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Bibio sp. (Fig. 1) Material. Specimen MNT Nel 1171 (part and counterpart of an adult fly with apex of abdomen missing), deposited in the “Musée de Paléontologie de Menat”¸ Menat, Puy-de-Dôme, France. Type locality and horizon. New quarry, Menat, Puy-de-Dôme, France; middle Paleocene, Menat Basin. Description. Total body length 8.2 mm. Head length 0.9 mm, width 1.1 mm. Palp small, brown. Antenna very short, 0.7 mm long, brown, with eight (?) flagellomeres. Ocellar tubercle not very prominent. Thorax: mesonotum 2.4 mm long, black, with sparse setation poorly preserved; haltere not preserved. Fore tibia with a strong spur and a strong anterior projection, spur almost as long as anterior projection. Protarsus slender. Mid legs not preserved. Hind femur 2.4 mm long, 0.6 mm wide, tibia 1.8 mm long, 0.2 mm wide, tarsus not preserved. Wing ca. 4.9 mm long, 2.0 mm wide, light brown infuscate, stigma dark brown; visible veins brown, bare, R-veins thickened. C not extending beyond apex of Rs. Rs nearly reaching wing apex, with its basal part 0.4 mm long; R1 ending on C at 3.3 mm of wing base; Rs and M touching in one point. Branches of M, cubital and anal veins extremely faint, hardly visible. Abdomen brown, narrow, slightly elongate (possibly a male), preserved part 3.9 mm long, 1.3 mm wide. Terminalia not preserved., Published as part of NEL, ANDRÉ & KUNDURA, JEAN-PAUL, 2023, The oldest Bibio Geoffroy, 1762 (Diptera: Bibionidae) from the Paleocene of Menat (France), pp. 226-229 in Palaeoentomology 6 (3) on pages 227-228, DOI: 10.11646/palaeoentomology.6.3.3, http://zenodo.org/record/8073024

Four new Neotropical species of Plecia Wiedemann (Diptera: Bibionidae) are described: P. abruptavena sp. n. (Colombia), P. elsalvadorensis sp. n. (El Salvador), P. nessiae sp. n. (Brazil), and P. schusteri sp. n. (Guatemala). Additionally, P. marginata Edwards is redescribed and the male described for the first time. A discussion of Neotropical species-groups is given and three species-groups based on male terminalia are outlined to include the new taxa: the americana-group (7 species), nigra-group (13 species), and xyele-group (2 species).

Dilophus cerestensis sp. nov. is the first described species of this bibionid genus from the lower Oligocene of Céreste (France). The species is characterized by a wing with the crossvein r-m quite shorter than basal part of Rs, a putative symplesiomorphy for this genus, suggesting a position in its stem group. Dilophus is significantly less diverse and frequent in the fossil record (mainly from the Northern Hemisphere) than the other bibionid genera Bibio, Plecia, and Penthetria, possibly related to a Gondwanan origin.

Dilophus cerestensis sp. nov. (Figs 1–3) urn:lsid:zoobank.org:act: 9B06E4BA-CE35-4FC7-B71AF56D20F3D561 Material. Holotype specimen PNRL 2243 (Coll. Nel, imprint of a complete fly fossilized in dorsal view, male), stored in the Musée of Palaeontology, Réserve Géologique du Lubéron, Apt, France. Etymology. Named after the type locality Céreste. Diagnosis. Wing crossvein r-m quite shorter than basal part of Rs; posterior margin of sternum 9 without emargination on each side of broad median one; tergum 9 with an obtuse angled V-shaped posterior emargination; harpagones very broad, nearly right-angled in middle and narrowing gradually towards conical acute apex. Type locality and horizon. South of the village of Céreste, Alpes-de-Haute-Provence, France, Early Oligocene, ‘ Calcaire de Campagne-Calavon’ Formation. Description. Total body length 8.0 mm. Head black, with long setae visible laterally, 1.3 mm long, 1.1 mm wide; compound eyes 0.2 mm long, situated in anterior half of head; occiput elongate; right maxillary palp visible, with third palpomere larger than others; antenna short and stocky, 11 antennomeres. Thorax 2.2 mm long, 1.2 mm wide; mesonotum black, with at least two frontal spines and two in more posterior positions. Wing hyaline, 5.8 mm long, ca. 1.6 mm wide; pterostigma small, oval and dark brown, R-veins dark brown, vein M colorless; Costa extending to apex of R 4+5; crossvein r-m 0.1 mm long, quite shorter than basal part of Rs (0.3 mm long); distal parts of vein M and posterior half of wing not visible. Halters not visible. Legs yellowish-brown, without discernible pilosity, tarsi black; fore femur strong, 1.4 mm long, tibia rather stout, 0.9 mm long, with an oblique median row of two-three spines and an apical row of three spines, tarsus 2.9 mm long; mid femur ca. 1 mm long, mid tibia 1.2 mm long, tarsus 2.0 mm long; hind femur 2.4 mm long, dilated distally, tibia 2.1 mm long, strongly dilated distally, tarsus 2.2 mm long, basal tarsomere enlarged, nearly as wide as tibia. Abdomen cylindrical, dark brown, 4.0 mm, 1.0 mm wide, covered with a light, rather long, sparse pilosity, visible laterally. Hypopygium: posterior margin of sternum 9 without emargination on each side of broad median one; tergum 9 with an obtuse angled Vshaped posterior emargination. Harpagones very broad, nearly right-angled in middle and narrowing gradually towards conical acute apex., Published as part of NEL, ANDRÉ, LEGAL, STÉPHANE & COSTER, PAULINE, 2022, A new species of the March fly genus Dilophus Meigen, 1803 (Diptera: Bibionidae) from the Oligocene of Provence (France), pp. 347-353 in Palaeoentomology 5 (4) on pages 348-349, DOI: 10.11646/palaeoentomology.5.4.7, http://zenodo.org/record/7333540

We describe Cretobibio montsecensis, gen. et sp. nov. based on two female specimens from the Lower Cretaceous of Montsec, Spain. The new genus would key to the subfamily Pleciinae based on the presence of a short vein R2+3 and slender legs. However, some characters suggest an affinity with Bibioninae, notably the weakening of R2+3, the oblique crossvein R-M, crossvein M-Cu connected to M2 rather than the stem of M, and the shortened fore legs. We suggest this species is best considered as representing a new subfamily, Cretobibioninae subfam. nov., as sister group of Bibioninae.

Cretobibio rasnitsyni sp. nov. (Fig. 1) Material. Holotype, male. CCNH-139, housed at Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo, Brazil. Etymology. The species epithet honors Prof A.P. Rasnitsyn, an eminent Russian paleontologist, for all his collaboration in the study of insect fossils worldwide. Diagnosis. Wing with extremely short distal section of M 3+4. Locality and horizon. Crato Formation. Brazil, Ceará, Nova Olinda (07°05′30ʺ S, 39°40′46ʺ W), Pedreira Três Irmãos; upper Aptian, Lower Cretaceous. Description. Male. Small, total length, 4.4; thorax length, 1.4; wing length, 3.9; wing maximal width, 1.1; abdomen length, 2.8. Head. Head height smaller than thorax height. Antenna short, flagellomeres not discernible. Thorax. Scutum short, arched. Legs. Tibial spurs not discernible. Tarsi short. Wing. C ending beyond tip of R 5, close to wing apex; Sc ending just beyond midwing. Pterostigma large, pale brown. R 1 and R 4+5 strong, R 1 ending in C level with M 1+2 furcation. Basal section of Rs oblique, long, 4x longer than r -m. Slightly curved R 4+5 forked clearly distal to tip of R 1, reaching margin before wing apex; R 5 3.7x longer than short R 4, R 5 ending in C level with M 2 tip, slightly curved. Stem M more sclerotized basally to insertion of r -m, weaker more distally. M 1+2 fork narrow, 1.4x longer than R fork and 5x longer than distal section of M 3+4. Basal section of M 3+4 gently arched, level with tip of R 1, near to M 1+2 furcation; m -cu very long, 3.5x longer than distal section of M 3+4. Not possible to recognize microtrichia on wing membrane. Terminalia. Hypopygium poorly preserved, compact, gonocoxite massive, gonostylus well-developed, short, slightly elongate, probably digitiform (only apex visible). 4+5 Remarks. The new species differs from the type species in extremely short distal section of M 3+4 which is subequal to m -cu in C. montsecensis. Wing of C. rasnitsyni sp. nov. male is larger than in type species, based on female (3.9 instead of 3.0–3.2) although usually females are larger.

A checklist is presented of all 986 extant species of Diptera known from the archipelago of the Maltese Islands situated in the central Mediterranean. Species considered to be alien to the Islands are listed with annotations in Appendix 1. The history of dipterology applicable to the islands is outlined and the three important historical published records by Zetterstedt, Rondani and Bezzi & de Stefani-Perez are listed in Appendices 2–4. Species names that are synonyms are indicated where these were used in published records for Malta more or less after the Catalogue of Palaearctic Diptera was published. Species we consider to have been misidentifications are also indicated with an annotation in most cases. Vermileo immaculatus Carles-Tolrá syn. n. & Cuesta-Segura and Vermileo balearicus Wheeler syn. n. are proposed junior synonyms of Vermileo vermileo (Linnaeus).

Plecia schusteri Fitzgerald sp. n. (Figs. 24–30) Type Material. Holotype: Male, point-pinned (CNCI), “ GUATEMALA, Guatemala, Puerta Parada, 1840 m, 27 X–3 XI 2018, Col.: J.C. Schuster ” [white label]. HOLOTYPE, Plecia schusteri Fitzgerald [red label], terminalia dissected. Description. Holotype Male. General coloration. Entirely black to very dark brown, except mesonotum mostly orange, but blackened anteromedially. Head. Three ocelli on tubercle. Antenna dark brown with seven bead-like flagellomeres, apical flagellomere minute, nipple-like. Compound eye holoptic with minute sparse ommatrichia, divided into upper and lower section of larger and smaller facets by slight depression. Face not produced anteriorly. Clypeus rectangular, about twice as long as wide. Clypeus + proboscis short, subequal to length of antennae. Palps brown, five-segmented. Thorax. Mesonotum with a subtle median and a pair of more distinctive dorsocentral grooves. Mesonotum largely bare with short dark sparse setae in median and dorsocentral grooves as well as laterally; much more numerous anteriorly. Katepisternum with patch of dorsal setae, anepimeron and metakatepisternum with a few setae. Legs. Slender, dark brown with dense short dark setae. Hind tibia nearly parallel-sided. Hind basitarsus long, slender, parallel-sided, approximately seven times as long as wide. Wing. About 7.0 mm, light brown fumose, darker anteriorly. All veins brown, anterior veins bolder, pterostigma dark brown and darker than the membrane. R 2+3 short, evenly curved, strongly divergent from R 4+5, ending in C. Abdomen. With short dark hair. Terminalia (Figs. 25–30). Epandrium (tergite nine) rectangular, broader than long, nearly truncate posteriorly with a minute narrow median notch, though tergite is creased medially along entire length. Epandrium without posteromedian lobe or flap visible in dorsal view, but with a median keel on ventral surface visible in posterolateral view (Fig. 28). Epandrial lobes apically rather truncate. Anterior margin of epandrium with slight broadly U-shaped excavation. Gonocoxites ventrally broader than long, with deep broad U-shaped posteromedian cleft; sclerotized median projection absent, but bottom of cleft broadly sloping into genital chamber and large membranous hump which can been seen in both posterior and ventral views. Lateral lobes of gonocoxites present, in ventral view inner (medial) surface sloping into genital chamber, in posterolateral view lobes broadly triangular though apically rounded. Gonostylus minute, in ventral view, pear-shaped (Fig. 25), in posterior view rounded basally with a distinct thumb-like apical projection (Fig. 29), and in posterolateral view rounded basally with a small thumb-like projection appearing much shorter than in posterior view (Fig. 30). Female. Unknown. Diagnosis & Remarks. This species is most similar to P. americana Hardy and P. evansi Fitzgerald, but can be distinguished most easily by color differences: P. americana with thorax entirely orange (sometimes with some brown markings on thoracic pleurae), P. evansi with thorax entirely black, and P. schusteri with scutum black anteriorly and orange posteriorly, scutellum orange, thoracic pleurae and postnotum black. The male terminalia of these three species are very similar; all have strongly reduced gonostyli, gonocoxites with ventral posteromedian margin deeply cleft, posteromedian margin of epandrium with only small cleft, and lateral lobe of gonocoxites present with medial (inner surface) sloping into the genital chamber. P. evansi has a very broad, shallow, V-shaped epandrial cleft (cleft about ¼ depth of sclerite) with a small median lobe, while P. schusteri has only a narrow notch posteromedially. The terminalia of P. americana and P. schusteri differ most in the shape of the gonostylus; in posterior view, the gonostylus of P. americana is triangular apically while there is a distinct thumb-like apical development in P. schusteri (compare Figs. 29 & 31) and in posterolateral view the apex of the gonostylus of P. americana is very short and slightly hooked whereas that of P. schusteri is longer and more digitate (compare Figs. 30 & 32). P. schusteri belongs to the americana -species-group (see Discussion) and will key to couplet 28 using Hardy’s 1945 key. Etymology. The specific epithet honors Dr. Jack Schuster (UVGC), collector of the holotype as well as the type series of several other recently described Guatemalan Diptera such as Amerikeroplatus dimorphicus Fitzgerald (Keroplatidae) and Ditomyia nana Fitzgerald (Ditomyiidae). Distribution. Known only from the holotype collected in Guatemala., Published as part of Fitzgerald, Scott J., 2021, New species of Neotropical Plecia Wiedemann (Diptera: Bibionidae) and delineation of the americana-, nigra-, and xyele- species-groups, pp. 21-40 in Zootaxa 5005 (1) on pages 33-36, DOI: 10.11646/zootaxa.5005.1.2, http://zenodo.org/record/5141077, {"references":["Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547."]}

Plecia elsalvadorensis Fitzgerald sp. n. (Figs. 6–9) Type Material. Holotype: Male, point-pinned (USNM), “ EL SALVADOR, Monte Cristo, 7–9 May 1958, OL Cartwright” [white label]. USNMENT 01556013 [white data matrix label]. HOLOTYPE, Plecia elsalvadorensis Fitzgerald [red label]. Paratypes: same as holotype except: USNMENT 01556014, 01556011, & 01556012, 3 males (2 USNM, 1 SFC). Description. Male (Fig. 6). General coloration. Scutum and scutellum matte orange, thoracic pleurae light brown with orange tint to orange with brownish tint. Abdomen and legs dark brown. Head black. Wings brown fumose. Head. Three ocelli. Antennae brown with apex of pedicel and base of flagellomere one with orange tint. Antenna with seven bead-like flagellomeres with short dark setae, basal flagellomere about twice as long as broad, apical flagellomere round, minute. Compound eye holoptic with minute sparse ommatrichia, divided into upper and lower section of larger and smaller facets by slight depression. Face not produced anteriorly. Mouthparts not elongated, clypeus + proboscis shorter than antennae; clypeus rectangular, broader than long. Maxillary palps apparently with only four segments (five is typical, but as these are very shriveled and difficult to count it is possible a fifth palpomere is present). Face, clypeus, and palps with short dark setae. Thorax. Mesonotum matte with a subtle median and a pair of more distinctive dorsocentral grooves. Mesonotum largely bare with short dark sparse setae in median and dorsocentral grooves as well as laterally. Thoracic pleurae bare except katepisternum with patch of dorsal setae. Legs. Legs slender, long, with dense short dark setae. Hind femur only slightly clavate distally. Hind tibia slender, parallel-sided. Hind basitarsus slender, parallel-sided, approximately six times as long as wide. Wing. 6.5 mm, brown fumose. Veins brown, anterior veins darker and bolder. Venation typical for the genus (Fig. 6). R 2+3 short, curved (bent most strongly at midpoint), strongly divergent from R 4+5, ending in C. Pterostigma present but nearly concolorous with wing membrane. Halters dark brown, base of stem tinted with orange. Abdomen. With short dark hair. Terminalia (Figs. 7–9). Epandrium (tergite nine) posteromedially with deep, broad, V-shaped cleft extending about ½ length of sclerite, median projection absent. Epandrium long (almost as long as broad), extending beyond apex of lateral lobe of gonocoxite, epandrial lobes somewhat triangular. Anteromedial edge of epandrium with a shallow broad V-shaped cleft. Gonocoxites ventrally with V-shaped posteromedial cleft which includes a small step about 1/3 from anterior end of cleft. In ventral view, a broad median membranous hump present immediately dorsal to posteromedial cleft of gonocoxites. Lateral lobes of gonocoxites laterally flattened, flap-like, apically rounded, extending well beyond gonostylus. Gonostylus minute, droplet-shaped; subspherical in ventral view, but in posterolateral view strongly tapered to slightly hooked point. Female. Unknown. Diagnosis & Remarks. This species is most similar to P. americana Hardy but differs in the shape of the epandrium; posteromedially deeply cleft with triangular lobes in P. elsalvadorensis versus with a minute V-shaped cleft and truncate lobes in P. americana. The epandrium in P. elsalvadorensis is almost as long as broad whereas it is distinctly broader than long in P. americana. Additionally, the lateral lobes of the gonocoxites are longer in P. elsalvadorensis (extending well beyond the gonostylus in ventral view) whereas in P. americana they are very short (apex of the lateral lobe of the gonocoxite barely extending beyond gonostylus in ventral view). P. elsalvadorensis is also quite similar to P. parvistylata Hardy but differs by the lateral lobes of the gonocoxite not developed into apical knobs, epandrium without a median projection, and shape of the posteromedian cleft of gonocoxites; stair-step-Vshaped rather than gently rounded. P. elsalvadorensis belongs to the americana -species-group (see Discussion). Using Hardy’s 1945 key it is not possible to get beyond couplet 1 with this species since the thoracic pleurae are neither black as in couplet 1a nor concolorous with the dorsum as in couplet 1b, but are orange tinged with brown while dorsum is entirely orange. Etymology. The specific epithet is from the type locality El Salvador. Distribution. Known only from the type series collected in El Salvador., Published as part of Fitzgerald, Scott J., 2021, New species of Neotropical Plecia Wiedemann (Diptera: Bibionidae) and delineation of the americana-, nigra-, and xyele- species-groups, pp. 21-40 in Zootaxa 5005 (1) on pages 25-26, DOI: 10.11646/zootaxa.5005.1.2, http://zenodo.org/record/5141077, {"references":["Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547."]}

Plecia abruptavena Fitzgerald sp. n. (Figs. 1–5) Type Material. Holotype: Male, point-pinned (USNM), “ COLOMBIA, Capueta, pass at Gabineta, 2 Sept. 1969, D.H. Messersmith ” [white label]. 11E [white label]. USNMENT 01556010 [white data matrix label]. HOLOTYPE, Plecia abruptavena Fitzgerald [red label], terminalia dissected. Description. Holotype Male (Fig. 1). General coloration. Entirely black. Thorax dark matte velvet black with abdomen slightly lighter blackish-dark brown. Legs slightly shiny black. Head. Three ocelli on tubercle. Antenna with eight black, bead-like flagellomeres with short dark setae, basal flagellomere about twice as long as broad, apical flagellomere round, minute. Compound eye holoptic with minute sparse ommatrichia, divided into upper and lower section of larger and smaller facets by slight depression. Face not produced anteriorly. Mouthparts not elongated, clypeus + proboscis shorter than antennae; clypeus rectangular, about twice as long as wide. Face, clypeus, and 5-segmented palps with short dark setae. Thorax. Mesonotum matte with a subtle median and a pair of more distinctive dorsocentral grooves. Mesonotum largely bare with short dark sparse setae in median and dorsocentral grooves as well as laterally. Thoracic pleurae bare except katepisternum with patch of dorsal setae and anepisternum with a few small dorsal setae. Legs. Missing middle legs. Remaining legs slender, long, with dense short dark setae. Hind femur only slightly clavate distally. Hind tibia slender, parallel-sided. Hind basitarsus slender, parallel-sided, approximately six times as long as wide. Wing (Fig. 2). 9.5 mm, dark brownish fumose, darker anteriorly. Anterior veins dark brown, except basal half of M before r-m, remainder of M fork just beyond r-m, most of M 4, CuA, and CuP unpigmented (concolorous with wing membrane). A 1 dark brown, short, terminating even with crotch of anal lobe of wing. Pterostigma dark brown. R 2+3 short, curved (bent most strongly at midpoint), strongly divergent from R 4+5, ending in C. Halters blackish. Abdomen. With short dark hair. Terminalia (Figs. 3–5). Epandrium (tergite nine) posteromedially with deep, broad, U-shaped cleft; bottom (anterior end of cleft) with a short, broad, shining, shelflike, posteroventrally-directed flap. Apex of epandrial lobes apically broadly rounded in dorsal view. Anterior edge of epandrium with a deep broad U-shaped cleft leaving most of the median area of epandrium (anterior to posteromedian cleft) membranous, so that sclerite is nearly divided medially. Gonocoxites ventrally continuous without a median projection, but with a pair of very small rounded setose submedian lobes forming part of the socket of the gonostyli (a small v-shaped notch present inbetween these two lobes but extending only about as deep as the bottom of the gonostylar socket). In ventral view, lateral lobes of gonocoxites taller than gonostyli, slender, with patch of dense setae on medial surface; lobes apically rounded in lateral view. In ventral view, gonostylus somewhat dagger-like, smooth, shinning, tapering apically, with a broad basolateral lobe bearing a patch of short minute hairs on outer edge. Gonostylus somewhat dorsoventrally flattened (best seen in dorsal view), but slightly tilted medially so that in posterolateral view the nearer gonostylus can be seen to be flat beyond the basolateral lobe while the farther gonostylus appears broad throughout (compare gonostyli in Fig. 5). In posterolateral view, very apex of gonostylus digitate and minutely hooked. Female. Unknown. Diagnosis & Remarks. This species is most similar to P. imperialis Schiner from Venezuela (Hardy 1967), but is distinguished by the form of the gonostylus; in P. abruptavena the gonostylus has a basal lobe on the outer edge with the inner edge straight, whereas the gonostylus of P. imperialis is symmetrical; gonostylus bulbous at the base and distinctly constricted into the digitate apical portion (Hardy 1945, fig. 145a). P. abruptavena is also similar to P. apoxys Fitzgerald from Peru (Fitzgerald 1998), but can be distinguished by the shape of the gonostylus; dorsoventrally flattened, tapered to a digitate, slightly hooked apex in P. abruptavena and laterally compressed, more gradually and evenly hooking apically and with an acute apex in P. apoxys. P. abruptavena belongs to the nigra - species-group (see Discussion) and will key to couplet 24 in Hardy’s 1945 key. Etymology. The specific epithet is from the Latin abruptus (broken off) and vena (vein) for the odd wing venation of this species which has portions of some veins which abruptly change from strong and distinctly pigmented to thin and hyaline. Distribution. Known only from the holotype collected in Colombia., Published as part of Fitzgerald, Scott J., 2021, New species of Neotropical Plecia Wiedemann (Diptera: Bibionidae) and delineation of the americana-, nigra-, and xyele- species-groups, pp. 21-40 in Zootaxa 5005 (1) on pages 22-25, DOI: 10.11646/zootaxa.5005.1.2, http://zenodo.org/record/5141077, {"references":["Hardy, D. E. (1967) The types of Bibionidae (Diptera) in the Naturhistorisches Museum, Wien. Annalen des Naturhistorisches Museum in Wien, 70, 169 - 181.","Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547.","Fitzgerald, S. J. (1998) Eighteen new species of Neotropical Plecia (Diptera: Bibionidae) and taxonomic notes on the genus. Transactions of the Entomological Society of America, 124 (2), 133 - 164."]}

Plecia marginata Edwards, 1920 (Figs. 10–17) Type Material. Holotype female: “Museum Paris, Équateur, Tulcan, Dr. G. Rivet, 1901.” (MNHN). Paratypes: topotypic, 2 females (1 MNHN, 1 BMNH), (all examined in 1998). Additional material examined. COLOMBIA: “ Cauca, Paramo de Parace, Lake San Rafael, 3570 m, 29.I.59, J. F. G. Clarke,” 1 female (USNM); “Valle Tenerife, paramo at 12,000’, R.E. Dietz, 15 Sept. 1970,” 1 male (USNM). Discussion. Edwards (1920) described Plecia marginata from three female specimens collected on the northern border of Ecuador at high elevation (“ Équateur. Tulcan, alt.: 3200m ”). Since then, no additional specimens have been reported and Hardy’s 1945 revision of the New World Plecia simply provides an English translation of the original description and states that “the writer has not seen this species.” Species concepts in the genus Plecia rely heavily on characters of the male terminalia and many females are unknown, unassociated with males, or undescribed, making most unassociated females unidentifiable. However, the female of P. marginata has several features that make it somewhat distinctive. Firstly, is its’ very large size; Edwards (1920) states that the female wing is 11–13 mm (the present author’s measurements of the wings of the types is 10.5–12.0 mm), making it one of the largest species of New World Plecia. Secondly, is the dull black mesonotum with a narrow but continuous orange border; this color combination is very unusual and Hardy (1945) notes that the species “should be easily recognized by the orange border on the mesonotum and the reddish pleurae and abdomen.” During a visit to MNHN and BMNH in 1998 I had the opportunity to study the holotype (redescribed below) and paratypes of P. marginata and confirm both its large size and unique color combination. During routine determinations of unsorted material from USNM, two specimens (one male and one female) from two high elevation (páramo) sites in Colombia were discovered that fit the description of this species. The female (Figs. 10–12), collected about 204 km northwest of the type locality, matches the original description and my notes on the type series very well except that the abdomen is brown rather than reddish-brown and the wings are longer; wing length of this female is 14.5 mm, which is very large for this genus (nearly the known upper limit for the New World species). The male specimen (Fig. 13) (exact locality difficult to discern from label data) largely matches the female in structure and color except vein R 2 +3 shorter and more divergent from R 4 +5 and the dark central area of the mesonotum is more brownish-black in color and subtly divided into broad stripes. The male is also smaller (wing 11.0 mm) than the Colombian female but falls within the wing length range of the type series and, in any case, males are usually smaller than females. Additionally, the male terminalia do not match any other known species suggesting it is either a new species or belongs to a species (e.g., P. marginata) for which the male is unknown. Based on the original description, as well as my notes from study of the type series, the female from Colombia appears to be conspecific with P. marginata. Whether the male and female specimens from Colombia are conspecific with each other cannot be confirmed, but the unique color combination and otherwise largely matching descriptions suggests they are conspecific; they differ most in the length and angle of R 2+3 (shorter and more divergent from R 4+ 5 in male), though this may just be intraspecific variation as this vein shows considerable intraspecific variation in the similar bibionid genus Penthetria (Fitzgerald 2021). Based on these considerations, the male is tentatively treated here as P. marginata and used to provide the first description of the male. Redescription. Female (redescription based largely on notes from examination of holotype and paratypes in 1998 with additions, based on female from Colombia, given in braces {}): Coloration. Head black. Pedicel and base of first antennal segment orange, remaining segments brown {to dark brown}. Scutum primarily matte dark brown to black with thin grey pruinosity. Lateral margins of scutum narrowly orange, humeral ridge orange, and scutellum orange with thin brown median stripe. Thoracic pleurae brown tinged with orange (becoming more orange ventrally), {postnotum orange}. Legs yellow-brown with apices of femora, tibiae and basal tarsal segments brown, distal tarsomeres entirely brown. Halter with base of stem orange, apical ½ of stem and knob brown {to very light brown}. Wing hyaline {to very slightly greyish}, veins light brown {to orangish}, anteriors more strongly pigmented. Stigma light brown {to brown}. Abdomen orange-brown {to dark brown}. Head. Rather wide, three ocelli and tubercle present. Median line of frons somewhat carinate with two small round tubercles; ridge extending about half-way from antennal base to ocellar tubercle. Median ridge of frons strongly developed in one of the paratypes (MNHN). Face scarcely developed; produced about width of one flagellomere length beyond antennal base. Clypeus + proboscis black, broad, short, {about as long as long axis of eye}. Nine flagellomeres, apical flagellomere minute nipple-like. Thorax. Katepisternum with a patch of setae. Legs. Hind tibia slender, hind basitarsus slender, long, about eight times as long as wide (twelve times as long as wide in BMNH paratype). Legs with short dark hair. Wing. Wings seem disproportionally long for the body size. Wing 10.5–12.0 mm, {14.5 mm}. R 2 +3 1/3 length R 4 +5, r-m ¼ length stem of M fork. {Venation typical for the genus (Fig. 12)}. Terminalia. Tergite nine much broader than long, with a short triangular median point on posterior edge. Description. Male. Coloration. Head black. Apex of pedicel and very base of first antennal segment orangish, remaining segments dark brown. Scutum matte orange in ground color with three broad, matte, light brown stripes which are nearly contiguous with each other; very thinly separated by orange tint along dorsocentral grooves and median stripe medially longitudinally subdivided by thin orange line in median groove. Scutum with, lateral areas, humeral ridge, area just posterior to humeral ridge, scutellum, and area just anterior to scutellum orange. Thoracic pleurae largely orange except light brown dorsally. Legs yellowish with extreme apices of femora, tibiae (very subtly so) and basal tarsal segments light brown, distal tarsomeres entirely brown. Legs with dark hairs. Halter with base of stem orange, apical ½ of stem and knob brown. Wing hyaline to very light greyish, veins light brown, anteriors more strongly pigmented. Pterostigma light brown. Abdomen dark brown with pale hairs. Head. Three ocelli and tubercle present. Eye holoptic. Face not produced. Clypeus rectangular, about twice as long as wide. Clypeus + proboscis black, broad, short. Antennae with eight or nine flagellomeres (difficult to count as antennae are strongly shriveled), apical flagellomere minute nipple-like (at least on one antenna). Palps with four or five segmented (shriveled and hard to determine). Thorax. Mesonotum largely bare with short, very sparse, pale setae near subtle median and deeper dorsocentral grooves as well as laterally. Katepisternum with patch of dorsal setae. Legs. Long and slender, hind tibia and basitarsus nearly parallel-sided. Hind basitarsus about eight times as long as wide. Wing. 11.0 mm. R 2+3 1/4 length R 4+5. Venation typical for the genus (Fig. 13). Abdomen. Terminalia (Figs. 14–17). Epandrium (tergite nine) short, distinctly broader than long, posteromedial cleft broadly V-shaped with a small median triangular lobe, main posterior lobes of epandrium somewhat triangular but apically rounded. Anteromedial cleft of epandrium broad, U-shaped, extending about 1/3 length of sclerite. Gonocoxites ventrally broader than long, lacking posteromedian cleft and sclerotized median projection, though a pair of small rounded, setose, submedian lobes present that form part of the gonostylar socket. Lateral lobes of gonocoxites present, broad and broadly rounded apically in posterolateral view. Gonostylus simple, long digitate, slightly arched and gradually tapering apically to an acute point; posterior surface of gonostylus laterally compressed, fin-like, so that gonostylus appears much more robust (seagull-head-shaped) in posterolateral view than posterior view and appears acute in ventral and dorsal views (when fin is being view head-on). Diagnosis & Remarks. The unique color of the mesonotum (dark medially with continuous orange border) and large size makes this species distinctive, but the shape of the gonostylus will distinguish it from other species, such as P. boliviana Fitzgerald, with similar terminalia. P. marginata belongs to the nigra -species-group (see Discussion). Distribution. Previously known only from a high elevation type locality near the Ecuador / Colombia border. Newly reported specimens are from high elevation (páramo) sites in Colombia., Published as part of Fitzgerald, Scott J., 2021, New species of Neotropical Plecia Wiedemann (Diptera: Bibionidae) and delineation of the americana-, nigra-, and xyele- species-groups, pp. 21-40 in Zootaxa 5005 (1) on pages 28-31, DOI: 10.11646/zootaxa.5005.1.2, http://zenodo.org/record/5141077, {"references":["Edwards, F. W. (1920) Dipteres Nematoceres. Mission du Service Geographique de L'Armee pur la mesure d'un Arc de Meridien Equatorial en Amerique du sud sous le controle scientifique de l'academie des sciences 1899 - 1906, 10 (2), 147 - 149.","Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547.","Fitzgerald, S. J. (2021) Penthetria Meigen (Diptera: Bibionidae): Revision of New World species and world catalog. Zootaxa, 4926 (4), 451 - 500. https: // doi. org / 10.11646 / zootaxa. 4926.4.1"]}

Plecia nessiae Fitzgerald sp. n. (Figs. 18–22) Type Material. Holotype: Male, point-pinned (NHMLA), BRAZIL: “Veadeiros, Go., Brazil, May 1, 1956, F.S. Truxal ” [white label]. “Machris Brazilian Expedition—1956, Los Angeles County Museum” [white label]. LACM ENT 395057 [white data matrix label]. HOLOTYPE, Plecia nessiae Fitzgerald [red label], terminalia dissected. Description. Holotype Male. General coloration. Entirely black to very dark brown, legs dark brown. Head. Three ocelli. Antenna missing. Compound eye holoptic with minute sparse ommatrichia, divided into upper and lower section of larger and smaller facets by slight depression. Face produced anteriorly, duck-bill-like. Clypeus + proboscis long, longer than the length of the head (can be seen folded under the head in Fig. 18). Thorax. Mesonotum polished, shining, with a subtle median and a pair of more distinctive dorsocentral grooves. Anterior portion of grooves with thin dark brownish pruinosity forming longitudinal stripes, mesonotum more thickly pruinose laterally and anteriorly. Mesonotum largely bare with short dark sparse setae in median and dorsocentral grooves as well as laterally. Thoracic pleurae matte, very dark brown, katepisternum with patch of dorsal setae. Legs. Missing fore legs and left hind leg. Remaining legs with dense short dark setae. Hind tibia slender, spindle-shaped. Hind basitarsus slender, sausage-shaped, approximately 4.5 times as long as wide. Wings. 6.5 mm, slightly light brown fumose, darker anteriorly. All veins brown, anterior veins bolder, pterostigma concolorous with wing membrane. R 2+3 short, curved, strongly divergent from R 4+5, ending in C. Venation typical for the genus. Abdomen. With short dark hair. Terminalia (Figs. 19–22). Epandrium (tergite nine) short, almost twice as broad as long with narrow, slit-like posteromedial cleft extending about 1/3 length of sclerite though sclerite creased along entire length. Epandrial lobes apically rather truncate, but with four broad, dark, triangular, posteroventrally-directed, shark-tooth-like lobes on the inner posterior edge. Gonocoxites distinctly convex, bulbous, ventrally broader than long, lacking posteromedian cleft, median projection, and lateral lobes. Gonostylus with two main lobes; a broad, flat dorsal lobe and a more ventral, slender posteriorly-projecting lobe. In posterior view (Fig. 21), gonostylus broad, roughly diamond-shaped with broad truncate dorsal edge and dorsomedial edge black and covered in minute rasp-like teeth and ventral lobe foreshortened and difficult to see. In ventral view (Fig. 20), ventral lobe of gonostylus slender, apically hooked, resembling neck and head of the Lochness Monster (as in the famous, albeit hoaxed, “surgeon’s photograph” of 1934). Female. Unknown. Diagnosis & Remarks. This species is most similar to P. xyele Fitzgerald, which previously had no clear affinity to other species (Fitzgerald 1998); both species share the dark shining scutum, elongated mouthparts, and bilobate gonostylus with rasp-like dorsal lobe. However, P. nessiae can be distinguished by the shape of the epandrium (with four triangular teeth in P. nessiae verses two strong apically rounded lobes in P. xyele) and the very different shape of the gonostylus; in ventral view, the ventral lobe of P. nessiae is slender with the apex hooked resembling the neck and head of the Lochness Monster (Figs. 19 & 23) whereas that of P. xyele is rectangular, apically truncate, but with corners produced into acute points (see Fitzgerald 1998, Figs. 89–91). P. nessiae belongs to the xylele -species-group (see Discussion) and will key to couplet 5 in Hardy’s 1945 key. Etymology. The specific epithet is derived from the name Nessie (a nickname for Scotland’s Lochness Monster) as the gonostylus in ventral view bears a striking resemblance to the neck and head of the Lochness Monster (as e.g., seen in the “Surgeon’s photograph” of 1934 (see Fig. 23 and Tikkanen 2020). Additionally, the epandrium has a row of monstrous teeth along the posterior edge. Distribution. Known only from the holotype collected in Goiás, Brazil., Published as part of Fitzgerald, Scott J., 2021, New species of Neotropical Plecia Wiedemann (Diptera: Bibionidae) and delineation of the americana-, nigra-, and xyele- species-groups, pp. 21-40 in Zootaxa 5005 (1) on pages 31-33, DOI: 10.11646/zootaxa.5005.1.2, http://zenodo.org/record/5141077, {"references":["Fitzgerald, S. J. (1998) Eighteen new species of Neotropical Plecia (Diptera: Bibionidae) and taxonomic notes on the genus. Transactions of the Entomological Society of America, 124 (2), 133 - 164.","Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547.","Tikkanen, A. (2020) Loch Ness monster. Encyclopedia Britannica. Available from: https: // www. britannica. com / topic / Loch- Ness-monster-legendary-creature (accessed 17 July 2021)"]}

Tipula punctifrons Rondani, 1875 ORIGINAL DESCRIPTION: 1875c: 463. TYPE LOCALITY: “ Insula Bonae Fortunae (Borneo), Provincia Sarawak [Bona Fortuna Island, Sarawak Province, Borneo]” (Rondani 1875c: 421). TYPE MATERIAL: 1 ♀, holotype (head, thorax and three legs on one pin, one leg and part of a wing glued to a cardboard stage on a separate pin) (MSNG): Sarawak / Typus / punctifrons Rond. / Tipula punctifrons n° 80 [head, thorax and three legs], Typus / punctifrons Rond. / Tipula punctifrons n. [one leg, part of a wing]. CURRENT STATUS: valid species (Alexander & Alexander 1973: 29); valid species, as Holorusia punctifrons (Oosterbroek, 2020). REMARKS: Rondani (1875c: 463) described Tipula punctifrons from just the female sex, without specifying the exact number of specimens, but giving a single measurement of length, from material collected by G. Doria and O. Beccari. Guiglia (1957: 196) and Raineri & Rey (1996: 59) reported the holotype (♀) in the MSNG., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 384, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Rondani, C. (1875 c) Muscaria exotica Musei Civici Januensis observata et distincta. Fragmentum III. Species in Insula Bonae Fortunae (Borneo), Provincia Sarawak, annis 1865 - 68, lectae a March. J. Doria et Doct. O. Beccari. Annali del Museo Civico di Storia Naturale di Genova, 7, 421 - 464.","Alexander, C. P. & Alexander, M. M. (1973) Family Tipulidae. In: Delfinado, M. D. & Hardy, D. E. (Eds.), A catalog of the Diptera of the Oriental Region. Volume I. Suborder Nematocera. University of Hawaii Press, Honolulu, pp. 10 - 224.","Oosterbroek, P. (2020) Catalogue of the craneflies of the world (Insecta, Diptera, Nematocera, Tipuloidea). Available from: http: // ccw. naturalis. nl (accessed 8 September 2020)","Guiglia, D. (1957) I tipi di ditteri di Camillo Rondani e di altri autori appartenenti alle collezioni del Museo Civico di Storia Naturale di Genova. Annali del Museo Civico di Storia Naturale di Genov a, 69, 193 - 207.","Raineri, V. & Rey, A. (1996). Elenco di tipi di ditteri conservati nel Museo Civico di Storia Naturale \" G. Doria \" di Genova. Annali del Museo Civico di Storia Naturale \" Giacomo Doria \", 91, 27 - 64."]}

Tipula marmoripennis Rondani, 1850 ORIGINAL DESCRIPTION: 1850c: 194. TYPE LOCALITY: “ Venezuela ”. TYPE MATERIAL: not found in this study. CURRENT STATUS: valid species, as Tipula (Eumicrotipula) marmoripennis (Alexander & Alexander 1970: 27, Oosterbroek 2020). REMARKS: Rondani (1850c: 194) described Tipula marmoripennis from just the female sex, without specifying the exact number of specimens, but giving a single measurement of length, from material received from E. Truqui. We were unable to locate any type material of this nominal species in our study., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 384, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Alexander, C. P. & Alexander, M. M. (1970) Family Tipulidae. In: Papavero, N. (Ed.), A catalogue of the Diptera of the Americas south of the United States. Museu de Zoologia, Universidade de Sao Paulo, Sao Paulo, 4, 1 - 259.","Oosterbroek, P. (2020) Catalogue of the craneflies of the world (Insecta, Diptera, Nematocera, Tipuloidea). Available from: http: // ccw. naturalis. nl (accessed 8 September 2020)","Rondani, C. (1850 c) Osservazioni sopra alquante specie di esapodi ditteri del Museo Torinese. Nuovi Annali delle Scienze Naturali e Rendiconto delle Sessioni della Societa Agraria e dell'Accademia delle Scienze dell'Istituto di Bologna, Series 3, 2, 165 - 197, 1 pl."]}

Plecia similis Rondani, 1850 ORIGINAL DESCRIPTION: 1850c: 193. TYPE LOCALITY: “ Insulae S. Sebastiani [San Sebastian Island (Brazil)]”. TYPE MATERIAL: 1 ♂, syntype (MRSN: Box 1755): Plecia Hoff. similis ? Rndn., ♂, Insul. S. Sebasti. G. / Plecia similis Rond. 1850: 193, Ins. S. Seb. [not original label]; 1 ♀, syntype (covered with mold) (MZUN: Box Coll. entomol. extra-europea, Fam. Tipulidae - Gen. Sciara a Culex): Plecia similis Rnd., Ins. S. Sebast. / M. Zool. N° 10889. CURRENT STATUS: valid species (Hardy 1966a: 5). REMARKS: Rondani (1850c: 193) described both sexes of Plecia similis from an unspecified number of specimens received from E. Truqui. Costa (1866: 39) listed a single MZUN specimen numbered “934”. Two syntypes were found in this study., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on pages 63-64, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Hardy, D. E. (1966 a) Family Bibionidae. In: Papavero, N. (Ed.), A catalogue of the Diptera of the Americas south of the United States. Departamento de Zoologia, Secretaria de Agricultura, Sao Paulo, 18, 1 - 20.","Rondani, C. (1850 c) Osservazioni sopra alquante specie di esapodi ditteri del Museo Torinese. Nuovi Annali delle Scienze Naturali e Rendiconto delle Sessioni della Societa Agraria e dell'Accademia delle Scienze dell'Istituto di Bologna, Series 3, 2, 165 - 197, 1 pl.","Costa, A. (1866) Acquisti fatti durante l'anno 1863. Annuario del Museo Zoologico della Regia Universita di Napoli, 3, 13 - 48."]}

Plecia tergorata Rondani, 1875 ORIGINAL DESCRIPTION: 1875c: 462. TYPE LOCALITY: “ Insula Bonae Fortunae (Borneo), Provincia Sarawak [Bona Fortuna Island, Sarawak Province, Borneo]” (Rondani 1875c: 421). TYPE MATERIAL: 1 ♂, holotype (MSNG): Borneo, Sarawak, 1865/1866, Coll. Doria / Typus / tergorata Rond. / Plecia tergorata n° 78. CURRENT STATUS: valid species (Hardy 1973: 442). REMARKS: Rondani (1875c: 462) described Plecia tergorata, without specifying either the number or the sex of the specimens and not giving a range of lengths, from material collected by G. Doria and O. Beccari. Guiglia (1957: 196) and Raineri & Rey (1996: 31) reported the holotype (♂) in the MSNG., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 64, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Rondani, C. (1875 c) Muscaria exotica Musei Civici Januensis observata et distincta. Fragmentum III. Species in Insula Bonae Fortunae (Borneo), Provincia Sarawak, annis 1865 - 68, lectae a March. J. Doria et Doct. O. Beccari. Annali del Museo Civico di Storia Naturale di Genova, 7, 421 - 464.","Hardy, D. E. (1973) Family Bibionidae. In: Delfinado, M. D. & Hardy, D. E. (Eds.), A catalog of the Diptera of the Oriental Region. Volume I. Suborder Nematocera. University of Hawaii Press, Honolulu, pp. 434 - 442.","Guiglia, D. (1957) I tipi di ditteri di Camillo Rondani e di altri autori appartenenti alle collezioni del Museo Civico di Storia Naturale di Genova. Annali del Museo Civico di Storia Naturale di Genov a, 69, 193 - 207.","Raineri, V. & Rey, A. (1996). Elenco di tipi di ditteri conservati nel Museo Civico di Storia Naturale \" G. Doria \" di Genova. Annali del Museo Civico di Storia Naturale \" Giacomo Doria \", 91, 27 - 64."]}

Dilophus similis Rondani, 1868 ORIGINAL DESCRIPTION: 1868b: 40. TYPE LOCALITY: “ Buenos Aires [Buenos Aires (Argentina)]”. TYPE MATERIAL: 1 ♀, syntype, 1 specimen, syntype (sex not determinable, abdomen mostly covered with mold, missing left hind-leg) (MZUF: Box 71): Dilophus similis Rnd., Amer. M. [= South America] / [no identification number]. CURRENT STATUS: valid species (Hardy 1966a: 11). REMARKS: Rondani (1868b: 40) described Dilophus similis, without specifying the number, the sex or the length of the specimens, from material received from P. Strobel. We found two syntypes in this study. Rondani (1868b) indicated the type locality as Buenos Aires (Argentina) where Strobel taught from 1865–1867, but the specimens are labeled “ Am. Mer.” (= “ America Meridionali ”) [South America]., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 63, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Hardy, D. E. (1966 a) Family Bibionidae. In: Papavero, N. (Ed.), A catalogue of the Diptera of the Americas south of the United States. Departamento de Zoologia, Secretaria de Agricultura, Sao Paulo, 18, 1 - 20.","Rondani, C. (1868 b) Diptera aliqua in America meridionali lecta a Prof. P. Strobel annis 1866 - 67 distincta et annotata, novis aliquibus descriptis. Annuario della Societa dei Naturalisti in Modena, 3, 24 - 40, 1 pl."]}

Bibio intermedius Rondani, 1850 ORIGINAL DESCRIPTION: 1850c: 193. TYPE LOCALITY: “ Venezuela ”. TYPE MATERIAL: 1 ♀, lectotype (missing hind-legs and left wing) (MRSN: Box 1755): Bibio intermedius Rndn. / Venezuela [next word illegible] / lectotype Bibio intermedius Rondani, designated by S. Fitzgerald 1997. PARALECTOTYPE NOT EXAMINED: 1 ♀ (missing left wing) (MRSN: Box 1755): Bibio ♀? intermedius Rndn., Venezuela, Genè / Bibio intermedius Rond. 1850: 183, Venezuela. CURRENT STATUS: valid species (Hardy 1966a: 6, Fitzgerald 1997: 249). REMARKS: Rondani (1850c: 193) described Bibio intermedius from just the female sex, without specifying the number of specimens, but giving a single measurement of length, from material received from E. Truqui. Fitzgerald (1997: 249) designated a lectotype (♀) but did not mention an additional female in the MRSN (this additional specimen is a paralectotype)., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on pages 62-63, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Fitzgerald, S. J. (1997) A Revision of Bibio (Diptera: Bibionidae) of Mexico and Central America. Transactions of the American Entomological Society, 123 (4), 225 - 287.","Hardy, D. E. (1966 a) Family Bibionidae. In: Papavero, N. (Ed.), A catalogue of the Diptera of the Americas south of the United States. Departamento de Zoologia, Secretaria de Agricultura, Sao Paulo, 18, 1 - 20.","Rondani, C. (1850 c) Osservazioni sopra alquante specie di esapodi ditteri del Museo Torinese. Nuovi Annali delle Scienze Naturali e Rendiconto delle Sessioni della Societa Agraria e dell'Accademia delle Scienze dell'Istituto di Bologna, Series 3, 2, 165 - 197, 1 pl."]}

Microstylium vestitum Rondani, 1875 ORIGINAL DESCRIPTION: 1875c: 447. TYPE LOCALITY: “ Insula Bonae Fortunae (Borneo), Provincia Sarawak [Bona Fortuna Island, Sarawak Province, Borneo]” (Rondani 1875c: 421). TYPE MATERIAL: 1 ♂, holotype (MSNG): Borneo, Sarawak, 1865/1866, Coll. Doria / Typus / vestitum Rond. / Microstylium vestitum n° 46. CURRENT STATUS: valid species (Oldroyd 1975: 122). REMARKS: Rondani (1875c: 447) described Microstylium vestitum from just the male sex, without specifying the exact number of specimens and not giving a range of lengths, from material collected by G. Doria and O. Beccari. Guiglia (1957: 193) and Raineri & Rey (1996: 30) reported the holotype (♂) in the MSNG., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 59, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Rondani, C. (1875 c) Muscaria exotica Musei Civici Januensis observata et distincta. Fragmentum III. Species in Insula Bonae Fortunae (Borneo), Provincia Sarawak, annis 1865 - 68, lectae a March. J. Doria et Doct. O. Beccari. Annali del Museo Civico di Storia Naturale di Genova, 7, 421 - 464.","Oldroyd, H. (1975) Family Asilidae. In: Delfinado, M. D. & Hardy, D. E. (Eds.), A catalog of the Diptera of the Oriental Region. Volume II. Suborder Brachycera through Division Aschiza, Suborder Cyclorrhapha. University of Hawaii Press, Honolulu, pp. 99 - 156.","Guiglia, D. (1957) I tipi di ditteri di Camillo Rondani e di altri autori appartenenti alle collezioni del Museo Civico di Storia Naturale di Genova. Annali del Museo Civico di Storia Naturale di Genov a, 69, 193 - 207.","Raineri, V. & Rey, A. (1996). Elenco di tipi di ditteri conservati nel Museo Civico di Storia Naturale \" G. Doria \" di Genova. Annali del Museo Civico di Storia Naturale \" Giacomo Doria \", 91, 27 - 64."]}

Bibio subaequalis Rondani, 1868 ORIGINAL DESCRIPTION: 1868b: 39. TYPE LOCALITY: “ Buenos Aires [Buenos Aires (Argentina)]”. TYPE MATERIAL: 1 ♀, lectotype (MZUF: Box 71): Dilophus subaequalis Rnd., Am. Mer. [= South America] / lectotype Bibio subaequalis Rondani, designated by S. Fitzgerald, 1997 / [no identification number]. CURRENT STATUS: valid species (Hardy 1966a: 6, Fitzgerald 1997: 273). REMARKS: Rondani (1868b: 39) described Bibio subaequalis from just the female sex, without specifying either the exact number or the length of the specimens, from material received from P. Strobel. Rondani (1868b) indicated the type locality as Buenos Aires (Argentina) where Strobel taught from 1865–1867, but the specimen itself is labeled “ Am. Mer. ” (= “ America Meridionali ”) [South America]. Fitzgerald (1997: 273) designated a lectotype (♀)., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 63, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Fitzgerald, S. J. (1997) A Revision of Bibio (Diptera: Bibionidae) of Mexico and Central America. Transactions of the American Entomological Society, 123 (4), 225 - 287.","Hardy, D. E. (1966 a) Family Bibionidae. In: Papavero, N. (Ed.), A catalogue of the Diptera of the Americas south of the United States. Departamento de Zoologia, Secretaria de Agricultura, Sao Paulo, 18, 1 - 20.","Rondani, C. (1868 b) Diptera aliqua in America meridionali lecta a Prof. P. Strobel annis 1866 - 67 distincta et annotata, novis aliquibus descriptis. Annuario della Societa dei Naturalisti in Modena, 3, 24 - 40, 1 pl."]}

Bibio longirostris Rondani, 1863 ORIGINAL DESCRIPTION:1863: 89. TYPE LOCALITY: “ Cap. B. Spei [Cape of Good Hope (South Africa)]”. TYPE MATERIAL: 1 ♀, syntype (covered with mold) (MZUN: Box Coll. entomol. extra-europea, Fam. Tipulidae - Gen. Sciara a Culex): Bibio longirostris Rnd., C. B. Sp. / M. Zool. N° 10891. CURRENT STATUS: valid species (Hardy 1980: 215). REMARKS: Rondani (1863: 89) described Bibio longirostris from just the female sex, without specifying the number of specimens, but giving a single measurement of length, from material received from M. Spinola. Costa (1866: 39) listed a single MZUN specimen numbered “936”. We also found one syntype in this study., Published as part of Sforzi, Alessandra & Sommaggio, Daniele, 2021, Catalog of the Diptera types described by Camillo Rondani, pp. 1-438 in Zootaxa 4989 (1) on page 63, DOI: 10.11646/zootaxa.4989.1.1, http://zenodo.org/record/4980621, {"references":["Rondani, C. (1863) Diptera exotica revisa et annotata novis nonnullis descriptis. Eredi Soliani, Modena, 99 pp., 1 pl. [This is the separate that came out before the journal version with a different title, here as Rondani (1864 a)].","Hardy, D. E. (1980) Family Bibionidae. In: Crosskey, R. W. (Ed.), Catalogue of the Diptera of the Afrotropical Region. British Museum (Natural History), London, pp. 213 - 215.","Costa, A. (1866) Acquisti fatti durante l'anno 1863. Annuario del Museo Zoologico della Regia Universita di Napoli, 3, 13 - 48."]}

Pollination studies of South African Asclepiadeae (Apocynaceae: Asclepiadoideae) have mostly examined species in the moist summer-rainfall grasslands, with limited studies of the early-diverging groups occurring in the drier winter-rainfall habitats. This study examined the pollination and floral traits of Eustegia minuta, an unusual species endemic to the winter-rainfall Greater Cape Floristic Region and representing an early-diverging clade within the Asclepiadeae. Observations of floral visitors in Jonkershoek Nature Reserve showed that this species is visited primarily by a species of March fly, Bibio turneri (Bibionidae). These flies moved actively between plants and carried pollinaria on their mouthparts. In addition, an ant species, Camponotus vestitus (Formicidae), and a single honey bee Apis mellifera capensis (Apidae) individual carried pollinaria and may contribute to pollination. Bagging experiments confirmed that flowers require pollinators for reproduction. Flowers produced small amounts (1.2 µl per flower) of concentrated (32.5% sugar) nectar. Pollination success was low (14.5% of flowers were pollinated and 3.4% of flowers developed fruits). Pollen transfer efficiency (PTE) was 5.2%. The corolla reflectance was similar to that of green leaves, but the gynostegium exhibited a relatively bright human-white spectral curve. Floral scent comprised over 50 compounds, but was dominated by various aromatics along with 2,3-heptandione, (E)-4,8-dimethylnona-1,3,7-triene and several unidentified compounds. We conclude that E. minuta is pollinated primarily by the March fly B. turneri, although ants and possibly honey bees may make a lesser contribution. Pollination by bibionid flies has not previously been reported in asclepiads and is extremely uncommon amongst angiosperms.

Simple Summary The mid-Cretaceous amber of Myanmar (also known as Burmese amber) is almost 100 MYA old and represents an invaluable source of information about the evolution of life in the late Mesozoic. This is particularly true for the early flies (lower Diptera) which underwent rapid radiation during the Cretaceous period. Here we describe a remarkable nematocerous fossil fly which shows a character typical of the flies of the suborder Brachycera—with strongly modified antenna—representing new evidence that such a Brachycera-like modification of the antennae has evolved several times during the evolutionary history of Diptera. Abstract A new fossil genus of Bibionidae (Diptera: Bibionomorpha), Burmahesperinus gen. nov., from the mid-Cretaceous Burmese amber, is described and illustrated (type species Burmahesperinus antennatus sp. nov., the other two species included are B. conicus sp. nov. and B. pedicellatus sp. nov.). The new genus is tentatively placed in a new subfamily, Burmahesperininae subfam. nov. of the family Bibionidae. Its possible phylogenetic position is briefly discussed. The new genus, as well as the subfamily, possesses the wing venation similar to the recent genus Hesperinus Walker, 1848, in combination with Brachycera-like modification of both the male and female antenna and the overall habitus typical of fungus gnats (Sciaroidea).

Key to the species of New World Penthetria Based on males (eyes holoptic). Females (eyes dichoptic) of some of these species are presently unknown (P. dolichopeza) or indistinguishable. To improve the efficiency of the identification process of specimens from USA and Canada proceed directly to couplet six (though females from USA / Canada are presently indistinguishable, they may be separated with relative confidence based on geographic distribution in areas where species appear to be allopatric (see distribution of species in Maps 2 & 3)). 1 Ventromedian lobes of posterior margin of gonocoxites strongly developed (Fig. 34, 45, vml) with ventromedian cleft often slightly deeper or more narrow in appearance due to stronger flanking lobes (Fig. 34 inset); gonostylus relatively slender in posterior view (Fig. 35) and apically acute; posterior margin of tergite nine with relatively shallow cleft, usually about one-third depth of tergite; tergite nine never deeply emarginate (over one-half length of tergite), shelf-like posteriorly (Fig. 10), or with a field of densely-set, short, black, spine-like setae on posteroventral edge of tergite (Fig. 5, sls); female with tergite nine well developed and strongly lobate posterolaterally (Fig. 54), cerci with second (ultimate) segment relatively short, and posteromedian lobes of sternite eight relatively broad (Fig. 55); South America..................... P. neonigrita Fitzgerald n. sp. - Ventromedian lobes of posterior margin of gonocoxites weakly (Fig. 11, vml) to moderately (Figs. 20 & 25, vml) developed, sometimes entirely absent (Fig. 15); posteromedian cleft usually shallower and broader (Fig. 20, vmc) or entirely absent; gonostylus variable, but not slender in posterior view unless tergite nine deeply emarginate or gonostylus apically notched; tergite nine variable; female terminalia not with the above combination of characters; Canada to Central America.............. 2 2 Gonostylus glossy, shining, with long hairs basally, but only minute sparse hairs beyond base (Figs. 4–6, 9–11); tergite nine with posteromedian emargination deep, extending at least half, but usually more, the length of the tergite (Figs. 4–5, 9) and posteroventral edge bearing a field of densely-set, short, black, spine-like setae sharply contrasting typical setae on remainder of tergite (Fig. 5, sls; can be difficult to see in undissected specimens); tergite nine sometimes shelf-like posteroventrally (Fig. 10); apex of gonostylus broadly rounded (Figs. 9–11) or coming to a narrow rounded point (Fig. 5), never apically truncate or notched (Figs 16–20); females with second (ultimate) segment of cerci elongate and posteromedian lobes of sternite eight relatively narrow (Figs. 46–48); in both sexes vein R2+3 sometimes with a basal appendix (Fig. 2, ba); Mexico and Central America............................................................................................ 3 - Gonostylus with long hairs basally as well as beyond base (e.g., Figs. 7–8); tergite nine without posteromedian emargination or with emargination more shallow and most often extending one-fifth to one-third the length of the tergite, but sometimes slightly over one-half the length of the tergite; vein R 2+3 without a basal appendix (e.g., Figs. 21, 23); tergite nine never shelf-like or with posteroventral edge with a field of densely-set, short, black, spine-like setae sharply contrasting typical setae on remainder of tergite; gonostylus variable; females with second (ultimate) segment of cerci shorter and posteromedian lobes of sternite eight broader (Figs. 49–53, 56) (females of these species indistinguishable except some by geographic range); widespread...... 4 3 Ninth tergum almost completely divided into two plates by posterior emargination (Fig. 9); posterior, inner (ventral) surface of ninth tergite developed into a pair of broad flat shelves when viewed posteriorly (Fig. 10); gonostylus broad and broadly rounded apically (Figs. 9–11); R 2+3 usually without, but sometimes with a basal appendix; female with sternite ten truncate/broadly rounded posteriorly? (as in Fig. 49; sternite 10 not visible in Fig. 48 as it is partly telescoped within preceding segments) (but see notes on this character in “Remarks” under P. appendicula).................................. P. distincta Hardy - Ninth tergum not so deeply cleft (Fig. 4); posterior, inner (ventral) surface of ninth tergite not developed (or at most only very weakly developed) into a pair of broad flat shelves when viewed posteriorly (Fig. 5); gonostylus not as broad (Fig. 5); R 2+3 usually, but not always, with a basal appendix (Fig. 2); female (Fig. 3) with sternite ten tapered posteriorly to a rounded point? (Fig. 47) (but see notes on this character in “Remarks”)..................................... P. appendicula Hardy 4 Hind basitarsus, parallel-sided, very slender elongate (hind tibia only about 2.5 times as long as basitarsus; Fig. 12, hb); gonostylus short and stout with a distinct anteroapical thorn (Figs. 14–15); gonocoxite dorsally with an apical, medially-directed lobe just anterior to the gonostylar socket (Fig. 14, dal); ventromedian lobes of gonocoxites absent (Fig. 15); southern Mexico, Costa Rica................................................................. P. dolichopeza Fitzgerald n. sp. - Hind basitarsus usually robust to slightly swollen and sausage-shaped, sometimes more slender, but never slender and greatly elongated (Figs. 23, 30–31, hb); gonostylus not as above; gonocoxite dorsally without an apical medially-directed lobe just anterior to the gonostylar socket; ventromedian lobes of gonocoxites variable; widespread........................... 5 5 In dorsal and ventral views, divergent horn-like lobes of paramere more strongly projecting caudally and ventrally, often appearing apical (even though really more subapical in position) (Figs. 24–26, dlp), sometimes divergent lobes slightly less projecting (Figs. 28–29) making them barely visible or barely not visible in a strictly dorsal view, but in the latter case at least apex (most posterior aspect) of paramere slightly laterally compressed into a ridge so that apex appears more narrow (as an apical nubbin) in dorsal view rather than broadly rounded (Fig. 29); apex of gonostylus (Figs. 24–26, 28–29) usually broadly rounded or broadly rounded and culminating in an obtuse point medially, sometimes apically slightly truncate, but never with an apical notch; tergite nine uncleft or relatively shallowly cleft (up to about one-third its length) (Fig. 24); Mexico and Central America............................................................................ P. mexicana (Hardy) - Divergent horn-like lobes of paramere not visible in dorsal view. In ventral view, divergent horn-like lobes less developed, not strongly projecting or appearing apical, but more collar-like and more confluent with posteroventral edge of paramere (Figs. 8 & 20, dlp); apex (most posterior aspect) of paramere rounded, dome-like in dorsal view, not laterally compressed into a narrow ridge/nubbin, and often with a minute notch (Figs. 7 & as in 16 & 20, p); gonostylus variable; Canada to Central America.. 6 6 Apex of gonostylus minutely truncate or with a small notch (the anterodorsal side of the notch often developed into a small point) (Figs. 16–20, 36–39); Canada, northwestern USA and USA east of the Rocky Mountains....................... 7 - Gonostylus apically broadly rounded or broadly rounded and culminating in an obtuse median point (Figs. 7–8) or, in some Mexican and Central American specimens gonostylus very slightly truncate apically (as in Fig. 19); Southern Arizona, USA south to Central America....................................................... P. arizonensis Fitzgerald n. sp. 7 In posterior view, gonostylus more robust (Fig. 40); in dorsal view, paramere more broadly rounded, less diamond-shaped (Fig. 38, p); USA & Canada east of the Rocky Mountains.......................................... P. heteroptera (Say) - In posterior view, gonostylus more slender (Fig. 41); in dorsal view, paramere more diamond-shaped (Fig. 39, p); northwestern USA, widespread in Canada........................................................ P. yakima Fitzgerald n. sp.

Penthetria neonigrita Fitzgerald n. sp. (Figs. 30, 33–35, 45, 54–55, Map 5) Type Material. Holotype: Male (Fig. 30), point-pinned (NHMLA), COLOMBIA, Nariño Laguna LaCocha, IX– 26–71, GE Bohart [white label] / LACM ENT 395043 [white label with data matrix barcode] / HOLOTYPE, Penthetria neonigrita Fitzgerald [red label]. Missing left foreleg. Paratypes: Same data as HT, 3M, 3F (NHMLA), 1M (SFC). Additional Material examined. ARGENTINA: TUCUMAN: 4 km S Capitan Cáceres, MT in old vegetated river channel, 25.x–12.xi. 2003, 430 m, 27°13.54’S, 65°38.34’W, M.E. Irwin, F.D. Parker, 1F (SFC); BOLIVIA: COCHABAMBA: S. Corani, Yungus El Chapare, 29–31.I.1976, 2900 m, L.E. Pena, 1F (CNCI); Paracti, Chapare, 1–4.II.1976, 2200 m, L.E. Pena, 3F (CNCI); Incachaca, 25–31 VIII 1956, L.E. Pena, 2M (CNCI); LA PAZ: Prov. Nor Yungas, Cotapata, 16°17.2’S, 67°51.0’W, 1-XII-2011, S.M. Clark, 1M (BYUC); COLOMBIA: Santa Marta National Park, 1950 m, 23.xi.2010, 11.10°N, 74.07°W, J.H. Skevington, 1M (CNCI); CAUCA: Páramo de Puracé, 26 II 1970, ca. 3400 m, D.M. Wood, 1M (CNCI); NARIÑO: Mallama, 1943, F. R. Fosberg, 1M (USNM); ECUADOR : CAÑAR: El Tambo, 2800 m, 4–7.III.65, Pena, 2M (CNCI); CARCHI: Tulcan, 2800 m, 27. VI. 65, L. Pena, 1M (CNCI); Troya, 2950 m, 11–13. VI.1965, L.E. Pena, 6M (CNCI); Cerro Chiles, 3200–3300 m, 26–27. VI. 65, Pena, 7M (CNCI); Cerro Pelado, 25 VI 1965, 3200 m, L. Pena, 20M, 3F (CNCI); COTOPAXI: Salcedo, 2650 m, 22.II.65, L. Pena, 1M (CNCI); NAPO: 6.38 km W Baeza, Hwy E- 20, 1987 m, 25 Jan 2012, B. Kondratieff, 2M (CSUC); PICHINCHA: 0°16’S, 78°16’W, 28.II.76, G. & M. Wood, 1M (CNCI); VENEZUELA: Camp Rangel, 7-26-50, Trop. For., 1260 El, E. Schwarz, 10F (USNM); ARAGUA: Rancho Grande, 18–27.II.71, 1100 m, G. & M. Wood, 1F (CNCI); CARACAS: Sher. Humb. Hotel, 9 XII 1970, J.W. Boyes, 1M, 1F (CNCI), 1M, 1F (SFC); LARA [?]: Yacambo, 1200 m, 10 May 1981, H.K. Townes, 1M (CNCI); MERIDA: 3800 m, 5 km NE Pico el Aguila, IX- 12-1973, R. M. Bohart, 1M (SFC); Merida, Libertador, VII 31979, R. W. Brooks, A.A. Grigarick, J. McLaughlin, R.O. Schuster, 1M (SFC); Merida, XI-17-72, G.E. Bohart, 9M (NHMLA); Merida, 17–21 May 1996, W.C. Pitt, 1F (NHMLA). Description. Male (Fig. 30). Body length: approx. [9.0] mm. Head. Black. Compound eye holoptic, covering virtually all of dorsal and lateral surface of head, with lateral longitudinal step dividing upper and lower portion of eye. Eyes nearly bare, with some very minute, very sparse ommatrichia present. Antennae black, ten flagellomeres with black setae. Flagellomeres wider than long except first flagellomere about as wide as long and ultimate flagellomere much smaller than preceding segments, about as wide as long. Three ocelli on well-developed tubercle. Thorax matte dark brown to blackish with light brown highlights on humeral ridge and posterior portions of pleurae. Thorax largely bare except fine short dark hairs on mesonotum in broad dorsocentral rows and a few hairs anterolaterally. Scutellum with sparse short fine dark hair and middle of katepisternum with long dark hairs. Legs. Slender elongate. Entirely dark brownish-black with dense short dark appressed hairs. Hind femur slightly thickened (clavate) on apical third. Hind tibia slender elongate virtually parallel-sided. Hind basitarsus robust to slightly swollen and sausage-shaped, about four times as long as wide (Fig. 30). Wings (Fig. 30). 8.0–[10.0] mm (n=7), brown fumose, darker costally. Veins brown, pterostigma concolorous with membrane. Venation as Fig. 30. Sc long, complete. R 2+3 elongate, subparallel to R 4+5, usually without basal appendix (HT with slight indication of an appendix on one wing and one female paratype with a basal appendix). CuA and CuP apically convergent, but reaching wing edge independently (not meeting). Abdomen. Dark brown to black. Terminalia (Figs. 33–35, 45) dark brown to black. Tergite nine broader than long, posterior margin with shallow emargination reaching about one-third depth of sclerite. In dorsal view, gonocoxites dorsoapically without small apically rounded medially-projecting lobe just dorsal to gonostylar socket. In ventral view, posterior edge of medially fused gonocoxites + hypandrium with a relatively narrow, deep, median cleft bounded by a pair of strongly developed ventromedian lobes (Fig. 34 & 34 inset, vml). In posterior view, gonostylus relatively slender, gently curved, apically acute (Fig. 35). In dorsal (Figs. 33, 45) and ventral (Fig. 34) views fused parameres projecting from out of genital capsule, shiny brown heavily sclerotized dome-like. Cerci fleshy, apically rounded with setae. Female. Essentially as in male. Body about 9.0 mm and wing 9.0–11.0 mm (n=4). Eyes dichoptic. Antennae with ten flagellomeres. Female hind basitarsus slender elongate. Abdomen stout. Female terminalia (Figs. 54–55): Tergite nine more strongly developed than other New World species, medially subdivided, but posterolaterally broadly lobate. Tergite ten apparently absent. Cerci two-segmented, ultimate segment relatively short. Subgenital plate (= sternite eight) large, longitudinally subdivided, posterior margin with a pair of broad lobes medially. Y-shaped genital fork present. In addition to genital fork, a minute pair of sclerites present between the posterior margin of the subgenital plate and the anterior margin of sternite ten. Sternite 10 posteriorly broadly rounded. Three rounded, sclerotized, capsule-like, spermathecae present. Diagnosis. Males of P. neonigrita can be distinguished from other New World species by the following combination of characters: ventromedian lobes of gonocoxite strongly developed (Fig. 34 and inset & 45, vml; these ventromedian lobes are more developed in P. neonigrita than any of the other New World species), ventromedian cleft appears deeper and narrow due to strongly developed ventromedian lobes (Fig. 34 inset), gonostylus relatively slender in posterior view (Fig. 35), apically acute, posterior emargination of tergite 9 relatively shallow and broad (cleft about one-third depth of tergite) without shelf-like development or field of densely-set, short, black, spinelike setae. In dorsal view, the paramere of P. neonigrita (Fig. 45) is bulbous and dome-like; very similar to that of P. heteroptera. Remarks. This species was treated by Hardy (1945) as Penthetria nigrita Perty; see “species removed from Penthetria ” below. Some specimens studied have the apical half of the gonostylus slightly more expanded in dorsal/ventral view though still distinctly slender in posterior view (compare Figs. 34 & 34 inset; difference in length of gonocoxite in these two figures is due to distortion from slide mounting). Females of P. neonigrita can be distinguished from New World congeners by the strongly developed, posterolaterally lobate tergite nine and sternite eight with relatively broad posteromedial lobes (Figs. 54–55). Etymology. The specific epithet is derived from the Greek neos (new) and nigrita (from P. nigrita Perty) since neonigrita is a new name for those taxa that had previously been treated as P. nigrita Perty sensu Hardy (1945). Geographic & Seasonal Distribution. Venezuela, Colombia, Ecuador, Bolivia, and Argentina (Map 5). Hardy (1945) also lists this species from Brazil and Peru. This species has been collected every month of the year except April (Table 1)., Published as part of Fitzgerald, Scott J., 2021, Penthetria Meigen (Diptera: Bibionidae): Revision of the New World species and world catalog, pp. 451-500 in Zootaxa 4926 (4) on pages 479-482, DOI: 10.11646/zootaxa.4926.4.1, http://zenodo.org/record/4529512, {"references":["Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547."]}

Penthetria distincta Hardy, 1945 (Figs. 9–11, 42, 48, Map 1) Type Material. Holotype male (not examined): GUATEMALA: “Antigua,” 24 June 1923, E.G. Smyth (USNM). Paratypes (examined): GUATEMALA: GUATEMALA: Guatemala City, 2 May 1923, E.G. Smyth, 4M (USNM), 20 July 1923, 1M (USNM); SACATEPÉQUEZ: “ Antiqua,” D.G. Eisen, 2M (USNM); “ Antiqua,” 24 June 1923, E.G. Smyth, 1F (allotype) (USNM); QUETZALTENANGO: Volcan Santa María, Nov., Schaus & Barnes, 1M (USNM). Additional Material examined. EL SALVADOR: LA LIBERTAD: Santa Tecla, 7 14 95, P. A.B., 1M, 1F (USNM); GUATEMALA: GUATEMALA: Puerta Parada, 1850 m, Bosques cipres, J.C. Schuster, 15–22 XII 2012, 1M (UVGC), 22–29 XII 2012, 2M (SFC), 29 XII 2012 – 5 I 2013, 1F (SFC), 22 II–1 III 2014, 1F (SFC); Puerta Parada, 1850 m, Casa Jack, 14.556630, -90.463362, 5–12 Jan 2013, J.C. Schuster, 1F (SFC); Puerta Parada, 1840 m, 7–14 VII 2018, J.C. Schuster, 1F (UVGC), 14–21 VII 2018, 1M (SFC); TOTONICAPÁN: Momostenango, 9 Dec. 1979, 1M (UCDC); MEXICO: CHIAPAS: 7200 ft., S. Crist. las Casas, 1 June 1969, Malaise trap, 5M, 1F (CNCI); Sn. Cristobal, 22.VII.1969, L.A. Kelton, 1M (CNCI). Diagnosis. Males of P. distincta can be distinguished from all New World congeners by the following combination of characters: tergite nine with posteromedial emargination deep (nearly subdividing the tergite) (Fig. 9) with the apices of the resulting lobes truncate and shelf-like (best observed in posterior view) (Fig. 10), posteroventral edge of tergite nine with a field of densely-set, short, black, spine-like setae, which contrast the typical setae on the remainder of the tergite (difficult to see in undissected specimens), gonostylus shining, basally with long hairs, but more distally with only very minute and spare hairs, slender and apically coming to a narrowly rounded point (Figs. 9–11), ventromedial lobes of gonocoxite absent to very weakly developed (Fig. 11), and R 2+3 often with a basal appendix (as in Fig. 2). Remarks. P. distincta is a fairly large species with male wing 7.0–9.5 mm (n=4) and female wing 12.0–12.5 mm (n=2) and is most similar to P. appendicula (see “Remarks” under P. appendicula). Geographic & Seasonal Distribution. Guatemala and Mexico (Map 1); additional Guatemalan records in Hardy (1945). Seasonal distribution summarized in Table 1., Published as part of Fitzgerald, Scott J., 2021, Penthetria Meigen (Diptera: Bibionidae): Revision of the New World species and world catalog, pp. 451-500 in Zootaxa 4926 (4) on pages 467-469, DOI: 10.11646/zootaxa.4926.4.1, http://zenodo.org/record/4529512, {"references":["Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547."]}

Penthetria nigerrima (Bellardi), 1859 Type Material & Remarks. The type (s) of Penthetria nigerrima (originally described in Plecia) could not be located. The original description states of the type (s): “Collezioni del Museo zoologico di Parigi, di Saussure e Bellardi” (Collections of the Zoological Museum of Paris, Saussure and Bellardi). However, no types could be located at the Muséum National d’Histoire Naturelle in Paris (Christophe Daugeron and Emmanuel Delfosse (MNHN), personal communication, 2019) nor at the Muséum d’Histoire Naturelle, Geneva, Switzerland, where the collection of Henri Louis Frederic de Saussure is housed (Emmanuel Toussaint (MHNG), personal communication, 2019). According to a historical account of Saussure’s travels and collecting in Mexico (Papavero 1973), Saussure visited Veracruz, Córdoba, Tospán, Orizaba, Puebla, Mexico City, Tampico, and other cities in the interior and returned to Geneva with the specimens. During Bellardi’s work on the “Saggio di Ditterologia Messicana” he apparently had access to about 100 specimens collected by Saussure (and his traveling companion Adrien Louis Jean Francois Sumichrast) and presumably some of these specimens were retained and became part of the Bellardi Collection (Papavero 1973). Unfortunately, the Bellardi Collection (housed at Museo Regional de Scienze Naturali, Turin, Italy) was inaccessible during the time of this study due to renovations of the museum (Fulvio Giachino (MRSN), personal communication, 2019, no response in 2020) and it is unclear if any specimens of P. nigerrima determined by Bellardi exist there. Hardy (1945) states that the type of P. nigerrima is in Paris and that the type locality is Orizaba, Mexico. However, this is information given by Bellardi in the original description, and it does not appear that Hardy examined the type of P. nigerrima as it is not listed under the material he examined (he states that “the writer has studied topotypic specimens”). Due to the fact that Bellardi’s original description is devoid of any useful information and that Hardy did not examine the type, one can only assume that Hardy’s concept of P. nigerrima is based on the “topotypic specimens” he studied from Orizaba. Unfortunately, there are at least two species of Penthetria that have been collected in Orizaba. The first is presumably the one illustrated by Hardy (1945) under the name P. nigerrima (possibly synonymous with P. arizonensis though the ventromedian lobes in Hardy’s (1945) illustration are more similar to those found in P. neonigrita) and the second, found among material at USNM represents P. mexicana. Two species from the type locality leaves the true identity of P. nigerrima irreconcilable without a study of the missing type. Considering this, P. nigerrima is treated as unrecognized (nomen dubium) until the type can be located and studied. Hardy (1966) listed records of P. nigerrima from Mexico, Ecuador, and Colombia, and the South American records were repeated in later works by Fitzgerald (2000) and Falaschi et al. (2016). However, until the types can be studied and the true identity of P. nigerrema revealed, all previous records of this species should be viewed as potentially being based on misidentification and therefore ignored., Published as part of Fitzgerald, Scott J., 2021, Penthetria Meigen (Diptera: Bibionidae): Revision of the New World species and world catalog, pp. 451-500 in Zootaxa 4926 (4) on page 493, DOI: 10.11646/zootaxa.4926.4.1, http://zenodo.org/record/4529512, {"references":["Papavero, N. (1973) Essays on the History of Neotropical Dipterology, Volume II. Museu de Zoologia, Universidade de S \" o Paulo, S \" o Paulo, 446 pp.","Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547.","Hardy, D. E. (1966) Family Bibionidae. In: Papavero, N. (Ed.), A Catalogue of the Diptera of the Americas South of the United States. Departamento de Zoologia da Secretaria da Agricultura do Estado de S \" o Paulo, S \" o Paulo, pp. 1 - 20.","Fitzgerald, S. J. (2000) Bibionidae. In: Llorente Bousquets, J. E., Gonzalez Soriano, E. & Papavero, N. (Eds.), Biodiversidad, Taxonomia y Biogeograpfia de Artropodos de Mexico. Vol. II. Universidad Nacional Autonoma de Mexico, Mexico, pp. 627 - 634.","Falaschi, R. L., Oliveira, S. S. & Amorim, D. S. (2016) Family Bibionidae. Zootaxa, 4122 (1), 20 - 25. https: // doi. org / 10.11646 / zootaxa. 4122.1.5"]}

Penthetria heteroptera (Say), 1823 (Figs. 1, 16–21, 38, 40, 50–51, 57, Map 3) Penthetria atra Macquart, 1834: 175 (by monotypy). Pennsylvania, USA. [HT male BMNH; examined]. Penthetria longipes (Loew), 1858a: 109 (originally described in Plecia). Louisiana, USA. [type could not be located for study; not at MCZC (online database accessed 2019) or ZMHB (Werner, 1999)]. (McAtee (1921) suggested this species may be conspecific with P. heteroptera and it was treated as such by Hardy (1945) though without discussion of the synonymy). Penthetria lugubris Harris, 1835: 596. Massachusetts, USA. Nomen nudum. Type Material. Male, USA: “ Maryland ” (Say 1823, as Bibio heteropterus). Like many of Thomas Say’s types, the type (s) of this species could not be located and may be lost or destroyed. Evenhuis (1997) notes that due to exchanges with colleagues, some of Say’s types still exist in a handful of collections. However, the type (s) of P. heteroptera were not found at ANSP, BMNH, MZHF, NHMW, or OXUM. Despite the fact that the type of P. heteroptera could not be studied, the identity of this species seems sound as it is the only species of Penthetria currently known to occur in the eastern half of the United States, which includes the type locality in Maryland (material from Maryland has been studied to help establish the concept of P. heteroptera utilized herein (e.g., see Figs. 16, 20–21, 38, and material examined). It is noteworthy though that the most eastern record of P. yakima is Ontario, Canada, and it is possible that this species does exist in the northeastern USA. Material Examined. CANADA: ALBERTA: Waterton Lakes, 29 VIII 1926, N. Criddle, 1M (CNCI); Elkwater Park, 15 VIII 1952, L.A. Konotopetz, 1M (CNCI); Edmonton, 7 IX 1936, F.O. Morrison, 1M (BYUC); BRITISH COLUMBIA: mi 233 Al. Hwy, 29 VIII 1948, W. R. Mason, 1M, 1F (in copula) (CNCI); Alaska Hwy, Lum & Almer, 58°N, Aug 29 1948, Mason & Hughes, 1M (CNCI); MANITOBA: Napinka, 24 VIII 1927, R. M. White, 1M (CNCI); Aweme, 27 VIII 1925, R. D. Bird, 1M (CNCI); The Pas, 14-Sept-51, W. Krivda, 1M (CNCI); Winnipeg, 16- IX-09, J.B. Wallis, 1M (CNCI); NEW BRUNSWICK: Greys Mills, 15 IX 1922, R. P. Gorham, 1M (CNCI); ONTARIO: Ottawa, 27.IX.12, 1M (USNM); St. Lawrence Is. Nat. Park, Mulcaster Island, 5 XI 1976, W. Reid, Code 48294-50, 1M (CNCI); Toronto, 1M (BYUC); Ottawa, 8/IX/11, J.D. Tothill, 1M (CNCI); Elgin Co., Springwater Con. Area, 20 Sept 1992, Coll. # 495, Ian Carmichael, 1M (CNCI); Metcalfe, 29 IX 1984, B.E. Cooper, 1M (CNCI); fen 5 mi. S. Richmond, 19–25 IX 1978, D.M. Wood, 1M (CNCI); Merivale, 22 Sept 1951, R. Lambert, 1M (CNCI); N. Burgess Twp., Lanark Co., 22 IX 1968, D.M. Wood, 1M (CNCI); Lake Muskoka, 7 IX 1925, G.S. Walley, 1M (CNCI); Maynooth, 5 IX 1953, J.F. McAlpine, 1M (CNCI); SASKATCHEWAN: Moose Jaw, Dyar & Caudell, 2M (USNM); 5 km E of Leask, YPT, 31.VIII.05, slough margin (freshwater), J. R. Vockeroth, 1M (SFC); Indian Head, 19 IX 1928, K. Stewart, Rb-38- Cb, 50-III-321, 1M (CNCI); Cecil, 6 IX 1977, F.J.H. Fredeen, 1M (CNCI); Moose Jaw, 5 IX, N. Criddle, 1M (CNCI); vi–viii 2005, J. R. Vockeroth, 2M (CNCI); Estevan, 6 IX, N. Criddle, 1M (CNCI); Swift Current, 17 IX 1940, A. R. Brooks, 1M (CNCI); Hudson Bay, 15 IX 1959, J. R. Vockeroth, 1M (CNCI); Regina, 5-Sept-03, 1M, 1F (in copula) (CNCI); QUEBEC: St. Johns, 23.IX.05, 1M (USNM); Lake Edward Camp, Laurnetide Limits, 15 IX 1948, 1M (CNCI); Abbotsford, 7 IX, 1937, G.E. Shewell, 2M (CNCI); Old Chelsea, 25 IX 1955, J. R. Vockeroth, 1M (CNCI); Mt. Orford, 9 IX 1937, G.E. Shewell, 1M (CNCI); Summit Rigaud Mtn., 24 IX 1985, B.E. Cooper, 1M (CNCI); Gatineau Park nr. Champlain Lkout., 22 IX 1991, J.M. Cumming, ex. in copula, 1M, 1F (CNCI); Laniel, 14 IX 1939, J.L. Hitchon, Exp No. 12128-15, 1M (CNCI); Norway Bay, 30 VIII 1938, G.A. Hobbs, 1M (CNCI); Beech Grove P.Q., 24 IX 1954, C.D. Miller, 2M (CNCI); Masham Twp., Gatineau Co., IX 1977, D.M. Wood, 2M (CNCI); Lanoraie, 20- IX-80, F. Liard, 2M (CNCI); USA: COLORADO: Colorado Springs, Sept, 1M (USNM); Boulder, Sept, S.A. Rohwer, 2M, 1F (1 pr. in copula) (USNM); campus, Univ. of Colorado, Boulder, 1M (USNM); “ Colo.,” 2773, 1M (CSUC); Larimer Co., Lory SP, Arthurs Rock Trail, 09 IX 1997, Burt, J.M., 1M (CSUC); Masonville, 9/5/‘3[?], 1M (CSUC); Masonville, 9 6 ‘34, M. T. James Col., 3M (CSUC); Weld Co., 9-29’35, 1M (CSUC); Larimer Co., 19 Sep 1992, Anderson’s Atlas, Upper Cherokee Park, Bjostad, 3M (CSUC); Larimer Co., 18 Sept 1997, Res. dam, D. Leatherman, E. Hamilton, 2M (CSUC); Larimer Co., Poudre River Rt. 14, Ansel Waltrous, 9 IX 1986, P. Kleintjas, 1M (CSUC); Douglas Co., 28 Sept 1988, Malaise Trap over buried pig, B. Kondratieff, 1M (CSUC); Larimer Co., 30 Sept. 1993, Phantom Canyon, S. Fitzgerald, 1M (CSUC); Sedgwick Co., 17 Sept 1993, jct. US 385 & CR4, ex. ponderosa pine, D. Leatherman, 1M (CSUC); CONNECTICUT: Stamford, 20 Oct 1935, 1M (USNM); Stamford, B. T. R. Lab Col., 15 Oct 1937, 1M (USNM), 27 Oct 1937, 1M (USNM); Redding, A.L. Melander, Nov 30, 1M (USNM), 21 Oct ’28, 2M (USNM), 3 Oct 36, 1M (USNM), 13 Oct 35, 1M (USNM); DISTRICT OF COLUMBIA: Washington D.C., Rock Creek Park, 28 Oct 1956, P.H. Arnaud Jr., 1M (USNM); FLORIDA: Putnam Co., Univ. of FL Res., 26/ 27 Nov 1946, R. G. Bellamy, F.C. No. 2045, 1M (CNCI); GEORGIA: Black Mt., 11-2-46, P.W. Fattig, 1M (USNM); IOWA: Ames, 1959, H.H. Knight, 1M (USNM); KANSAS: Douglas Co., 900 ft., September, A.L. Melander, 1M (USNM); MAINE: Hancock Co., 12 mi E Aurora, 28 IX 1984, D.M. Wood, 1M (CNCI); MARYLAND: near Plummer I, 11. Oct. 21, H.S. Barber, 1M (USNM); Patuxent Ref Bowie, 9-X-1944, Mitchell, 1M (USNM); Hagerstown, 27-Sept-12, 1M (USNM); nr. Plummers Id, 10.19.14, R. C. Shannon, 1M (USNM); Plummers I, 5.X.12, J. R. Malloch, 3M (USNM); Plummers Id, R. C. Shannon, 28.X.15, 1M (USNM), 10.X.14, 1M (USNM); Bladensburg, 23.IX.15, R. C. Shannon, 5M (USNM); Plummer’s Island, H.S. Barber, 30.10.07, 1M (USNM), 8.X.1902, 1M (USNM); Largo, 10/16/58, 1M (OSAC); MASSACHUSETTS: Southbridge, S.W. Bromley, Sept 19, 1M, 1F (USNM); Amherst, 9 Oct 1923, 1M (USNM); Middlesex Co., Lincoln, Malaise trap, E. T. Armstrong, 12–13 Oct 1982, 1M (USNM), 14 Oct 1982, 1F (USNM), 15 Oct 1982, 1M (USNM); Hampshire Co., W. Chesterfield, 27 Sept. 1971, A.B. Gurney, 1M (USNM); Beverly, 4-Oct-68, 2M (USNM); Beverly, Burgess, 12.10.75, 1M (USNM), 8.10.75, 1M (USNM); Cape Cod, Eastham, 20 IX 1992, J. R. Vockeroth, in Acer rubrum swamp, 1M (CNCI); Mount Wachusett, Princeton, 13 Sept 1922, W. T. M. Forbes Coll., 1M (BYUC); MICHIGAN: Livingston Co., E.S. George reserve, 7 Oct 1949, 185, K. Bohnsack, 2M (USNM); E. Lansing, 5.X.1939, C. Sabrosky, 1M (USNM); Luce Co., 8-30-52, R. R. Dreisbach, 1M (USNM); Delta Co., 8-25-52, R. R. Dreisbach, 2M (USNM); Ag. Coll. Mich., 635, J.M. Aldrich, 1M (USNM); Ag. Coll. Mich, 635, C.F. B., 2M (CSUC); Ag. Coll. Mich, 421, C.F. B., 1M (CSUC); MINNESOTA: St. Anthony Park, Lugger, 1M (USNM); MISSISSIPPI: Lafayette Co., V–VI 1962, F.M. Hull, 1M (CNCI); MISSOURI: Douglas Co., 2 Oct 2004, Hunter Cr., CRFF-210, SE Ava, B. Kondratieff, R. Zuellig, 1M (CSUC); MONTANA: “ Mon.,” 1M (USNM); NEBRASKA: Dunbar, W.W. Wirth, 13.IX.50, 1M, 7F (USNM); NEW JERSEY: Sussex Co., Coleville, 11 Oct 1970, J.W. Adams, 3M (USNM); Dyckman St, 3-Oct-26, A.L. Melander, 1M (USNM); Midland Park, hovering in apple orchard, E.A. Cohen Jr., Oct 1995, 1M (USNM); NEW YORK: Ithaca, 1M (USNM); Greene Co., 2500 ft., L.O. Howard, 1M (USNM); Hartsdale, G.P. Engelhardt, 9.X.1901, 1M (USNM), 8.X.1936, 1M (USNM); Hamilton Co., 13 July 2009, Thayer Lake outlet, Shingle Shanty Research Stn, 43.95N, 74.75W, BLT, L. Myers, 1M (CSUC); Essex Co., 15 Sept 2007, Small Stream, Rt 73 Nr. Round Pond, L. Myers, 1M (CSUC); PENNSYLVANIA: Lehigh Gap, 5-X-03, 1M, 1F (in copula) (USNM); Wilmerding, A.L. Melander, IX.13, 1M (USNM), IX.15, 1M, 1F (USNM), IX.23, 2M (USNM); SOUTH DAKOTA: “S.D.,” J.M. Aldrich coll., 12M, 1F (USNM); Brookings, 3M (USNM); TENNESSEE: Greene Co., 19 Oct 1985, Kondratieff, 2M (CSUC); TEXAS: Travis Co., Austin, Brackenridge Field Lab, 170 m, 27 Oct 1992, C. R. Nelson #5872 & L, Bezark, 1M, 1F (in copula) (BYUC); VERMONT: “Vt.,” 1M (OSAC); VIRGINIA: Rosslyn, Oct 03, 1M (USNM); Great Falls, Hopk US, C. T. Greene, Oct 22/15, 1M, 2F (USNM); Chain Bridge, 1-Nov-16, C. T. Greene, 1M (USNM); Lorton, 18-Nov-17, W.L. McAtee, 1M (USNM); Falls Church, 17-Oct-15, J. Silver, 1M (USNM); Great Falls, 11-Nov-17, W.L. McAtee, 1M (USNM); Falls Church, 10.22.01, A.N. Caudell, 1M (USNM); Fairfax Co., Springfield, 7402 Reservation Dr., by power line, 38°45.22’N, 77°16.13’W, 14 Oct 2013, R. C. Mower, 2M (BYUC); Montgomery Co., 18 Oct 1983, Blacksburg, Kondratieff, 1M, 1F (in copula) (CSUC); WEST VIRGINIA: Ash, 1M (USNM); WISCONSIN: “ Wis.,” Coquillett, 1M, 1F (USNM); Marathon Co., 18- IX-36, sweeping, H. R. Dodge, 1M (USNM); Shawano Co., Cloverleaf Lks., 16.IX.1938, H. R. Dodge, 4M (USNM); Clintonville, H. R. Dodge, 12.IX.35, 1M (USNM), 17.IX.34, 1M, 1F (USNM). Diagnosis. Males of P. heteroptera are most easily distinguished from New World congeners by the relatively stout gonostylus with the apex minutely truncated or with a slight apical notch (often with a small point developed on the anterodorsal side of the notch) (Figs. 16–20), tergite nine with posterior emargination usually relatively shallow (one-fifth to about one-third the length of the tergite) and broadly U-shaped, but sometimes deeper (up to 2/5) and more V-shaped, ventromedian lobes of gonocoxites weakly to moderately developed (Fig. 20, vml), posteromedian cleft of gonocoxites typically rather broad and shallow (somewhat isosceles trapezoidal in shape) (Fig. 20, vmc), and paramere dome-like, broadly rounded posteriorly, not diamond-shaped (Figs. 16, 20, 38). Remarks. Previously, all “Nearctic” (USA / Canada) specimens of Penthetria have been treated under the name P. heteroptera (e.g., Hardy 1945, 1965b, 1981). The present study recognizes three species of Penthetria in the USA and Canada: P. heteroptera (east of the Rocky Mountains in USA and Canada), P. arizonensis (southern Arizona, USA to Central America), and P. yakima (northwestern USA and sympatric with P. heteroptera throughout Canada). In the USA and Canada, P. heteroptera is most similar to P. yakima from which males can be differentiated by the more robust gonostylus and less diamond-shaped paramere (compare Figs. 38–41). P. heteroptera appears to be allopatric and quite distinct from P. arizonensis within the USA; the former with gonostylus as described above and the later with apex of gonostylus broadly rounded or broadly rounded and culminating in an obtuse point (Figs. 7–8). However, some Mexican and Central American specimens of P. arizonensis have the gonostylus slightly truncate and approximating the terminalia of some P. heteroptera specimens (see Remarks under P. arizonensis). Females of P. heteroptera (Figs. 50–51) are indistinguishable from females of P. yakima (Fig. 56); these two species are sympatric in Canada. However, females may be tentatively determined based on geographic distribution in the USA since, based on material examined, P. heteroptera is the only species known from the eastern USA. Intraspecific Variation. P. heteroptera exhibits a level of intraspecific variation that can create confusion when making identifications. The intraspecific variation described below can sometimes be found even within a single series (same place/date) and therefore does not appear to be clinal (no correlation to geographic distribution) and does not appear to indicate the presence of a cryptic species complex. P. heteroptera males have 8–10 (usually 9) flagellomeres due to the subdivision of the normally more elongate basal or apical flagellomere (variation in number of antennal flagellomeres was found to vary in other Penthetria species as well). Male hind basitarsus relatively slender to robust to slightly swollen and sausage-shaped. The hind tibia ranges from thin and almost parallel-sided to very slightly clavate apically to distinctly clavate apically (the relative degree of swollenness in the tibia and hind basitarsus are correlated; those with more swollen tibia also have a more swollen hind basitarsus). As with many other species in the genus the venation is plastic. R 2+3 can vary up to 50% in length (Figs. 21 a–21b) and cell cua may be closed or open. Wing length ranges from 5.5–8.0 mm (n=8) in males and 6.5–11.0 mm (n=5) in females. Females can have 8–10 (usually 9) antennal flagellomeres. Geographic & Seasonal Distribution. Widespread in the southern Canadian Provinces (British Columbia to New Brunswick; one female Penthetria sp. studied from Nova Scotia) and east of the Rocky Mountains in the United States (Maine south to Florida and west to Colorado) (Map 3). No definitive specimens (gonostylus with apical notch) have yet been studied from south of the USA though the species is known from Texas. Specimens also studied from Montana and Vermont, but not plotted on map due to insufficient label data. The species is also present in Germany (Fitzgerald & Werner 2004) as result of an accidental introduction. See additional Nearctic records (not plotted on Map 3) in Appendix. Flight period July to November with the majority of records from September and October (Table 1)., Published as part of Fitzgerald, Scott J., 2021, Penthetria Meigen (Diptera: Bibionidae): Revision of the New World species and world catalog, pp. 451-500 in Zootaxa 4926 (4) on pages 472-475, DOI: 10.11646/zootaxa.4926.4.1, http://zenodo.org/record/4529512, {"references":["Macquart, J. (1834) Histoire naturelle des insectes. Dipteres. Ouvrage accompagne de planches. Tome Premier. N. E. Roret, Paris, 578 pp. https: // doi. org / 10.5962 / bhl. title. 14274","Werner, D. (1999) The Types of Bibionidae and Pleciidae (Diptera) in the Collection of the Museum fur Naturkunde, Berlin, with Lectotype Designations. Mitteilungen aus dem Museum fur Naturkunde in Berlin / Zoologische Reihe, 1, 51 - 61.","McAtee, W. L. (1921) Notes on Nearctic bibionid flies. Proceedings of the United States National Museum, 60 (11), 1 - 27. https: // doi. org / 10.5479 / si. 00963801.2406","Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547.","Harris, T. W. (1835) VIII. Insects. In: Hitchcock, E., Report on the geology, minerology, botany, and zoology of Massachusetts. Ed. 2. Amherst, Massachusetts, pp. 553 - 602.","Say, T. (1823) Descriptions of Dipterous Insects of the United States. Journal Philadelphia Academia of Science, 3, 9 - 54, 73 - 104.","Evenhuis, N. L. (1997) Litteratura Taxonomica Dipterorum (1758 - 1930). Vols. I & II. Backhuys Publishers, Leiden, 871 pp.","Hardy, D. E. (1965 b) Family Bibionidae. In: Stone, A., Sabrosky, C. W., Wirth, W. W., Foote, R. H. & Coulson, J. R. (Eds.), A catalog of the Diptera of America North of Mexico. Smithsonian Institution Press, Washington D. C., pp. 191 - 196.","Hardy, D. E. (1981) Bibionidae. In: McAlpine, J. F., Peterson, B. V., Shewell, G. E., Teskey, H. J., Vockeroth, J. R. & Wood, D. M. (Eds.), Manual of Nearctic Diptera. Vol. 1. Canada Department of Agriculture Research Branch Monograph 27. Biosystematics Research Institute Ottawa, Ontario, pp. 217 - 222.","Fitzgerald, S. J. & Werner, D. (2004) A key to the Penthetria Meigen (Diptera, Bibionidae) of Europe and the first record of Penthetria heteroptera (Say) from the Palaearctic region. Studia dipterologica, 11 (1), 207 - 210."]}

Penthetria heros Say, 1829 Type Material. Female, “ Mexico ” (Say 1829). The species is unrecognizable from Say’s (1829) original description of a single female from “ Mexico ” and as with many of Thomas Say’s types, the type of this species may be lost or destroyed; the type (s) of P. heros were not found at ANSP, BMNH, MZHF, NHMW, or OXUM. According to a historical account of Say’s collecting trip to Mexico (Papavero & Ibáñez-Bernal 2001 and references therein), “Say, in the company of William McLure, travelled and collected along the old road between Veracruz, Jalapa, Mexico City, and Tacuba, beginning in the autumn of 1827; and on the approach of summer (1828) they returned to the United States.” While this account helps to narrow down the location of the type locality of P. heros, several species of Penthetria occur in this area of Mexico. The species was not mentioned in Hardy’s (1945) work on the Neotropical species though the name was later included in Neotropical catalogs (Hardy 1959, 1966) and other regional lists of Bibionidae (Fitzgerald 2000). Considering that this species is unrecognizable from the original description and the type could not be found, P. heros is here treated as unrecognized (nomen dubium)., Published as part of Fitzgerald, Scott J., 2021, Penthetria Meigen (Diptera: Bibionidae): Revision of the New World species and world catalog, pp. 451-500 in Zootaxa 4926 (4) on page 493, DOI: 10.11646/zootaxa.4926.4.1, http://zenodo.org/record/4529512, {"references":["Say, T. (1829) Descriptions of North American dipterous insects. Journal Philadelphia Academia of Science, 6, 149 - 178.","Papavero, N. & Ibanez-Bernal, S. (2001) Contributions to a History of Mexican Dipterology. Part I. Entomologists and their Works before the Biologia Centrali-Americana. Acta Zoologica Mexicana, New Series, 84, 65 - 173. [2001]","Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547.","Hardy, D. E. (1959) Catalogue of the Neotropical Bibionidae. Acta Zoologica Lilloana, 17, 437 - 476.","Hardy, D. E. (1966) Family Bibionidae. In: Papavero, N. (Ed.), A Catalogue of the Diptera of the Americas South of the United States. Departamento de Zoologia da Secretaria da Agricultura do Estado de S \" o Paulo, S \" o Paulo, pp. 1 - 20.","Fitzgerald, S. J. (2000) Bibionidae. In: Llorente Bousquets, J. E., Gonzalez Soriano, E. & Papavero, N. (Eds.), Biodiversidad, Taxonomia y Biogeograpfia de Artropodos de Mexico. Vol. II. Universidad Nacional Autonoma de Mexico, Mexico, pp. 627 - 634."]}

Genus Penthetria Meigen Amasia Meigen, 1800: 20. Unavailable name; work suppressed for purposes of zoological nomenclature by I.C.Z.N., 1963: 339. Penthetria Meigen, 1803: 264. Type species: Penthetria funebris Meigen, 1804: 104 (by monotypy in Meigen 1804: 104). Threneste Wiedemann, 1830: 618. Nomen nudum. Eupeitenus Macquart, 1838: 88 (also 1838: 84). Type species: Penthetria atra Macquart, 1834: 175 (by monotypy), [examined; BMNH]. Crapitula Gimmerthal, 1845: 330. Type species: Crapitula motschulskii Gimmerthal 1845: 330 (by monotypy). * Bibiopsis Heer, 1849: 228. Type species: Bibiopsis cimicoides Heer, 1849: 229 (designated by Carpenter 1992: 414). * Mycetophaetus Scudder, 1892: 20. Type species: Mycetophaetus intermedius Scudder, 1892: 20 (by monotypy), [examined; MCZC]. [synonymized by Fitzgerald 1999]. Amasia Meigen in Hendel, 1908: 50. Type species: Penthetria funebris Meigen as “ Amasia funebris (Meig.),” by subsequent monotypy in Bezzi, 1911: 39. [synonymized by Evenhuis & Pape 2017]. Pleciomyia Brunetti, 1911: 269. Type species: Penthetria melanaspis Wiedemann, 1828: 72 (by monotypy). Parapleciomyia Brunetti, 1912: 446. Type species: Parapleciomyia carbonaria Brunetti, 1912: 447 (by monotypy). Nomenclatural notes. The genus Bibiopsis Heer, based on a fossil, has historically been treated as a junior synonym of Penthetria (Loew 1868), as a distinct genus (Scudder 1891), and as a junior synomym of a broadly-defined Penthetria (including Plecia Wiedeman and Protomyia Heer; Handlirsch 1907). More recently, Evenhuis (1994, 2014) treated Bibiopsis as a junior synonym of Plecia. However, Heer’s (1849; Plate XV, Fig. 24b) illustration depicts a stout-bodied fly with R 2+3 elongate and subparallel to R 4+5, rather than short and angled, which indicates that this taxon belongs to the genus Penthetria. Generic Diagnosis. The following combination of characters will distinguish adults of extant members of the genus Penthetria from other Bibionidae: Fore tibia simple (without apical mucron or spines), R 2+3 elongate and subparallel to R 4+5, and antennal flagellomeres short, compact. The larva of Penthetria (Fig. 58) can be distinguished from the larva of other bibionids by the combination of the following characters: presence of fleshy tubercles (each abdominal segment with two transverse rows of two tubercles each), posterior spiracle on segment eight, posterior spiracle with a single ecdysial scar, and the mentum not fused to the anterior margin of the cranium or to the posterior margin of the labium (Fitzgerald 2004, Fig. 36b; pm). Pupae (Figs. 59–60) can be distinguished from all other bibionid genera except Plecia by the presence of fleshy tubercles. Discussion supporting generic diagnosis. The generic diagnosis presented above is based on previous phylogenetic and descriptive work on the family Bibionidae (Fitzgerald 2004) and readers are referred there for further information concerning material examined or the broader context from which the diagnosis was developed. The diagnosis is designed for extant species, but reference to problems and exceptions when diagnosing fossil species are provided below. Additionally, characters not necessarily considered diagnostic, but that may be useful in helping to distinguish the genus, are also discussed. The relatively large adults of Penthetria are usually matte-black, with dark wings. They are sometimes confused with some of the large species of tropical Sciaridae, but are easily distinguished from them by the absence of a narrow eye bridge and the presence of vein R 2+3: in Penthetria males are holoptic and females broadly dichoptic (Fig. 1) (though the odd Palearctic species, P. funebris Meigen, has males with eyes that do not quite meet dorsomedially). Adults of Penthetria are distinguished from other Bibionidae by the apically simple fore tibia (Bibioninae all have apex of fore tibia modified into a long mucron or a circlet of shorter spines), relatively short antennae with compact antennal flagellomeres (Hesperinus with flagellomeres elongate), and vein R 2+3 elongate and subparallel to R 4+5 (e.g., Figs. 2, 13, 21b, 23) (R 2+3 absent in Bibioninae). The elongate R 2+3 subparallel to R 4+5 is the character typically employed in keys for distinguishing Penthetria from the similar genus Plecia, which has R 2+3 shorter and more oblique or vertical (Fig. 22). Despite the fact that some species/specimens of Penthetria have R 2+3 approaching the condition found in Plecia (e.g., compare Figs. 21a & 22a) and that the form of R 2+3 is essentially evaluated by gestalt rather than any discrete measurement, the extant species can typically be distinguished in this way with confidence. The use of R 2+ 3 in distinguishing these genera becomes more problematic with fossils, where there is a continuum in the form of R 2+3 between typical Penthetria and Plecia (Collomb et al. 2008, and e.g. see discussion of Penthetria by Skartveit & Nel 2017). It may be useful, based on extant taxa, to develop a more objective way of describing the form of R 2+ 3 in order to help more accurately place fossil taxa. For example, in the wing variation of the extant species presented in Figs. 21–22, Penthetria can be defined by the slope of R 2+3 less than 0.43 and Plecia by the slope of R 2+3 greater than 0.74 (slope defined here as rise/run, where rise = measure of imaginary line between points y and z, and where run = measurement of imaginary line between points x and z (see Fig. 22b)). However, when slope is applied to the continuum of the form of R 2+3 found in fossil species, it is not as clear. For example, if slope is measured for the 15 Plecia and 15 Penthetria wings illustrated by Skartveit & Nel (2017), with a line discriminating Plecia with slope>= 0.50, it would correctly assign alone 27 of the 30 wings (i.e., without evaluating any other aspect of morphology). More variation should be studied before determining whether such a definition could be employed, but utilizing a discrete definition of slope and understanding the breadth of variation in the form of R 2+3 (or other veins) of extant species would undoubtably help to objectify the generic placement of fossil taxa. In addition to differences in the shape of R 2+3, Penthetria and Plecia differ in the form of the male terminalia; the male terminalia in Penthetria are very simple, plesiomorphic (e.g., see Fig. 7), relatively homogenous, with a stout, simple, gonostylus articulating in a socket formed from a relatively elongate gonocoxite. The male terminalia in Plecia are much more complex, show great interspecific variability (see e.g., Hardy 1945, Fitzgerald 1998) and tend to have the tubular, gonostyus-socket-portion of the gonocoxite greatly shortened. However, this is less true in fossil specimens. As Skartveit and Nel (2017) point out, the male terminalia of some fossil Plecia are very plesiomorphic and Penthetria -like (e.g., see Collomb et al. 2008). Additionally, Penthetria has subtle parapsidal sutures (longitudinal sutures on the mesonotum corresponding to the position of dorsocentral setae), while they are often present as distinct grooves in Plecia. Females of the two genera can be also be distinguished by Penthetria having two segmented-cerci and Plecia with one-segmented cerci—though some fossil Plecia (e.g., P. clavifemur Skartveit 2009) have been described with two-segmented cerci. It is also noteworthy that Penthetria and the bibionid genus Hesperinus cannot be reliably distinguished based on wing venation alone (Skartveit 2009), which is critical in situations where the fossil specimen is represented only by a preserved wing. In fossils where more than the wing has been preserved, Penthetria has shorter antennae, with more compact flagellomeres and tends to be more stout-bodied, with shorter legs than Hesperinus. Additionally, males of Penthetria are typically holoptic while both sexes of Hesperinus are dichoptic. See also “Intraspecific Variation” (below) with respect to the delimitation of fossil species. Classification and phylogenetic placement. Some studies have placed Penthetria, along with the genus Plecia, in the subfamily Pleciinae of Bibionidae (e.g., Hardy 1981, Blaschke-Berthold 1994) or in the separate family Pleciidae (e.g., Krivosheina 1986) based, in part, on similarities in the larvae of these genera including the “clearly separated frons and clypeus, presence of an additional lobe of the maxillae, and primitive spiracles” (Krivosheina 1969) or musculature of the male terminalia (Ovtshinnikova 1994). More recent morphological phylogenetic studies, however, have not supported these classifications, instead placing Penthetria in its own subfamily (Penthetriinae), which is considered the most basal lineage of bibionids after Hesperinus (Hesperinus + (Penthetria + (Plecia + Bibioninae))) (Pinto & Amorim 2000, Fitzgerald 2004). This latter hypothesis was not corroborated by the molecular study by Ševčík et al. (2016), which found Penthetria (along with Hesperinus) to be less basal within the bibionid family tree (Bibioninae + (Plecia + (Penthetria + Hesperinus))). Skartveit & Ansorge (2020) propose placing Hesperinus and Penthetria together in the subfamily Hesperininae based on the Ševčík et al. (2016) study, which finds these two genera to be sister taxa. Further work is needed to reconcile the contradictory hypotheses of these morphological and molecular studies. Characters to support the monophyly of Penthetria are sparse. Fitzgerald (2004) suggested the larval mesothorax with two pseudosegments as a synapomorphy, but so few larvae are known that this character will have to be further vetted as the larvae of more species are discovered. Comments on generic description. The adult and larval generic description provided below is based, in part, on previous phylogenetic and descriptive work on the family Bibionidae (Fitzgerald 2004) and readers are referred there for further discussion concerning homology of structures, material examined, and the broader context from which the description was developed. Examination of all the New World species, as well as a small number of species from the Palearctic and Oriental bioregions were examined. A sclerotized aedeagus is considered absent in Penthetria by Fitzgerald (2004) and it has been presented this way in the generic description (below). Blaschke-Berthold (1994, Fig. 6) suggests that the aedeagus is fused with the parameres in this genus but whether it is absent or indistinguishably fused, a distinct, separate aedeagal sclerite cannot be identified. Sperm transfer in Penthetria is apparently not achieved via an intromittent organ, but probably by spermatophore (Blaschke-Bethold 1994), as is known in some other Bibionidae (Leppla et al. 1975). Larvae are known for only two species of Penthetria. Aspects of the larva of the Palearctic species P. funebris have been illustrated in various papers—mandible (Hennig 1948), habitus and posterior spiracle (Krivosheina 1962), habitus, posterior spiracle, mandible, and labium (Krivosheina & Mamaev 1967), and labium and maxilla (Fitzgerald 2004). The egg, larva, and pupal stages of P. japonica Wiedemann were described and illustrated by Yuan et al. (2015). The larval description below is based on the study of these two species. Generic description. Adult: Small to moderately large flies 4.0-11.0 mm. Head: Male head dorsoventrally compressed; in dorsal view, slightly wider than long, oval-shaped. Head and antennae black to brown. Male with almost entire dorsal surface of head occupied by broadly holoptic compound eye (Fig. 1), except P. funebris, with compound eyes narrowly separated dorsally by longitudinal strip of frons approximately subequal in width to antennal flagellum. Male compound eye strongly divided into larger dorsal region and smaller ventral region; dorsal region usually lighter in color than ventral region and with larger ommatidia. Division between dorsal and ventral regions of compound eye often distinguished by distinct narrow longitudinal step (the dorsal region of the eye is often taller than the ventral region of the eye; where the dorsal and ventral regions meet laterally, a short step, curb, or groove is often visible as in Fig. 12). Division not marked by narrow, longitudinal, shining, sclerotized band; smooth, triangular area devoid of ommatidia also absent. Female head dorsoventrally compressed, slightly wider than long. Female compound eye round or oval in shape, convex, dichoptic (Fig. 1), broadly separated by frons. Female compound eye with inconspicuous, slight longitudinal depression dividing compound eye, but lacking any difference in size of ommatidia or color between dorsal and ventral regions. Compound eye of both sexes bare or clothed with minute, stiff, or very elongate hairs. Ocellar tubercle well developed and prominent in males, moderately to weakly developed in females. Both sexes with three ocelli arranged in small, equilateral triangle. Female with small tubercle or longitudinal ridge just posterior to antennal sockets. Male frons reduced to small, triangular region between anterior margin of compound eye, posterior margin of antennal sockets bearing minute tubercle (or a minute pit in P. funebris). Sclerotized rostrum not produced, oral margin somewhat ventral in position. Antenna located anteriorly along oral margin, with 7–10 short, stout flagellomeres. Flagellomeres slightly broader than long, except most basal flagellomere, about two times as long as subsequent flagellomere. Pedicel and flagellomeres with subapical ring of short setae and numerous dense, minute, appressed setae. Apical flagellomere slightly more elongate than preceding flagellomere, with rounded point apically. Maxillary palps with five segments; basal segment minute, third segment thickened with dorsal, diagonal sensory pit with dense, minute, specialized setae; apical palpomere slender, more elongate than previous palpomeres. Clypeus broader than long, never elongate. Head entirely sclerotized ventrally. Thorax (Fig. 3): Precoxal-bridge complete. Basisternum present, presternum absent. Dorsum of thorax smooth, matte, often with thick dark pruinosity, usually black, dark brown, anteriorly black and posteriorly orange, or rarely entirely orange, as in P. indica (Brunetti). Parapsidal sutures subtle and not distinct as in some Plecia. Dorsum of thorax with dense, short, stiff to very elongate hairs, laterally, anteriorly, and in dorsocentral rows posteriorly. Thoracic pleura black to dark brown. Males with minute to moderately long hairs on metakatepisternum, and dorsal half of katepisternum. Anepisternum bare or with cluster of hairs at posterior margin. Meron, laterotergite, and mediotergite bare. Female thoracic pleura generally less hairy than male. Legs: Legs black to dark brown. All legs with five tarsomeres, simple tarsal claws, pulvilli and pulvilliform empodia. Anterior coxa short and not reaching ventral edge of katepisternum; reaching about half length of katepisternum in lateral view, usually with elongate hair. Fore femur relatively slender and more elongate; not short and swollen. Fore tibia elongate, slender, apex unmodified, outer edge not developed into a mucron. Fore tibia distally with a single, short spur. Middle legs unremarkable; with two apical tibial spurs. Hind legs with hind femur swollen apically to more slender and only slightly enlarged apically. Hind tibia slender or swollen apically. Inner surface of hind tibia without elongate field of small, round, black, specialized sensilla. Spurs of hind tibia slender, apically acute, subequal in length, or ventral spur slightly more elongate than dorsal spur. In males, hind tarsomeres vary in shape, from slender, elongate, parallel-sided to slightly swollen and sausage-shaped. Female tarsomeres never swollen; slender to robust. Halter black. Wing (Figs. 2, 13): Length, 4.5-12.5 mm, elongate, reaching tip of abdomen, except brachypterous and distinctly shortened in males of P. funebris. Wing brown to blackish fumose. Costal cell often darker than remainder of wing in taxa with fumose wings. Wing color solid or with grade in intensity, but without distinct markings. Pterostigma oval, usually brown to black. Anterior wing veins typically darker than posterior veins. Wing without macrotrichia, with microtrichia. Anal lobe well developed. Costa ends at or just beyond R 4+5 (not shortened or thickened as Enicoscolus Hardy). Subcosta long, complete. Radius without horizontal microstriations. Rs furcate; R 2+3 present, relatively elongate and subparallel to slightly oblique to R 4+5; base R 2+3 often arising at right angle to R 4+5 then sharply bent in direction of wing tip. Base of R 2+3 sometimes with sub-basal stump (appendix) (e.g., P. appendicula Hardy; Fig. 2). R 2+3 branches from R 4+5 from slightly basal to, even with, or distinctly distal to, r-m crossvein. Length of r-m crossvein much shorter than base of Rs. Posterior end of r-m meeting stem of medial fork (M 1+2) or more distally, connecting directly to M 1 (e.g., P. japonica Wiedemann; Hardy & Takahashi 1960, Fig. 2b). Three branches of M present (M 1, M 2, and M 4). Base of M 4 crossvein-like. CuA and CuP present, reaching wing margin, sometimes meeting distally forming closed cell cua. A 1 short, weak; not extending beyond the small fold at the base of anal lobe. Abdomen: Black to dark brown, with short to elongate hairs. Male abdomen elongate, gradually tapered posteriorly; female abdomen much stouter. Male spiracles 1–7 located laterally on abdominal pleura, except spiracle eight, either absent or, if present, a remnant dorsolaterally at membrane between tergites eight and nine (e.g., P. funebris). Males with tergites and sternites 1–8 unmodified, females with tergites 1–8 and sternites 1–7 unmodified. Male terminalia (Figs. 4–11, 14–20, 24–29, 33–45): Terminalia slightly dorsoflexed, not rotated. Posterior margin of tergite 9 (epandrium) shallowly to deeply (nearly dividing tergite) emarginated (“epandrial cleft”) medially. Epandrial cleft often U-shaped, with lobes at sides of posterior edge of epandrium (epandrial lobes) typically broad, rounded, sometimes more triangular in shape apically. Anterior edge of epandrium sometimes with a shallow to moderate medial emargination. Gonocoxites fused to sternite 9 (hypandrium) into a continuous genital capsule (synsternogonocoxite). Hypandrium distinguishable only by narrow, strap-like thickening ventrally and sometimes a slight medial seam. Posteromedian margin of synsternogonocoxite sometimes with median hump, a median cleft (ventromedian cleft, Fig. 20, vmc), and/or a pair of weak to strong lobes (ventromedian lo, Published as part of Fitzgerald, Scott J., 2021, Penthetria Meigen (Diptera: Bibionidae): Revision of the New World species and world catalog, pp. 451-500 in Zootaxa 4926 (4) on pages 453-460, DOI: 10.11646/zootaxa.4926.4.1, http://zenodo.org/record/4529512, {"references":["Meigen, J. W. (1800) Nouvelle classification des mouches a deux ailes (Diptera L.) d'apres un plan tout nouveau. Perronneau, Paris, 40 pp. https: // doi. org / 10.5962 / bhl. title. 119764","Meigen, J. W. (1803) Versuch einer neuen GattungsEintheilung der europaischen zweiflugligen Insekten. Magazin fur Insecktenkunde, 2, 259 - 281.","Meigen, J. W. (1804) Klassifikazion und Beschreibung der europaischen zweiflugligen Insekten (Diptera Linn.). Erster Band. Abt. I & II. 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Penthetria arizonensis Fitzgerald n. sp. (Figs. 7–8, 32, 52–53, Map 2) Type Material. Holotype: Male, point-pinned (USNM), USA, ARIZONA, Cochise Co., near Benson, 21 Sept. 1985, J. Jenkins coll. [white label] / HOLOTYPE, Penthetria arizonensis Fitzgerald [red label]. Terminalia dissected. Paratypes: USA: ARIZONA: Same data as HT, 3M (CSUC); Ramsey Cyn. 5200’, 15 mi S. Sierra Vista, Huachuca Mts. 12. VI.1967, R. F. Sternitzky, 2M (CNCI); Ramsey Cyn., 5000’, 15 mi S. Sierra Vista, Huachuca Mts., Malaise trap, Sternitzky, 3. VI.1967, 1M (CNCI), 4. VI.1967, 1M (CNCI); Santa Cruz Co., Duquesne Rd. at jct. FS4675, 17–30 Sept 2018, V-FIT, 31.3771°, -110.7593°, W.B. Warner, 4M (2 SFC, 2 ASUT); Cochise Co., Bisbee, 1429 Franklin St., 1585 m, A.S. Menke, MT, 31°24’23”N, 109°55’57”W, 28.ix–1.x.2012, 3M (SFC), 2–7.x.2012, 3M (SFC), 10–16.ix.2012, 6M, 1F (SFC), 16–24.ix.2012, 5M (SFC), 1M (BYUC). Additional Material examined. GUATEMALA: GUATEMALA: Puerta Parada, 1850 m, 7–14 IX 2013, J.C. Schuster, 1M (UVGC), 22–28 Aug 2015, 1M, 2F (SFC); COSTA RICA: SAN JOSÉ: San Pedro de Montes de Oca, 11.X.33, C.H. Ballou, on cabbage, C. R. No. 1872, 1M (USNM); MEXICO: CHIAPAS: 7200 ft., S. Crist. las Casas, 10 June 1969, Malaise Trap, 3M (CNCI); MEXICO CITY: D.F., Sept ’98, 2M (USNM); MICHOACAN: El Salto, 5 mi. W., X.9.1964, A.E. Michelbacher, 1M, 1F (in copula) (SFC); MORELOS: 6 mi E Cuernavaca, 12 Sept 1973, W.J. Hanson, B.A. Haws, 2M, 2F (NHMLA); Cuernavaca, 9-28-57, R. & K. Dreisbach, 1M (CNCI); PUEBLA [?]: Puebla Rd., km 63, x-2-57, Dreisbach, 4M (CNCI); SONORA: Alamos Rancho Acosta, MT in dry wash, tropical deciduous forest, 28.ix–3.x.2006, M.E. Irwin, 395 m, 27°01.57N, 108°55.37W, 1M (SFC); 27 km NE Alamos, Rancho Santa Barbara, La Posa de Encino Boludo, MT at isolated water hole in oak woodlands, 20–27.ix. 2008, 1242 m, M.E. Irwin & F.D. Parker, 27°06.27N, 108°43.86W, 1M (SFC); 37 km NE Alamos, Rancho santa Barbara, malaise, dry wash in oak-pine forest, 2–6.x.2006, M.E. Irwin, 1295 m, 27°06.60N, 108°43.91W, 1M (SFC); ZACATECAS: Rio Grande, X-18-68, G.E. Bohart, 1M (NHMLA). Description (based on specimens from Arizona, USA). Male (Fig. 32). Body length: approx. [5.0] mm. Head. Black. Compound eye holoptic, covering virtually all of dorsal and lateral surface of head, with lateral longitudinal step dividing upper and lower portion of eye. Eyes nearly bare, with some very minute, very sparse ommatrichia present.Antennae black, eight to nine flagellomeres with black setae. Flagellomeres wider than long except first and ultimate flagellomeres about as wide as long. Three ocelli on well-developed tubercle. Thorax matte dark brown to blackish with light brown highlights on humeral ridge and posterior portions of pleurae, sometimes with mesonotum dark brown with three broad black longitudinal stripes, the median stripe reaching the pronotum and the lateral stripes truncated anteriorly. Thorax largely bare except fine short dark hairs on mesonotum in broad dorsocentral rows and a few hairs anterolaterally. Scutellum bare or with a few sparse short fine dark hairs and middle of katepisternum and metepisternum with long dark hairs. Legs. Slender, entirely dark brownish-black with dense short dark appressed hairs. Hind femur slightly thickened (clavate) on apical third. Hind tibia slender elongate gradually thickened apically. Hind basitarsus robust to slightly swollen and sausage-shaped, about four times as long as wide. Wings. Arizona specimens ca. [5.0]–6.0 mm (n=7) and Mexican and Central American specimens slightly larger 7.0–8.0 mm (n=3), brown fumose, darker costally. Veins brown, pterostigma concolorous with membrane. Venation as in other members of the genus. Sc long, complete. R 2+3 elongate, subparallel to R 4+5, without basal appendix. CuA and CuP apically convergent, sometimes reaching wing edge independently (not meeting), sometimes meeting prior to wing edge forming a closed cell cua (Fig. 32). Abdomen. Dark brown to black. Terminalia (Figs. 7–8) dark brown to black. Tergite nine broader than long, posterior margin with shallow emargination reaching about one-third to slightly less than one-half the depth of sclerite. In dorsal view, gonocoxites dorsoapically without small apically rounded medially-projecting lobe just dorsal to gonostylar socket (as found in P. dolichopeza). In ventral view, posterior edge of medially fused gonocoxites + hypandrium with a broad shallow median cleft bounded by a pair of weakly (Fig. 8) to moderately (as in Fig. 20) developed lobes. In dorsal and ventral views, gonostylus stout, gently curved, apically broadly rounded or broad and culminating in a very obtuse point medially (in one paratype from Arizona point is more distinctive and in some Mexican and Central American specimens the apex of gonostylus slightly truncate due to a flat area between the median point and a minutely developed dorsoapical point). Paramere indistinguishable from P. heteroptera; in dorsal and ventral views fused parameres projecting from out of genital capsule, shiny brown heavily sclerotized dome-like, often with a small cleft apically. Divergent horn-like lobes of paramere present, but ventral and subapical in position and more confluent, with the dome-like contours of the paramere rather than strongly projecting caudally and ventrally as found in P. mexicana. Cerci fleshy, apically rounded with setae. Female. Similar to male. Body about 5.0 mm and wing 5.5–6.0 mm (n=2; Arizona). Eyes dichoptic. Antennae with unknown number of flagellomeres (Arizona female missing antennae). Female hind basitarsus slender elongate. Abdomen stout. Terminalia (Figs. 52–53): Tergite nine present as narrow, transverse strap, medially subdivided into two sclerites; more produced ventrolaterally. Tergite ten minute, nearly hyaline, longitudinally elongate, lying between bases of cerci. Cerci two-segmented, apical segment relatively short. Subgenital plate (= sternite eight) large, longitudinally subdivided, with posterior margin with a pair of broad lobes. Y-shaped genital fork present. In addition to genital fork, a minute pair of sclerites present between the posterior margin of the subgenital plate and the anterior margin of sternite ten. Sternite 10 present, posteriorly broadly rounded. Three rounded, sclerotized, capsule-like, spermathecae present. Diagnosis. Males of P. arizonensis can be distinguished from the very similar species P. heteroptera and P. mexicana by the gonostylus without an apical notch and apex of paramere broadly rounded (see detailed discussion and comparsion of these three species in “Remarks”). Remarks. Historically all specimens of Penthetria from the USA were considered to be P. heteroptera. However, specimens from southern Arizona (previously determined as P. heteroptera by various workers including the present author) represent a distinct species (P. arizonensis). Within the USA, allopatric populations of P. heteroptera (East of the Rocky Mountains) and P. arizonensis (southern AZ) are easily distinguished based on differences in the apex of the gonostylus; P. heteroptera has the apex of the gonostylus minutely truncate, the truncate portion often slightly notched (Figs. 16–20), with the anterodorsal side of the notch often produced into a small point, while the Arizona specimens studied all have the apex of the gonostylus broadly rounded or broadly rounded and culminating in an obtuse median point (Figs. 7–8). While these morphological differences and the correlated allopatric distribution seem to indicate two distinct species, the study of Mexican and Central American specimens attributed to P. arizonensis revealed variation in the apex of the gonostylus (the broadly rounded apex is sometimes very minutely truncate (as in Fig. 19), though never notched), which make these specimens, in some cases, indistinguishable from some specimens of P. heteroptera from the eastern USA that have only a very slight truncation and lack a notch. It is unclear whether the slightly truncate gonostylus in P. arizonensis is simply intraspecific variation or if there is some integration between the two species, but as no definitive specimens of P. heteroptera (gonostylus with an apical notch) have been studied from south of the USA (either in this study or by Hardy (1945)) and the fact that P. mexicana also sometimes has the gonostylus slightly apically truncate, the conclusion adopted here is that of intraspecific variation. Regardless of this inability to reliably distinguish some Mexican and Central American specimens from some eastern North American specimens, the two forms have been treated as distinct species; P. heteroptera east of the Rocky Mountains in USA and Canada and P. arizonensis from southern Arizona, USA to Central America. P. arizonensis likely represents the species identified by Hardy (1945) as P. nigerrima (Bellardi), which was originally described from Mexico (see “Unrecognized Species of Penthetria ” below). In addition to P. heteroptera, P. arizonensis is also very similar to P. mexicana, as they share the apically broadly rounded gonostylus which sometimes culminates in an obtuse median point or may be apically truncate. P. arizonensis is most easily distinguished from P. mexicana by the structure of the paramere; in P. mexicana the pair of divergent horn-like lobes (whale-tail-like structure) often appears apical (most posterior) when the paramere is in dorsal or ventral views (Figs. 24–26, 28), while in P. arizonensis the divergent lobes of the paramere do not appear apical when viewed ventrally or dorsally, are more ventral and subapical in position, and are more confluent with the dome-like contours of the paramere rather than strongly projecting caudally (Figs. 7–8). In some specimens of P. mexicana where the divergent lobes of the paramere are slightly less projecting (Fig. 28) or even slightly out of view from a strict dorsal view (Fig. 29), the apex of the paramere is slightly laterally compressed making it narrow and ridge/nubbin-like apically (Fig. 29), whereas the paramere of P. arizonensis is broadly rounded (Fig. 7) and often has a small groove apically (as in Figs. 16 & 20); the paramere of P. arizonensis is indistinguishable from that of P. heteroptera. Females of P. arizonensis are indistinguishable from females of P. heteroptera, P. mexicana and P. yakima, but they can be distinguished from P. appendicula and P. distincta, which have more slender posteromedian lobes on sternite eight and the second segment of the cerci more elongate (Figs. 46–48), and from P. neonigrita, which has a more strongly developed tergite nine (Fig. 54). Etymology. The specific epithet is taken from the type locality, Arizona, USA. Geographic & Seasonal Distribution. Southern Arizona, USA south to Central America (Map 2). Seasonal distribution summarized in Table 1., Published as part of Fitzgerald, Scott J., 2021, Penthetria Meigen (Diptera: Bibionidae): Revision of the New World species and world catalog, pp. 451-500 in Zootaxa 4926 (4) on pages 463-467, DOI: 10.11646/zootaxa.4926.4.1, http://zenodo.org/record/4529512, {"references":["Hardy, D. E. (1945) Revision of Nearctic Bibionidae, including Neotropical Plecia and Penthetria (Diptera). Kansas University Science Bulletin, 30, 367 - 547."]}