 742 - 748.","Pham, X. D. (1998) New records of six black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 49 (2), 121 - 123.","Ishii, Y., Choochote, W., Bain, O., Fukuda, M., Otsuka, Y. & Takaoka, H. (2008) Seasonal and diurnal biting activities and zoonotic filarial infections of two Simulium species (Diptera: Simuliidae) in northern Thailand. Parasite, 15, 121 - 129. https: // doi. org / 10.1051 / parasite / 2008152121"]}

Simulium (Simulium) xuandei Takaoka & Pham, 2015 Simulium (Simulium) xuandei Takaoka & Pham (in Takaoka et al., 2015a): 86���93 (Female, male, pupa and larva). Specimens examined. Three females and two males (all reared from pupae), collected from a stream (width 1.5��� 4.0 m, depth 10���20 cm, bottom of pebbles and rocks, water temperature 18.0˚C, exposed to the sun, elevation 107 m, 19˚30���10.540���N/105˚09���17.144���E), moderately flowing near a natural forest, Chau Dinh, Quy Chau, Nghe An Province, northern Vietnam, 11-XII-2015, by H. Takaoka, M. Sofian-Azirun, C.D. Chen & K.W. Lau. Distribution. Vietnam (Lam Dong and Nghe An) Remarks. This species was described from Lam Dong Province, southern Vietnam (Takaoka et al. 2015a), and also recorded from Nghe An Province, northern Vietnam by our surveys. The molecular data show that this species includes two additional cryptic taxa (Low et al. 2016)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 153, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

Simulium (Simulium) hirtinervis Edwards, 1928 Simulium (Simulium) hirtinervis Edwards, 1928: 63 ���64 (Female): Takaoka and Davies, 1995: 115 ���120 (Female, male, pupa and larva). Distribution. Peninsular Malaysia and Vietnam (Ha Tay and Hoa Binh). Remarks. This species was originally described from Peninsular Malaysia based on females by Edwards (1928) and later its female was redescribed and its male, pupa and larva were described by Takaoka and Davies (1995). This species was recorded from Vietnam by Pham (1998)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 116, DOI: 10.5281/zenodo.571608, {"references":["Edwards, F. W. (1928) Diptera Nematocera from the Federated Malay States Museums. Journal of Federated Malay State Museum, 14, 1 - 139.","Takaoka, H. & Davies, D. M. (1995) The Black Flies (Diptera: Simuliidae) of West Malaysia. Kyushu University Press, Fukuoka, viii + 175 pp.","Pham, X. D. (1998) New records of six black fly species (Diptera: Simuliidae) from Vietnam. Medical Entomology and Zoology, 49 (2), 121 - 123."]}

Simulium (Nevermannia) phami Takaoka, Sofian-Azirun & Ya���cob, 2014 Simulium (Nevermannia) phami Takaoka, Sofian-Azirun & Ya���cob (in Takaoka et al., 2014c): 563���566 (Female, male, pupa and larva). Distribution. Vietnam (Lam Dong). Remarks. This species was described from Lam Dong Province, southern Vietnam (Takaoka et al. 2014c). It is characterized by the pupal gill with five filaments., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 67-68, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2014 c) Three new species of Simulium (Nevermannia) (Diptera: Simuliidae) from Vietnam. Zootaxa, 3866 (4), 555 - 571."]}

Simulium (Gomphostilbia) dachaisense Takaoka & Lau, 2015 Simulium (Gomphostilbia) dachaisense Takaoka & Lau (in Takaoka et al., 2015a): 28���34 (Female, male, pupa and larva). Distribution. Vietnam (Lam Dong). Remark. This species was described from Lam Dong Province in southern Vietnam (Takaoka et al. 2015a)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 52, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

Simulium (Gomphostilbia) hmongense Takaoka & Ya���cob sp. nov. Pharate Male. Only following characters observed. Upper-eye facets in 17 vertical columns and 17 horizontal rows. Antenna composed of scape, pedicel and nine flagellomeres. Sensory vesicle small and rounded. Hind basitarsus (Fig. 9 A) enlarged. Costa with spinules and hairs. Basal portion of radius haired. Pupa. Body length 3.4 mm. Head. Integument yellow, moderately covered with small round tubercles; antennal sheath without any protuberances; frons with three pairs of unbranched long trichomes with coiled or straight apices (Fig. 9 B); face with pair of unbranched medium-long trichomes with straight apices (Fig. 9 C); three frontal trichomes on each side arising close together, subequal in length to one another and somewhat longer than facial one. Thorax. Integument yellow except narrow mediolongitudinal portion of dorsal surface darkened, sparsely covered with small round tubercles, with three long anterodorsal trichomes with coiled apices (Fig. 9 D), two long anterolateral trichomes (anterior trichome somewhat shorter than posterior one and with straight apex, posterior trichome with coiled apex) (Fig. 9 E), mediolateral trichome lost, and three ventrolateral trichomes with straight apices (one medium-long, two short) (Fig. 9 F), on each side; all trichomes unbranched. Gill (Fig. 9 G) composed of eight slender thread-like filaments, arranged as [(2+1)+(2+1)]+2 from dorsal to ventral; common basal stalk medium-long, 0.8 times length of interspiracular trunk, having somewhat swollen basal fenestra at base; dorsal and middle triplets sharing medium-long common stalk 0.9 times length of common basal stalk; dorsal triplet composed of one individual and two paired filaments with short primary and secondary stalk in left gill or composed of three individual filaments arising at same level from short stalk in right gill; primary stalk directed inward and slightly upward, thus appearing to be hidden behind middle triplet; middle triplet directed forward, composed of one individual filament and two paired filaments with long primary and medium-long secondary stalks; stalk of ventral pair directed downward, then forward, 0.9 times as long as primary stalk of middle triplet and 1.3 times length of interspiracular trunk; stalk of ventral pair 0.8 times as thick as common stalk of dorsal and middle triplets, 1.1 and 1.3 times as thick as primary stalks of middle and dorsal triplets respectively; all filaments grayish light-brown, gradually tapered toward apices; lengths of filaments probably little longer than 3.0 mm (exact length of filaments not measurable due to loss of apical portions of all filaments); filaments of dorsal and middle triplets subequal in length and thickness to one another, and appearing to be slightly shorter and thinner than ventral paired filaments; cuticle of all filaments with well-marked annular ridges and furrows, which are, though, becoming less distinct apically, and densely covered with minute tubercles, relatively larger ones on ridges. Abdomen. Dorsally, segments 1���4 grayish light-brown, segment 9 yellowish, other segments unpigmented; segment 1 with one unbranched slender medium-long hair-like seta (Fig. 9 H) on each side; segment 2 with one unbranched slender short hair-like seta (Fig. 9 I) and four short somewhat spinous setae submedially near posterior margin on each side; segments 3 and 4 each with four hooked spines and one short somewhat spinous seta near posterior margin on each side; segments 5���8 each with two unbranched short setae near posterior margin on each side; segments 5���9 each comb-like groups of minute spines near anterior margin; segments 6���9 each with spinecombs in transverse row on each side; segment 9 with pair of small narrow blunt terminal hooks with rugged surface apically (Fig. 9 J, K). Ventrally, segment 4 with one unbranched hook and few unbranched short setae on each side; segment 5 with pair of bifid hooks submedially and few unbranched short slender setae on each side; segments 6 and 7 each with pair of bifid inner and unbranched outer hooks somewhat spaced from each other and few unbranched short slender setae on each side; segments 4���8 each with comb-like groups of minute spines. Each side of segment 9 with two grapnel-shaped hooklets. Cocoon (Fig. 9 L). Wall-pocket-shaped, moderately and thinly woven with no spaces in webs, widely extended ventrolaterally; anterior margin somewhat thickly woven, with long anterodorsal projection directed forward; posterior half with floor roughly woven; individual threads partially visible; 4.0 mm long by 3.6 mm wide. Mature larva. Body length 5.0��� 5.5 mm. Body creamy except abdominal segments 1���3 greenish and dorsal and dorsolateral surface of abdominal segments 4���9 light ochreous, with color markings as follows: thoracic segment 1 with reddish-brown transverse band (though disconnected ventromedially), dorsal surface of thorax thinly pinkish, ventral surface of thoracic segments 2 and 3 reddish brown, abdominal segment 3 thinly reddish brown entirely or partially or not, abdominal segments 4���8 entirely or partially reddish brown dorsally, dorsolaterally and ventrally (in particular markings on dorsal surface of segments 5 and 6 distinct). Head. Head capsule whitish yellow to yellow, with faint positive head spots, and sparsely covered with unpigmented minute setae (though moderately on dorsal surface). Antenna composed of three articles and apical sensillum, longer than stem of labral fan; proportional lengths of first, second, and third articles 1.0:0.9���1.0:0.9. Labral fan with 42���44 primary rays. Mandible (Fig. 10 A) with three comb-teeth decreasing in length from first tooth to third; mandibular serration composed of two teeth (one medium-sized, one small) (left mandible in one larva with additional small tooth at base of major tooth); major tooth at acute angle against mandible on apical side; supernumerary serrations absent. Hypostoma (Fig. 10 B) with row of nine apical teeth, of which median tooth is slightly longer than each corner tooth; lateral margin smooth; four hypostomal bristles per side lying slightly divergent posteriorly from lateral margin. Postgenal cleft (Fig. 10 C) short, nearly quadrate, 0.9 times as long as wide, and 0.7 times length of postgenal bridge. Cervical sclerites composed of pair of yellow small rod-like pieces. Thorax and Abdomen. Thoracic proleg without hairs; thoracic cuticle bare; abdominal cuticle bare except last abdominal segment moderately covered with colorless unbranched setae on each side of anal sclerite (even down to base of ventral papilla on each side); thorax and abdomen without dorsal protuberances. Rectal scales present, unpigmented. Rectal organ compound, each of three lobes with several finger-like secondary lobules (exact number of secondary lobules uncountable). Anal sclerite of usual X-form, with anterior arms 1.2 times length of posterior ones, broadly sclerotized at base; no sensilla on broad base and posterior to posterior arms; accessory sclerite absent. Last abdominal segment with pair of large conical ventral papillae. Posterior circlet with 70 rows of hooklets with up to 12 hooklets per row. Type material. HOLOTYPE: Pupa (pharate male) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 25, Holotype, Simulium (G.) hmongense, Pharate male, coll. Vietnam, 20-XII-2014, Takaoka et al.], collected from a small stream (width 0.2 m, depth 2 cm, bottom rocky, water temperature 7.0˚C, partially shaded, elevation 1,893 m, 22˚21���28.378���N/103˚45���52.084���E) slowly flowing in shrub, Lai Chau, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. PARATYPES: Two mature larvae in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 25, Paratype, Simulium (G.) hmongense, Larvae, coll. Vietnam, 20-XII-2014, Takaoka et al.], collected from a stream (width 0.2 m, depth 5 cm, bottom sandy and muddy, water temperature 8.0˚C, exposed to the sun, elevation 1,925 m, 22˚21���11.767���N/103˚46���28.309���E) slowly flowing in shrub in grassland, Lai Chau, Sapa, Lao Cai Province, northern Vietnam, 20-XII-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya���cob, C.D. Chen & K.W. Lau. Biological notes. The pupa and larvae of this new species were collected from plastic sheets in the current. Associated species were S. (M.) nigrofilum sp. nov., S. (N.) maeaiense and S. (S.) daoense sp. nov. Etymology. The species name hmongense refers to the land in which the Hmong tribe lives. Remarks. This new species may be assigned to one of the three species-groups (S. asakoae, S. ceylonicum and S. darjeelingense species-groups) of the subgenus Gomphostilbia, redefined by Takaoka (2012), by having the enlarged male hind basitarsus (Fig. 9 A). This new species is placed in the S. asakoae species-group due to the similarity of the unique pupal terminal hooks (Fig. 9 J, K) to those of S. (G.) lurauense Takaoka, Sofian-Azirun & Hashim from Peninsular Malaysia and S. (G.) thituyenae Takaoka & Pham from Vietnam, both of which are members of the S. asakoae species-group (Takaoka et al. 2011, 2015a). This new species is characterized by the greater number of male upper-eye facets in 17 vertical columns and 17 horizontal rows, pupal thoracic integument sparsely covered with tubercles, middle triplet of the gill with a long primary stalk (Fig. 9 G), cocoon with a long anterodorsal projection (Fig. 9 L), and small larval postgenal cleft (Fig. 10C). Among the species of the S. asakoae species-group, only two species, S. (G.) chiangdaoense Takaoka & Srisuka from Thailand and S. (G.) fuscidorsum Takaoka & Ya���cob from Vietnam, have the cocoon with a long anterodorsal projection (Takaoka and Srisuka 2009; Takaoka et al. 2015a). However, S. (G.) chiangdaoense differs by having the number of male upper-eye facets in 13 or 14 vertical columns and 15 or 16 horizontal rows, pupal thoracic integument moderately covered with tubercles and middle triplet of the pupal gill with a short primary stalk, and S. (G.) fuscidorsum differs by having the pupal thoracic integument moderately covered with tubercles, long common basal stalk of the pupal gill, and shape of the terminal hooks, of which the outer margin is longer than the inner one and crenulated. Out of seven species among the S. ceylonicum species-group, which have the cocoon with a long anterodorsal projection, S. (G.) inthanonense Takaoka & Suzuki described from Thailand (Takaoka and Suzuki 1984) has a similar number of male upper-eye facets (16 vertical columns and 16 horizontal rows) and small larval postgenal cleft, but is distinguished from this new species by the ellipsoidal male sensory vesicle, arrangement of the pupal gill filaments (length ratio of the primary stalk of the middle triplet against the stalk of the ventral pair is 0.6���0.7, whereas it is 1.1 in this new species) and shape of the terminal hooks, of which the outer margin is much longer than the inner one. Another species, S. (G.) ogatai (Rubtsov) described from Japan (Rubtsov 1959 ���1964), shares a similar number of male upper-eye facets in 14 or 15 vertical columns and 16 horizontal rows, and similar small pupal terminal hooks, but differs by the arrangement of the pupal gill filaments (length ratio of the primary stalk of the middle triplet against the stalk of the ventral pair is 0.4���0.5, whereas it is 1.1 in this new species), and dorsal surface of pupal abdominal segments 1���4 unpigmented. (Characters of S. (G.) ogatai used here are based on specimens collected in Gifu, Japan, in July 17, 2011 by Dr. Y. Otsuka). All five species of the S. darjeelingense species-group have simple wall-pocket-shaped cocoons, thus differing from this new species., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 26-30, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Srisuka, W. (2009) Simulium (Gomphostilbia) chiangdaoense sp. nov. (Diptera: Simuliidae) from northern Thailand. Medical Entomology and Zoology, 60 (4), 269 - 276.","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96.","Takaoka, H. & Suzuki, H. (1984) The blackflies (Diptera: Simuliidae) from Thailand. Japanese Journal of Sanitary Zoology, 35 (1), 7 - 45.","Rubtsov, I. A. (1959 - 1964) Simuliidae (Melusinidae). In: Lindner, Die Fliegen der Palaearktischen Region, 14: 1 - 689."]}

Simulium (Gomphostilbia) thituyenae Takaoka & Pham, 2015 Simulium (Gomphostilbia) thituyenae Takaoka & Pham (in Takaoka et al., 2015a): 24 –28 (Female and pupa) Distribution. Vietnam (Lam Dong). Remarks. This species was described from Lam Dong Province in southern Vietnam (Takaoka et al. 2015a). The male and larva of this species are still unknown. Simulium (Gomphostilbia) vinhphucense Takaoka & Low sp. nov. Male. Body length 2.5 mm. Nearly as in male of S. (G.) sanchayense sp. nov. except following characters. Head. Upper eye medium brown, consisting of large facets in 9 vertical columns and 11 or 12 horizontal rows. Antenna medium brown except scape and pedicel yellow, base of first flagellomere whitish yellow, and rest of first flagellomere and second and third flagellomeres yellow to dark yellow; first flagellomere elongate, 1.7 times length of second one. Maxillary palp: proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.4; third segment (Fig. 21 A) slender; sensory vesicle (Fig. 21 A) ellipsoidal, small (0.2 times length of third segment), and with small opening. Thorax. Scutum dark brown except anterolateral calli ochreous, with faint longitudinal vittae (one median and two submedian), shiny and thinly gray pruinose on entire surface. Legs. Fore and mid trochanters and base of mid femur yellow. Fore basitarsus moderately dilated, 8.2 times as long as its greatest width. Hind basitarsus (Fig. 21 B) enlarged, 3.3 times as long as wide, and 1.1 and 1.5 times as wide as greatest width of tibia and femur, respectively; calcipala (Fig. 21 B) slightly shorter than basal width, and 0.2 times as wide as greatest width of basitarsus. Wing. Length 2.0 mm. Subcosta with two hairs. Abdomen. Dorsal surface of abdomen medium to dark brown except segment 2 pale though narrow portion along posterior margin somewhat darkened; tergites 3– 6 each with markedly lighter medial portion; ventral surface of abdomen light to medium brown except segment 2– 4 pale though sternites 3 and 4 somewhat darkened. Genitalia. Coxite in ventral view (Fig. 21 C) nearly rectangular, twice as long as its greatest width. Style in ventral view (Fig. 21 C) bent inward, bluntly rounded apically and with apical spine; style in ventrolateral view (Fig. 21 D) 0.8 times length of coxite, gradually tapered from base to apex, and with truncated apex. Ventral plate in ventral view (Fig. 21 C) with body transverse, 0.5 times as long as wide, with anterior margin produced anteromedially, and posterior margin slightly concave medially, lateral margins nearly straight or slightly emarginated basally, and densely covered with microsetae on ventral surface; basal arms of moderate length, directed forward, then convergent apically; ventral plate in lateral view (Fig. 21 E) moderately produced ventrally; ventral plate in caudal view (Fig. 21 F) rounded ventrally, densely covered with microsetae on posterior surface except portion near each lateral tip narrowly bare. Median sclerite plate-like, wide (Fig. 21 G). Parameres (Fig. 21 H) of moderate size, each with four distinct long and medium-long stout hooks and several smaller ones. Aedeagal membrane (Fig. 21 H) moderately setose; dorsal plate not defined. Ventral surface of abdominal segment 10 (Fig. 21 I, J) without distinct hairs near posterior margin. Cercus (Fig. 21 I, J) small, rounded, with 12 or 14 hairs. Pupa. Body length 2.6 mm. Nearly as in pupa of S. (G.) sanchayense sp. nov. except following characters. Head. Frons with three pairs of unbranched long trichomes with straight or coiled apices; face with pair of unbranched long trichomes with straight or coiled apices. Thorax. Three unbranched ventrolateral trichomes (one medium-long with coiled apex, two short with straight apices) on each side. Gill (Fig. 21 K) composed of eight slender thread-like filaments, arranged as [(1+2)+(1+2)]+2 from dorsal to ventral, with medium-long common basal stalk having somewhat swollen transparent basal fenestra at base; common basal stalk 0.7 times length of interspiracular trunk; dorsal and middle triplets sharing short stalk, and each triplet composed of one individual and two paired filaments and bearing short primary and secondary stalks; stalk of ventral pair of filaments mediumlong, 0.8–1.0 times length of common basal stalk, and 0.6 times length of interspiracular trunk, and 0.8–0.9 times as thick as common stalk of middle and dorsal triplets and 1.2–1.3 times as thick as primary stalks of dorsal and middle triplets; common stalk of dorsal and middle triplets 1.3–2.1 and 0.7–1.1 times lengths of primary stalks of dorsal and middle triplets, respectively; primary stalks of dorsal and middle triplets each much longer than secondary stalk; primary stalk of dorsal triplet lying against that of ventral pair at angle of 6 0–70 degrees when viewed laterally; six filaments of dorsal and middle triplets subequal in length (1.8–2.1 mm) and thickness to one another; two filaments of ventral pair subequal in length (2.6–2.7 mm) and thickness to each other, and 1.7 times as thick as six other filaments when compared basally Abdomen. Dorsally, segment 1 with one unbranched slender medium-long hair-like seta on each side; segment 2 with one unbranched slender medium-long hair-like seta and five somewhat spinous minute setae submedially on each side; segment 9 with pair of wide flat terminal hooks, of which outer margin is 3.0 times length of inner margin and crenulated (Fig. 21 L) when viewed caudally. Cocoon (Fig. 21 M). Wall-pocket-shaped, thinly and moderately woven, widely extended ventrolaterally; right submedial portion of anterior margin slightly produced anteriorly; individual threads clearly visible; 3.5 mm long by 2.3 mm wide. Female and larva. Unknown. Type material. HOLOTYPE: Male (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 29, Holotype, Simulium (G.) vinhphucense , Male, coll. Vietnam, 8-XI-2013, Takaoka et al.], reared from a pupa collected from a small stream (width 0.5 m, bottom rocky, water temperature 17˚C, shaded, elevation 975 m, 21˚27’501’’N/105˚38’941’’E), slow-flowing in bushes along the road near the Tam Dao National Park, Vinh Phuc Province, northern Vietnam, 8-XI-2013, by H. Takaoka, M. Sofian-Azirun & Z. Ya’cob. Biological notes. The pupa of this new species was collected from a grass leaf trailing in the current. Associated species were S. (G.) hongthaii, S. (G.) sanchayense sp. nov., S. (N.) sp. (S. feuerborni species-group) and S. (S.) lowi sp. nov. Distribution. Vietnam (Vinh Phuc). Etymology. The species name vinhphucense refers to the province name, Vinh Phuc, where this new species was collected. Remarks. This new species is assigned to the S. asakoae species-group of the subgenus Gomphostilbia by having the yellow hair tuft on the base of the radius and enlarged male hind basitarsi (Fig. 21 B), although the lateral margins of the ventral plate are not emarginated when viewed ventrally (Fig. 21 C). The male of this new species is characterized by the smaller number of upper-eye (large) facets in 9 vertical columns and 11 or 12 horizontal rows. This smaller number of male upper-eye facets was recorded in S. (G.) mengi Chen, Zhang & Wen, and S. (G.) miaolingense Wen & Chen, both described from Guizhou Province, China, which have the male upper-eye facets in eight and nine horizontal rows, respectively (Chen and An 2003). This new species is distinguished from S. (G.) mengi and S. (G.) miaolingense by the larger number of horizontal rows of the male upper-eye facets, from the former species by the stalk of the ventral paired pupal gill filaments as long as or shorter than the common basal stalk (Fig. 21 K) (stalk of the ventral paired filaments longer than the common basal stalk in S. (G.) mengi), and from the latter species by the shape of the ventral plate not angulated laterally (Fig. 21 C) (ventral plate basally angulated outward when viewed ventrally in S. (G.) miaolingense).

Simulium (Simulium) maenoi Takaoka & Choochote, 2002 Simulium (Simulium) maenoi Takaoka & Choochote, 2002: 115 ���120 (Female, male, pupa and larva); Takaoka et al., 2014b: 746 ���747. Distribution. Thailand and Vietnam (Vinh Phuc). Remarks. This species was originally described from Thailand (Takaoka and Choochote 2002). The record from Vietnam was based on three females captured in Tam Dao National Park, Vinh Phuc Province, while flying around a human (Takaoka et al. 2014b). The aquatic stages remain to be collected from Vietnam., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 95, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H. & Choochote, W. (2002) Taxonomic notes on the griseifrons species-group in Simulium (Simulium) (Diptera: Simuliidae) from Thailand: Descriptions of two new species and description of the male, pupa and larva of S. (S.) digrammicum Edwards. Japanese Journal of Tropical Medicine and Hygiene, 30 (2), 115 - 132. https: // doi. org / 10.2149 / tmh 1973.30.115","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, H. T. (2014 b) Female black flies of Simulium (Diptera: Simuliidae) collected on humans in Tam Dao National Park, Vietnam: Description of a new species and notes on four species newly recorded from Vietnam. Tropical Biomedicne, 31 (4), 742 - 748."]}

Simulium (Simulium) atipornae Takaoka, Srisuka & Choochote, 2014 Simulium (Simulium) atipornae Takaoka, Srisuka & Choochote (in Takaoka et al., 2014e): 725���732 (Female, male, pupa and larva); Takaoka et al., 2015a: 60. Distribution. Thailand and Vietnam (Thua Thien Hue). Remarks. Simulium (S.) atipornae was originally described from Thailand and assigned to the Simulium christophersi species-group, defined by Takaoka et al. (2014e). This species was reported based on one pharate male collected from Bach Ma National Park, Thua Thien Hue Province, Vietnam (Takaoka et al. 2015a)., Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on page 90, DOI: 10.5281/zenodo.571608, {"references":["Takaoka, H., Srisuka, W., Otsuka, Y. & Choochote, W. (2014 e) A new species and species-group of Simulium (Simulium) (Diptera: Simuliidae) from Thailand. Journal of Medical Entomology, 51, 725 - 732. https: // doi. org / 10.1603 / ME 13241","Takaoka, H., Sofian-Azirun, M., Ya'cob, Z., Chen, C. D., Lau, K. W. & Pham, X. D. (2015 a) The black flies (Diptera: Simuliidae) from Thua Thien Hue and Lam Dong Provinces, Vietnam. Zootaxa, 3961 (1), 1 - 96."]}

3) Simulium malyschevi species-group Simulium (Simulium) obliquum Takaoka & Low sp. nov. Female. Body length 2.0��� 2.3 mm. Head. Narrower than thorax. Frons black, shiny, with several dark long stout hairs along each lateral margin and few similar hairs just above lower margin; frontal ratio 1.3:1.0:1.0; frons:head ratio 1.0:3.2. Fronto-ocular area well developed, short, directed laterally and slightly upward. Clypeus black, white pruinose, moderately covered with dark long stout hairs along lateral and ventral margins and middle portion of upper two-thirds widely bare. Labrum 0.7 times as long as clypeus. Antenna composed of scape, pedicel and nine flagellomeres, medium to dark brown except scape, pedicel, and flagellomeres 1 and 2 yellow when viewed anteriorly or ventrally, and medium to dark brown except scape and pedicel and base of flagellomere 1 yellow, and rest of flagellomere 1 dark yellow to light brown when viewed posteriorly or dorsally. Maxillary palp with five segments, light brown; proportional lengths of third, fourth, and fifth segments 1.0:1.1:2.0���2.2; third segment (Fig. 44 A) of normal size; sensory vesicle (Fig. 44 A) small, ellipsoidal (0.2 times length of third segment) having moderate opening. Maxillary lacinia with 9���12 inner and 12���14 outer teeth. Mandible with 21���26 inner and 11���13 outer teeth. Cibarium (Fig. 44 B) with blunt median projection bearing several minute tubercles on posterior margin and with three or four minute pointed processes near posterior margin on each side. Thorax. Scutum black, unpatterned, shiny, thinly white pruinose when illuminated at certain angles, moderately covered with dark recumbent minute hairs intermixed with several dark-brown long upright hairs on prescutellar area. Scutellum black, white pruinose when illuminated at certain angles, covered with dark-brown upright long hairs. Postnotum black, white pruinose when illuminated at certain angles, and bare. Pleural membrane bare. Katepisternum black, longer than deep, bare. Legs. Foreleg: coxa whitish yellow; trochanter yellow; femur deep yellow except apical cap medium brown; tibia (Fig. 44 C) white except inner surface of base light brown, and apical cap dark brown, and with large white sheen on outer surface when illuminated at certain angles; tarsus brownish black, with moderate dorsal hair crest; basitarsus greatly dilated, 4.4���4.5 times as long as its greatest width. Midleg: coxa dark brown; trochanter medium brown except base yellowish white; femur medium brown with extreme base somewhat lighter; tibia (Fig. 44 D) medium to dark brown with extreme base and basal one-third of posterior surface yellowish white (its border obliquely defined in lateral view), and with white sheen on posterior surface when illuminated at certain angles; tarsus (Fig. 44 E) yellowish white except apical tip of basitarsus, apical one-third of second tarsomere and most of third tarsomere grayish, fourth tarsomere light brown, and fifth tarsomere medium brown. Hind leg: coxa dark brown; trochanter yellowish white; femur dark brown except base yellowish white and apical cap brownish black; tibia (Fig. 44 F) medium to dark brown except base and little less than basal half of posterior surface yellowish white (its border obliquely defined in lateral view) and apical cap brownish black; tarsus (Fig. 44 G) yellowish white except apical one-fourth or little more of basitarsus medium brown, and apical one-third of second tarsomere and most of third tarsomere grayish, and whole of fourth tarsomere light brown, and fifth tarsomere medium brown; basitarsus (Fig. 44 G) parallel-sided, 6.0���7.2 times as long as wide, and 0.7 and 0.6 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 44 G) developed, small, little shorter than its basal width, and 0.4 times as wide as greatest width of basitarsus; pedisulcus (Fig. 44 G) well developed at basal two-fifths of second tarsomere; claw (Fig. 44 H) with small subbasal tooth. Wing. Length 1.9���2.0 mm. Costa with dark spinules and dull hairs; subcosta bare (except one female with one and two hairs on each subcosta); basal section of radius bare; R1 with dark spinules and hairs; R2 with hairs; hair tuft on base of radium dark brown; basal cell absent. Halter. White except base light brown. Abdomen. Basal scale medium brown, with fringe of dull hairs. Dorsal surface of abdomen medium to dark brown, with short dark hairs; tergite 2 brightly iridescent when illuminated at certain angles, and tergites 6���9 shiny. Ventral surface of segment 7 (Fig. 44 I) with 46���51 branched stout dark hairs medially. Terminalia. Sternite 8 (Fig. 44 J) bare medially, with 8���11 dark medium-long to long stout hairs and three yellow short hairs on each lateral surface. Ovipositor valve (Fig. 44 J) flap-like, bluntly truncate posteriorly, forming oblique roof-like ridge parallel to posterior margin running obliquely, thin, membranous, covered with five to eight dark medium-long or long hairs, one to eight yellow short hairs and numerous microsetae; inner margins not sclerotized, moderately concave medially and widely separated from each other. Genital fork (Fig. 44 K, L) of inverted-Y form, with narrow well sclerotized stem; arms of moderate width, each with distinct projection with rounded apex directed anterodorsally and triangular projection-like sclerotized posteromedial corner. Paraproct in ventral view (Fig. 44 M) triangular, pointed medially, with unpigmented shallow depression on ventral surface along anteromedial margin; anteromedial surface moderately sclerotized and with 6��� 12 sensilla; paraproct in lateral view (Fig. 44 N) 0.6 times as long as wide, with unpigmented shallow depression narrowing ventrally along anteroventral margin, somewhat protruding beyond ventral margin of cercus, and with 10���12 hairs on ventral and lateral surfaces. Cercus in lateral view (Fig. 44 N) short, rounded posteriorly, 0.43 times as long as wide, and with numerous short to medium-long hairs. Spermatheca (Fig. 44 O) large, nearly ovoid, 1.3 times as long as wide, well sclerotized except portion of juncture with duct unsclerotized, with weakly defined surface patterns near base, and with internal setae; accessory ducts subequal in thickness to each other, and to major duct. Male. Body length 2.1���2.3 mm. Head. wider than thorax. Upper eye consisting of large facets in 16���18 vertical columns and in 16���18 horizontal rows. Clypeus brownish black, thickly white pruinose and brightly shiny when illuminated at certain angles, sparsely covered with dark brown hairs along and near lateral margins (most of central portion bare). Antenna composed of scape, pedicel and nine flagellomeres, dark brown to brownish black except scape and pedicel dark yellow, base of first flagellomere yellow, and rest of first flagellomere light brown; first flagellomere elongate, 1.5���1.7 times length of second one. Maxillary palp composed of five segments, light to medium brown except first and second segments grayish yellow; proportional lengths of third, fourth, and fifth segments 1.0:1.2���1.3:2.3; third segment (Fig. 45 A, B) of normal size; sensory vesicle (Fig. 45 A, B) globular or ellipsoidal, 0.1���0.2 times length of third segment, and with small opening. Thorax. Scutum black, with whitish pruinose pattern (brightly iridescent when illuminated at certain angles), i.e., anterior pair of large triangular spots with pointed posteromedial apex on shoulders, narrow band along each lateral margin and large transverse spot entirely covering prescutellar area, all these spots connected; scutum uniformly and moderately covered with brassy recumbent short hairs interspersed with dark-brown long upright hairs on prescutellar area. Scutellum black, with several dark-brown long upright hairs. Postnotum black, whitish pruinose (brilliantly iridescent when illuminated at certain angles) and bare. Pleural membrane bare. Katepisternum brownish black, bare. Legs. Color almost as in female except following characters: Fore tibia (Fig. 45 C) medium brown except median outer surface white and apical cap dark brown. Fore basitarsus greatly dilated, 5.2���5.5 times as long as its greatest width. Mid femur entirely darkened. Mid and hind tibiae dark brown except base yellowish white. Hind basitarsus (Fig.45 D) yellowish white except apical one-third medium brown, and slightly widened toward apical one-fourth, 5.0���5.2 times as long as wide, and 0.7���0.8 and 0.7���0.8 times as wide as greatest widths of hind tibia and femur, respectively; calcipala (Fig. 45 D) developed, small, little shorter than its basal width, and 0.3 times as wide as greatest width of basitarsus; pedisulcus (Fig. 45 D) well developed. Wing. Length 1.6 mm. Other characters as in female including bare subcosta. Halter. White except base light brown. Abdomen. Basal scale brownish-black, with fringe of dark-brown long hairs. Dorsal surface of abdomen dark brown to black, moderately covered with dark-brown short to medium-long hairs; segments 2, 5, 6 and 7 each with pair of whitish pruinose spots (brightly iridescent when illuminated at certain angles) dorsolaterally, those on segment 2 broadly connected in middle to each other. Genitalia. Coxites, styles and ventral plate in ventral view as in Fig. 45 E. Style in ventral view (Fig. 45 E) elongate, with inner margin sinuous, with slender subapical spine; style in ventrolateral view (Fig. 45 F) 1.9 times length of coxite, 2.8 times as long as greatest width near basal one-fourth; style in medial view (Fig. 45 G) flattened dorso-ventrally except basal half gently produced dorsally, which is densely covered with fine short hairs. Ventral plate in ventral view (Fig. 45 E) Y-shaped, with body narrowed posteriorly; arms medium-long and stout, widely separated from each other; ventral plate in lateral view (Fig. 45 H) with body slightly curved ventrally, and with serrated posterior margin; ventral plate in caudal view (Fig. 45 I) with body parallel-sided and rounded ventrally, bare, with four teeth in each of two vertical rows on posterior surface. Median sclerite (Fig. 45 H, J) weakly sclerotized, plate-like, wide, with blunt apical tip having incision medially. Paramere (Fig. 45 K) with wide base having several hooks apically. Aedeagal membrane (Fig. 45 K) moderately covered with minute setae; dorsal plate (Fig. 45 L) horizontal bar-like, weakly sclerotized (except medial portion widely unsclerotized). Abdominal segment 10 (Fig. 45 M, N) without distinct hairs on each side of posterior surface. Cercus (Fig. 45 M, N) small, rounded, with six to eight hairs. Pupa. Body length 2.2���2.4 mm. Head. Integument including antennal sheaths grayish yellow, bare except face sparsely covered with small round tubercles; antennal sheath without any ridges or projections; frons with two pairs of unbranched slender short trichomes arising close together (Fig. 46 A); face with pair of unbranched short trichomes (Fig. 46 B), much longer than frontal trichomes. Thorax. Integument grayish yellow to ochreous, bare on dorsal and dorsolateral surface of anterior half, and sparsely to moderately covered with small tubercles on dorsal, dorsolateral and lateral surfaces of posterior half; thorax on each side with two medium-long trichomes mediodorsally (Fig. 46 C), two trichomes (one medium-long, one short) anterolaterally (Fig. 46 D), one short trichome mediolaterally (Fig. 46 E), and three trichomes (one medium-long, two short) ventrolaterally (Fig. 46 F). Gill (Fig. 46 G) composed of six thread-like short filaments arranged in three pairs (dorsal, middle and ventral) arising from short common basal stalk; each pair short-stalked; all filaments nearly subequal in length (1.0��� 1.5 mm) to one another, though two filaments of ventral pair slightly shorter than others, and inner filament of middle pair slightly longer than outer filament of middle pair; each filament of same thickness (or slightly widened as in outer filaments of middle and ventral pairs) from base to basal one-third, then gradually tapered toward apex; relative thickness of six filaments from dorsal to ventral when measured basally 1.0:0.9���1.1:0.7���1.0:1.1���1.2:0.7��� 0.8:0.8���0.9, inner filament of middle pair thickest and outer filament of ventral pair thinnest; all filaments medium to dark brown, with annular ridges and furrows, densely covered with minute tubercles. Abdomen. Dorsally, segment 1, basal half of segment 2 and narrow portion along anterior margin of segment 3 light brown, other segments transparent except basal areas of spine-combs on segments 7���9 yellow; segment 1 with one unbranched slender short seta (Fig. 46 H) on each side; segment 2 with one unbranched short seta and five minute setae (Fig. 46 I) on each side; segments 3 and 4 each with four distinct unbranched hooks and one unbranched minute seta on each side; segments 5 and 6 lacking spine-combs; segments 7���9 each with distinct spine-combs in transverse row and comb-like groups of minute spines, on each side; segment 9 without terminal hooks. Ventrally, segments 3���9 transparent, each (except segment 9) with comb-like groups of minute spines; segment 4 with few slender minute setae on each side; segment 5 with pair of bifid stout hooks submedially and few unbranched minute setae on each side; segments 6 and 7 each with pair of bifid inner and bifid outer stout hooks somewhat separated from each other, and few unbranched short setae on each side. Grapnel-shaped hooklets absent on each side of segment 9. Cocoon (Fig. 46 J). Simple, wall-pocket-shaped, dull yellowish white, thinly woven, with large anterolateral window (rarely divided into two open spaces) on each side; posterior two-thirds with floor; individual threads invisible; 2.6���3.0 mm long by 1.0��� 1.2 mm wide. Mature larva. Body length 3.5���4.2 mm. Body color creamy with color markings as follows: thoracic segment 1 with grayish-green transverse band though disconnected medioventrally, grayish green on anterior surface of proleg (and usually faintly on posterior surface of proleg) (in three larvae, grayish-green portions mottled with reddish-brown pigment); thoracic segment 2 faintly grayish green on dorsal surface and grayish green mottled with reddish-brown pigment on ventral surface; thoracic segment 3 with faint to moderate reddish-brown transverse band on dorsal and dorsolateral surfaces, and grayish green mottled with reddish-brown pigment on ventral surface; abdominal segments 1���5 each with grayish-green transverse band mottled with reddish-brown pigment, though dorsomedially disconnected; abdominal segments 6���9 grayish green entirely or partially mottled with reddish-brown pigment on dorsal and dorsolateral surfaces and on ventral surface of segments 6 and 7, though dorsomedial portion of segments 7 and 8 often unpigmented; covering of reddish-brown pigment incomplete in some larvae so that one larva entirely light grayish green, and few larvae showing grayish-green ventral surface of abdominal segments 1���5. Head. Cephalic apotome (Fig. 47 A) yellow except posterior half widely darkened medially leaving posterior one of mediolongitudinal spots and posterolateral spots pale, hence making these head spots negative; anterior spot of mediolongitudinal spots and mediolateral spots usually indistinct. Lateral surface of head capsule yellow except eye-spot region whitish and often somewhat darkened between eye-spot region and posterior margin; eyebrow not darkened or slightly darkened; spot below eye-spot region rarely recognized as positive, and large spots in front of posterior margin obscure. Ventral surface of head capsule (Fig. 47 B) yellow except each side of basal portion of postgenal cleft dark brown, and often slightly darkened medially and posteriorly. Antenna composed of three articles and apical sensillum, slightly longer than stem of labral fan; length ratio of three articles (from base to tip) 1.0:1.1:0.8���0.9. Labral fan with 40���42 primary rays. Mandible (Fig. 47 C) with mandibular serration composed of two teeth (one medium-sized, one small); main tooth at obtuse angle against mandible on apical side; supernumerary serrations absent; comb-teeth decreasing in length from first to third. Hypostoma (Fig. 47 D) with nine anterior teeth, of which median and corner teeth subequal in length, and longer than three intermediate teeth on each side; lateral margins sharply serrate apically; four hypostomal bristles in row nearly parallel to lateral border on each side. Postgenal cleft (Fig. 47 B) long, approaching posterior margin of hypostoma leaving narrow postgenal bridge. Thorax and Abdomen. Histoblast of pharate pupal gill with six short filaments. Thoracic and abdominal cuticle with distinct transverse striations and sparsely covered with minute colorless flattened setae and short unbranched colorless setae (Fig. 47 E); abdominal segment 9 with 8���10 short unbranched colorless setae on each side of anal sclerite; thoracic segment 3 with two small protuberances (one dorsally and one dorsolaterally) on each side; abdominal segments 1���4 each with six small protuberances (one dorsally, one dorsolaterally, two laterally, one ventrolaterally, and one ventrally) on each side; abdominal segment 5 with four small protuberances (one dorsally, one dorsolaterally, two laterally), abdominal segment 6 with three small protuberances (one dorsally, one dorsolaterally and one laterally) on each side; abdominal segment 7 with two small protuberances (one dorsally and one dorsolaterally) on each side; abdominal segment 8 with one small protuberance dorsally on each side; all protuberances cone-shaped except ventral ones rounded (Fig. 47 F). Rectal scales present. Rectal organ compound, each lobe with 9 or 10 finger-like secondary lobules. Anal sclerite Xshaped, widely sclerotized basally, with short broad anterior arms 0.7 times as long as posterior ones, and four to eight sensilla posterior to posterior arms. Last abdominal segment bulged ventrolaterally but lacking ventral papillae. Posterior circlet with 70���74 rows of hooklets with up to 13 or 14 hooklets per row. Type material. HOLOTYPE: Female (with its associated pupal exuviae and cocoon) in 80% ethanol, labeled in a vial as [UMSRP: Vietnam 0 37, Holotype, Simulium (S.) obliquum , Female, coll. Vietnam, 9-XII-2015, Takaoka et al.], reared from pupa collected from a river (width 8���10 m, flow moderate, bottom of pebbles, water temperature 17˚C, exposed to the sun, elevation 162 m, 18˚58���45.918���N/109˚50���10.693���E), fast flowing in a natural forest, Pu Mat, Nghe An Province, northern Vietnam, 9-XII-2015, H. Takaoka, M. Sofian-Azirun, C.D. Chen, & K.W. Lau. PARATYPES: 15 females and 15 males, with their associated pupal exuviae and cocoons, and 10 mature larvae, in 80% ethanol, same data as those of the holotype labeled in each vial as [UMSRP: Vietnam 0 37, Paratype, Simulium (S.) obliquum , Female, coll. Vietnam, 9-XII-2015, Takaoka et al.]. Biological notes. The pupae and larvae of S. (S.) obliquum sp. nov. were collected from grasses trailing in the current. Associated species were S. (S.) tani (complex) and S. (S.) sp. (S. striatum species-group). Distribution, Published as part of Takaoka, Hiroyuki, Sofian-Azirun, Mohd, Ya'Cob, Zubaidah, Chen, Chee Dhang, Lau, Koon Weng, Low, Van Lun, Pham, Xuan Da & Adler, Peter H., 2017, The black flies (Diptera: Simuliidae) of Vietnam, pp. 1-165 in Zootaxa 4261 (1) on pages 101-108, DOI: 10.5281/zenodo.571608, {"references":["Rubtsov, I. A. (1956) Blackflies (Simuliidae). Fauna of the USSR. 2 nd Edition. No. 61, Diptera 6 (6). Acad. Nauk SSSR, Moscow and Leningrad, 859 + [1] pp. [translated from Russian by Amrind Publ. Co. Pot. Ltd., Delhi, India, 1989]","Takaoka, H. & Saito, K. (1996) A new species and new records of black flies (Diptera: Simuliidae) from Thailand. Japanese Journal of Tropical Medicine and Hygiene, 24 (3), 163 - 169.","Takaoka, H. & Mulla, M. S. (2000) Taxonomic notes on Simulium siripoomense from Thailand (Diptera: Simuliidae): descriptions of female and pupa, and change of its subgeneric status from Byssodon to Simulium s. str. Japanese Journal of Tropical Medicine and Hygiene, 28 (1), 25 - 28.","Puri, I. M. (1932 c) Studies on Indian Simuliidae. Part IV. Descriptions of two new species from North-East India Simulium howletti sp. n. and Simulium hirtipannus sp. n., with a note on S. ornatum Meigen. Indian Journal of Medical Research, 20, 505 - 514."]}