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Velásquez-Rodríguez, Karen, Lin, Xiao-Long, Sánchez-Vendizú, Pamela, Loayza-Muro, Raúl, Huamantinco, Ana, Prat, Narcís (2023): DNA Barcode of symbiotic chironomids: Findings in the genus Symbiocladius (Diptera: Chironomidae). Zootaxa 5319 (1): 48-56, DOI: 10.11646/zootaxa.5319.1.3, URL: http://dx.doi.org/10.11646/zootaxa.5319.1.3

Symbiocladius wygodziskyi (Roback, 1965) The morphological analysis of the larval stage of S. wygodzinskyi agrees with the character descriptions given in Kieffer (1925), Roback (1965) and Gonser & Spies (1997) for mentum with 5–6 lateral teeth and the proximal tooth of the mandible long and slender. On the other hand, mature larvae have curved thoracic horns, gradually narrowing from the wide base to acute apex. Moreover, molecular analysis also supports morphological results. More detailed results are described below. Larva Body length: 1.94–2.33 mm (n = 2), maximum diameter: 0.36– 0.29 mm (n = 2). Body with yellowish and slightly whitish coloration on the sides (Fig. 2A–B). Cephalic sclerotized capsule triangular in shape, 134.9–147.7 μm (n = 2) long, with a maximum width at the base of 135.3–139.3 μm (n = 2). Non-visible eye spots (Fig. 2D). Antenna with 5 segments, 14–18.1 μm (n = 3) long. Mandible, length: 25–28.7 μm (n = 4), heavily sclerotized, with two internal teeth, the more distal tooth is thicker than the proximal one. Mentum translucent not heavily sclerotized as the mandibles, wide central tooth, with 5–6 very acute lateral teeth at distal end. Short anterior prolegs with more than 90 hooks, which present one apical tooth and several internal teeth. Posterior prolegs with 19 hooks, these hooks do not have internal teeth. Pupa Mature larvae already display pupal features, including sclerotized thoracic horns. Body length: 3.15–4.10 mm (n = 2), maximum width (thorax): 1.02–1.03 mm (n = 2). The body exhibits a gray coloration, with pale or light-colored spots mainly in the ventral and lateral region of the thorax. (Fig. 2C). Thoracic horn curved, tapering towards the distal end until ending in a very sharp projection, 127.4–143.3 μm (n = 4) total length, base of the projection is 23.7–35.6 μm (n = 4) wide (Fig. 2E). Abdomen has filiform spines on the tergites. Ecological notes Specimens were found living on nymphs of Leptophlebiidae (Ephemeroptera). Larvae in process of pupation build a membranous sheath and were positioned from the II thoracic segment to the V abdominal segment of the host. The position of the larva on the host can be with the head forward or backward (Fig. 2A–B). There is no indication that Symbiocladius (A.) wygodzinskyi feeds on the hemolymph of its host. Finally, the host nymphs had very small translucent wing patches of the same size. Therefore, it was not possible to appreciate the effect of the commensal on the development of the wing patches. Distribution: Department of La Libertad. Province: Sánchez Carrión. Municipality: Sarín. Chusgón River (a tributary of the Marañón River), 7°58’18.195” S, 77°57’51.962” W, m.a.s.l. Department: Apurímac. Province: Cotabambas. Municipality: Cotabambas. Anchapillay River (tributary of the Apurímac River), 14°2’57.8106” S, 72°24’6.8148” W, 4234 m.a.s.l. Department: Áncash. Province: Huaraz. District: Independencia. Churup River 9°29’14.70” S; 77°25’58.92” W, 4183 m.a.s.l. (Fig. 1) DNA barcode analyses The NJ tree based on partial COX1 gene shows two well supported major clades. The first clade is composed by species of Symbiocladius (99.5% of bootstrap support) from China and the second clade is formed by the species Symbiocladius (Acletius) wygodziskyi, the genera Nanocladius spp. and Epoicocladius spp. and Epoicocladius spp. (92.5% of bootstrap support) (Fig. 3). This evidences that Symbiocladius does not form a monophyletic clade for COX1 genetree. These two clades recovered from Symbiocladius agree with the currently proposed subgenera, Symbiocladius and Acletius, presenting a genetic distance of 24.8±2%. The first clade of Symbiocladius includes species of the subgenus Symbioclaidus: S. (S.) rithogenae and one not described yet, S. (S.) sp. 1XL that are genetically differentiated in 17.2±1.7% (Table. 1). On the other hand, the second clade of Symbiocladius include the sequences generated in this study for Symbiocladius (A.) wygodziskyi, which differ from 19.4% to 26.4% with respect to the other species of Epoicocladius, and Nanocladius (Table. 1).

Supplemental material, sj-pdf-3-imj-10.1177_10815589231152823 for A high triglyceride-glucose index associated with adverse cardiovascular events in patients with type 2 diabetes mellitus and chronic total occlusion after percutaneous coronary intervention by Xiao Long Lin, Qiu Yu Li, Dong Hui Zhao, Jing Hua Liu and Qian Fan in Journal of Investigative Medicine

Rheotanytarsus pinderi Yao & Liu sp. n. (Figs. 1B, 3A–E) Type material. Holotype: male (NKU: LGS79), China, Qiandongnan Miao and Dong Autonomous Prefecture, Leigongshan National Nature Reserve, Fangxiang, Getoucun country, 15–25. i. 2020, malaise trap, leg. H.J. Yu. Etymology. Named after Prof. Clive Pinder, for his outstanding contribution to the knowledge of Chironomidae; noun in nominative case. Diagnosis. The species can be distinguished from known species of Rheotanytarsus by the following combination of characters: antenna with 13 flagellomeres, and AR 0.18; thorax with brownish-yellow stripes and postnotum dark brown; tergite IX approximately triangular; superior volsella oval, with a knob-like structure; median volsella with apically broader stem and forked apical setae; gonostylus gradually tapered and curved apically, with rounded apex. Description. Adult male (n = 1) Total length 2.21 mm. Wing length 1.44 mm. Total length/wing length 1.54. Wing length/length of profemur 2.35. Colouration (Fig. 1B). Thorax pale brown with brownish-yellow stripes and postnotum dark brown, legs pale brown with apical portion of femur slightly darker, and abdomen pale yellow. Head. Antenna with 13 flagellomeres, ultimate flagellomere 92 μm long. AR 0.18, relatively small. Temporal setae 7. Clypeus with 18 setae. Tentorium 83 μm long, 11 μm wide. Palpomere lengths (in μm): 37, 29, 62, 87, 148; Pm5/Pm3 2.39. Third palpomere with 2 sensilla clavata distally. Thorax. Dorsocentrals 9; acrostichals 9; prealar 1. Scutellum with 6 setae. Halteres with 7 setae. Wing (Fig. 3A). VR 1.78. Brachiolum with one seta, Sc bare, R with 13 setae, R 1 with 26 setae, R 4+5 with 57 setae, RM with one seta, M 1+2 with 44 setae, M 3+4 with 28 setae, false vein with 79 setae, Cu with 12 setae, Cu 1 with 21 setae, PCu with 49 setae, An with 24 setae, remaining veins bare. Cell r 4+5 with c. 250 setae, m with 3 setae, m 1+2 with c. 250 setae, m 3+4 with c. 100 setae, cu+an with c. 150 setae. Legs. Tibia and all tarsomeres of fore leg used for DNA extraction. Combs of mid tibia 24 μm wide with 27 μm long spur, and 33 μm wide with 25 μm long spur; combs of hind tibia 32 μm wide with 40 μm long spur, 36 μm wide with 34 μm long spur. Tarsomere 1 of mid leg with three sensilla chaetica. Lengths (in μm) and proportions of legs as in Table 2. Hypopygium (Figs. 3 B-E). Tergite IX 66 μm long, with eight median setae at base of anal point; anal tergal bands well separated and of V-type with a small tilt angle. Anal point 33 μm long, with slightly swollen apex, bearing five lateral setae on each side; crests somewhat parallel and nearly reaching apex of anal point. Transverse sternapodeme 31 μm long, with tiny oral projections. Phallapodeme 78 μm long. Gonocoxite 95 μm long. Gonostylus 81 μm long, gradually tapered and curved apically, with rounded apex. Superior volsella (Fig. 3D) 36 μm long, oval, with two anteromedian setae, and with two (left) or three (right) thicker setae on a knob-like structure on dorsal. Digitus thumb-like, without seta. Median volsella (Fig. 3E) 126 μm long, well reaching beyond apex of inferior volsella, with long and foliate setae apically, some forked; stem covered with simple setae, slightly curved and apically broaden. Inferior volsella 58 μm long, curved and gradually swollen, with microtrichia. HR 1.17. HV 2.72. Female and immatures. Unknown. Remarks. The new species resembles Rheotanytarsus oss Cranston, 1997 by having similar shapes of superior volsella and median volsella, but can be separated from the latter species by the following combination characters: gonostylus curved apically, tergite IX approximately triangular, anal crests parallel-sided, whereas gonostylus not curved, tergite IX with rounded margin, anal crests of V-type in R. oss., Published as part of Liu, Wen-Bin, Yao, Yuan, Chang, Tong, Yan, Chun-Cai & Lin, Xiao-Long, 2022, Contribution to the knowledge of Rheotanytarsus pellucidus species group from China (Diptera, Chironomidae): three new and one newly recorded species, pp. 145-156 in Zootaxa 5188 (2) on pages 149-151, DOI: 10.11646/zootaxa.5188.2.4, http://zenodo.org/record/7087541, {"references":["Cranston, P. S. (1997) Revision of Australian Rheotanytarsus Thienemann & Bause (Diptera: Chironomidae), with emphasis on immature stages. Invertebrate Systematics, 11, 705 - 734. https: // doi. org / 10.1071 / IT 96025"]}

Key to known adult males of the Rheotanytarsus pellucidus species group ( Based on the key in Kyerematen et al. 2000) 1. Median volsella relatively short, not reaching apex of inferior volsella........................................... 2 - Median volsella very long, extending beyond apex of inferior volsella........................................... 3 2. Inferior volsella curved and sharply pointed at apex; superior volsella widest at apex; median volsella with wide, nearly circular apical plate; Australia................................................... Rheotanytarsus flabellatus Glover, 1973 - Inferior volsella not apically pointed, superior volsella elongated with bluntly rounded apex; median volsella with relatively narrow, ovoid apical plate; Thailand................................. Rheotanytarsus thailandensis Moubayed, 1990 3. Median volsella with distal setae fused into narrow plate with or without apical points; Japan........................................................................................ Rheotanytarsus yufualbus Sasa & Suzuki, 1991 -. Median volsella with lamelliform setae, but never fused into plate............................................... 4 4. AR relatively large and about 0.75; superior volsella with microtrichia; Europe, north Africa, Canada, America, Mongolia..................................................................... Rheotanytarsus pellucidus (Walker, 1848) - AR relatively small and less than 0.60; superior volsella without microtrichia...................................... 5 5. Superior volsella with knob-like structure; stem of median volsella apically broader................................ 6 - Superior volsella without knob-like structure; stem of median volsella tapered or with equal width..................... 7 6. Gonostylus curved apically; anal crest nearly parallel-sided; tergite IX triangular... Rheotanytarsus pinderi Yao & Liu sp. n. - Gonostylus not curved apically; anal crest of V-type; tergite IX with rounded margin; Australia, China, Thailand................................................................................... Rheotanytarsus oss Cranston, 1997 7. Anal crest basally fused to form an arc.................................... Rheotanytarsus tamasecundus Sasa, 1980 - Anal crest basally not fused............................................................................. 8 8. Anal point very thin apically; anal crest reduced and not visible; China........ Rheotanytarsus apiculus Wang & Guo, 2004 - Anal point not thin apically; anal crest visible and evenly developed............................................. 9 9. Inferior volsella without microtrichia; cell m with about 20 setae; Ghana, China.................................................................................................. Rheotanytarsus buculicaudus Kyerematen, 2000 - Inferior volsella with microtrichia; setae number of cell m less than 5........................................... 10 10. Thorax pale or pale brown without spots; Thailand.......................................................... 11 - Thorax pale yellow with dark brown spots and postnotum dark brown; China..................................... 12 11. Anal tergal bands nearly horizontal; 13th flagellomere of antenna extremely short, AR only 0.06...................................................................................... Rheotanytarsus minusculus Kyerematen, 2000 - Anal tergal bands of V-type; 13th flagellomere of antenna relatively long, AR 0.39–0.48........................................................................................ Rheotanytarsus contrerasi Andersen & Saether, 2000 12. Anal tergal bands fused; stem of median volsella with foliate setae basally; gonostylus with rounded apex................................................................................ Rheotanytarsus vallenduuki Yao & Liu sp. n. - Anal tergal bands separated; stem of median volsella without foliate setae; gonostylus with pointed apex...................................................................................... Rheotanytarsus ashei Yao & Liu sp. n., Published as part of Liu, Wen-Bin, Yao, Yuan, Chang, Tong, Yan, Chun-Cai & Lin, Xiao-Long, 2022, Contribution to the knowledge of Rheotanytarsus pellucidus species group from China (Diptera, Chironomidae): three new and one newly recorded species, pp. 145-156 in Zootaxa 5188 (2) on page 155, DOI: 10.11646/zootaxa.5188.2.4, http://zenodo.org/record/7087541, {"references":["Glover, B. (1973) The Tanytarsini (Diptera: Chironomidae) of Australia. Australian Journal of Zoology, Supplement, 23, 403 - 478. https: // doi. org / 10.1071 / AJZS 023","Moubayed, Z. (1990) Chironomids from running waters of Thailand: Description of Rheotanytarsus thailandensis sp. n. and Tanytarsus thaicus sp. n. (Dipt., Chironomidae). Hydrobiologia, 203, 29 - 33. https: // doi. org / 10.1007 / BF 00005610","Sasa, M. & Suzuki, H. (1991) The Chironomids of the Jyoganji River Hayatsuki River and Katakai River. Pt. 5. Studies on the chironomids of the Aso National Park Area, Kyushu. Toyama Prefectural Environmental Pollution Research Center, 93 - 100.","Walker, F. (1848) List of the specimens of dipterous insects in the collection of the British Museum. Part 1. London, 352 pp.","Cranston, P. S. (1997) Revision of Australian Rheotanytarsus Thienemann & Bause (Diptera: Chironomidae), with emphasis on immature stages. Invertebrate Systematics, 11, 705 - 734. https: // doi. org / 10.1071 / IT 96025","Sasa, M. (1980) Studies on chironomid midges of the Tama River. Part 2. Description of 20 species of Chironominae recovered from a tributary. Research Report from The National Institute for Environmental Studies, 13, 1 - 107.","Wang, X. H. & Guo, Y. H. (2004) A review of the genus Rheotanytarsus Thienemann & Bause from China (Diptera: Chironomidae: Tanytarsini). Zootaxa, 650 (1), 1 - 19. https: // doi. org / 10.11646 / zootaxa. 650.1.1"]}

Rheotanytarsus vallenduuki Yao & Liu sp. n. (Figs 1D, 5A–E) Type material. Holotype: male (NKU: XL794), China, Guangdong, Guangzhou, Lanxi, 12. iv. 2018, light trap, leg. X.L. Lin. Etymology. Named after Prof. Henk Vallenduuk, for his outstanding contribution to the knowledge of Chironomidae; noun in nominative case. Diagnosis. The species can be distinguished from known species of Rheotanytarsus by the following combination of characters: antenna with 13 flagellomeres, AR 0.32; thorax with dark brown parallelogram-shaped spots and postnotum dark brown; anal tergite bands fused, arching upwards basally and horizontal in the middle; anal point with slightly swollen apex; digitus reduced and not visible; the stem of median volsella curved and covered with relatively short foliate setae and simple setae; median volsella with long, thin and foliate setae apically; inferior volsella curved and with equal-width; gonostylus gradually tapered and rounded apically. Description. Adult male (n = 1) Total length 1.57 mm. Wing length 1.05 mm. Total length/wing length 1.50. Wing length/length of profemur 1.99. Colouration (Fig. 1D). Thorax pale brown with dark brown parallelogram-shaped spots and postnotum dark brown; legs pale brown, femur and tibia of fore leg darker apically, femur of mid and hind legs darker apically; abdomen pale yellow. Head. Antenna with 13 flagellomeres, ultimate flagellomere 142 μm long. AR 0.32. Temporal setae 8. Clypeus with 18 setae. Tentorium 58 μm long, 11 μm wide. Palpomere lengths (in μm): 49, 40, 104, 146, 238; Pm5/ Pm3 2.29. Third palpomere with 2 sensilla clavata distally. Thorax. Dorsocentrals 7; acrostichals 10; prealar 1. Scutellum with 4 setae. Halteres with 7 setae. Wing (Fig. 5A). VR 1.59. Brachiolum with one seta, Sc bare, R with 16 setae, R 1 with 20 setae, R 4+5 with 41 setae, M 1+2 with 45 setae, M 3+4 with 30 setae, false vein with 81 setae, Cu with 13 setae, Cu 1 with 14 setae, PCu with 44 setae, An with 23 setae, remaining veins bare. Cell r 4+5 with c. 250 setae, m with 3 setae, m 1+2 with c. 200 setae, m 3+4 with c. 100 setae, cu+an with c. 130 setae. Legs. Fore leg bearing single tibial spur, broken. Combs of mid tibia 25 μm wide with 21 μm long spur, and 32 μm wide with 26 μm long spur; combs of hind tibia 33 μm wide with 24 μm long spur, 35 μm wide with 29 μm long spur. Tarsomeres of mid leg lost during DNA extraction. Lengths (in μm) and proportions of legs as in Table 4. Hypopygium (Figs. 5 B-E). Tergite IX 70 μm long, with two median setae at base of anal point; anal tergal bands fused, arching upwards basally and horizontal in middle. Anal point 8 μm long, relatively short and only reaching a little beyond tergite, with slightly swollen apex, bearing four lateral setae on each side; crests of V-type and fused apically, nearly reaching apex of anal point. Transverse sternapodeme 32 μm long, with obvious oral projections. Phallapodeme 43 μm long. Gonocoxite 73 μm long, basal microtrichia area right triangle. Gonostylus 60 μm long, gradually tapered and rounded apically. Superior volsella (Fig. 5D) 35 μm long, rectangular, with two anteromedian setae, four dorsal setae and one ventral seta. Digitus reduced and not visible. Median volsella (Fig. 5E) 90 μm long, well reaching beyond apex of inferior volsella, with about five long, thin and foliate setae apically; stem slightly curved, covered with simple setae and about two relative short foliate setae basally. Inferior volsella 59 μm long, markedly curved with equal width, with microtrichia. HR 1.22. HV 2.62. Female and immatures. Unknown. Remarks. The new species resembles Rheotanytarsus buculicaudus Kyerematen, 2000 by having similar shapes of anal tergite bands, median volsella and inferior volsella, but can be separated from the latter species by the following combination characters: superior volsella rectangular, inferior volsella with microtrichia, cell m with only three setae, and tibia of fore leg darker apically; whereas superior volsella oval-like, inferior volsella without microtrichia, cell m with 20 setae, and tibia of fore leg pale in R. buculicaudus.

Rheotanytarsus buculicaudus Kyerematen & Saether, 2000 Rheotanytarsus buculicaudus Kyerematen & Saether, 2000: 43; Kyerematen, Saether & Andersen, 2000: 165 Specimen examined. 5 males (BDN No. 20401, 20402, 20403, 20404, 20405), China, Fujian Province, Yongtai Country, 17. ix. 2002. Leg. Zh Liu. 1 male (BDN No 20020), China, Fujian Province, Jianning Country. 25. ix. 2002. Leg. Zh Liu Light trap. Diagnosis. This species can be separated from other members of the group by the following combination of characters: anal tergal bands nearly horizontal, and inferior volsella without microtrichia. Distribution. Ghana and China (Fujian).

Rheotanytarsus oss Cranston, 1997 (Figs 1C, 4A–E) Rheotanytarsus oss Cranston, 1997: 722; Kyerematen, Saether & Andersen, 2000: 163 Specimens examined: One male (NKU: MHMA02), China, Yunnan, Xishuangbanna, Menghai, Meng’ang, 6.v. 2013, sweep net, leg. X.L. Lin. Diagnosis. The species can be distinguished from known species of Rheotanytarsus by the following combination of characters: antenna with 13 flagellomeres; anal tergite bands of V-type and separated; anal point slightly constricted in the middle and swollen apically; superior volsella bulb-like, with one knob-like structure dorsally; the stem of median volsella curved, with five thin and long setae apically; inferior volsella curved and mostly with equal width. Description. Adult male (n = 1) Total length 1.69 mm. Wing length 0.95 mm. Total length/wing length 1.77. Wing length/length of profemur 1.84. Colouration (Fig. 1C). Thorax pale yellow, with pale brown stripes and postnotum brown, the femur and tibia of fore leg brown, mid and hind legs brown except the basal half of femur pale yellow. Head. Antenna with 13 flagellomeres, ultimate flagellomere 68 μm long. AR 0.16, relatively small. Temporal setae 7. Clypeus with 15 setae. Tentorium 81 μm long, 13 μm wide. Palpomere lengths (in μm): 26, 26, 54, 72, 136; Pm5/ Pm3 2.52. Third palpomere with 2 sensilla clavata distally. Thorax. Dorsocentrals 7; acrostichals 8; prealar 1. Scutellum with 4 setae. Wing (Fig. 4A). VR 1.56. Brachiolum with one seta, Sc bare, R with 11 setae, R 1 with 17 setae, R 4+5 with 35 setae, M 1+2 with 33 setae, M 3+4 with 20 setae, false vein with 84 setae, Cu with 11 setae, Cu 1 with 11 setae, PCu with 36 setae, An with 17 setae, remaining veins bare. Cell r 4+5 with c. 250 setae, m with two setae, m 1+2 with c. 150 setae, m 3+4 with c. 100 setae, cu+an with c. 120 setae. Legs. Fore leg bearing single tibial spur, 24 μm long. Combs of mid tibia 23 μm wide with 18 μm long spur, and 29 μm wide with 18 μm long spur; combs of hind tibia 31 μm wide with 23 μm long spur, 34 μm wide with 28 μm long spur. Tarsomere 1 of mid leg with four sensilla chaetica. Lengths (in μm) and proportions of legs as in Table 3. Hypopygium (Figs. 4B–E). Tergite IX 64 μm long, with five weak median setae at base of anal point; anal tergal bands of V-type, with a small tilt angle, and with a little bit of basal bands. Anal point 26 μm long, slightly constricted in middle and swollen apically with rounded apex, bearing seven lateral setae on each side; crests of V-type and opened, nearly reaching apex of anal point. Transverse sternapodeme 32 μm long, with oral projections. Phallapodeme 56 μm long. Gonocoxite 77 μm long. Gonostylus 74 μm long, gradually tapered, with rounded apex. Superior volsella (Fig. 4D) 31 μm long, bulb-like, with two anteromedian setae, three dorsal setae on a knob-like structure on the dorsal, and one ventral seta near base. Digitus reduced and not visible. Median volsella (Fig. 4E) 99 μm long, well reaching beyond apex of inferior volsella; stem curved, covered with simple setae, and with five long foliate setae apically. Inferior volsella 59 μm long, curved and mostly with equal width, with microtrichia. HR 1.04. HV 2.28. Remarks. Rheotanytarsus oss is recorded in China for the first time. The Chinese specimen fits well with the original description in Cranston (1997) and the review of the pellucidus species group (Kyerematen et al. 2000). Neither of the two studies described and figured the digitus, we found that reduced, and one ventral seta present in the Chinese specimen. Distribution. Australia, Thailand and China (Yunnan)., Published as part of Liu, Wen-Bin, Yao, Yuan, Chang, Tong, Yan, Chun-Cai & Lin, Xiao-Long, 2022, Contribution to the knowledge of Rheotanytarsus pellucidus species group from China (Diptera, Chironomidae): three new and one newly recorded species, pp. 145-156 in Zootaxa 5188 (2) on pages 151-152, DOI: 10.11646/zootaxa.5188.2.4, http://zenodo.org/record/7087541, {"references":["Cranston, P. S. (1997) Revision of Australian Rheotanytarsus Thienemann & Bause (Diptera: Chironomidae), with emphasis on immature stages. Invertebrate Systematics, 11, 705 - 734. https: // doi. org / 10.1071 / IT 96025","Kyerematen, R. A., Saether, O. A. & Andersen, T. (2000) A review of the Rheotanytarsus pellucidus group (Diptera: Chironomidae). In: Hoffrichter, O. (Ed.), Late 20 th century research on Chironomidae: an Anthology from 13 th International Symposium on Chironomidae, Shaker Verlag, Achen, pp, 147 - 181."]}

Rheotanytarsus apiculus Wang & Guo, 2004 Rheotanytarsus apiculus Wang & Guo, 2004: 11 Specimen examined. Holotype male (BDN No. 07458), China, Yunnan Province, Jinghong Country. 3. iv. 1987. Leg. H. Zou, sweep net. Diagnosis. This species can be separated from other members of the group by the following combination of characters: anal point long and narrow, anal crest reduced. Distribution. China (Yunnan)., Published as part of Liu, Wen-Bin, Yao, Yuan, Chang, Tong, Yan, Chun-Cai & Lin, Xiao-Long, 2022, Contribution to the knowledge of Rheotanytarsus pellucidus species group from China (Diptera, Chironomidae): three new and one newly recorded species, pp. 145-156 in Zootaxa 5188 (2) on page 154, DOI: 10.11646/zootaxa.5188.2.4, http://zenodo.org/record/7087541, {"references":["Wang, X. H. & Guo, Y. H. (2004) A review of the genus Rheotanytarsus Thienemann & Bause from China (Diptera: Chironomidae: Tanytarsini). Zootaxa, 650 (1), 1 - 19. https: // doi. org / 10.11646 / zootaxa. 650.1.1"]}

Rheotanytarsus ashei Yao & Liu sp. n. (Figs. 1A, 2A–E) Type material. Holotype: male (NKU: XJ59), China, Zhejiang, Xianju, Danzhuxiang, 24. v. 2016, light trap, leg: X. Qi. Paratypes: one male (NKU: CBL116) China, Guangdong, Shaoshan, Shixing, Chebaling National Nature Reserve, 1–11. xii. 2020, malaise trap, leg: L. R. Lu. One male (NKU: XJ184) China, Zhejiang, Taizhou, Xianju, Kuocangshan, Canglingkeng, 10–24. v. 2017, malaise trap, leg: X. Qi. One male (NKU: ZJ210) China, Zhejiang, Yueqing, Lingdi, Hushangyang, 7. iv. 2019, light trap. leg: X.L. Lin. Etymology. Named after Prof. Patrick Ashe, for his outstanding contribution to the knowledge of Chironomidae; noun in nominative case. Diagnosis. The specie can be distinguished from known species of Rheotanytarsus by the following combination of characters: antenna with 13 flagellomeres, and AR 0.26–0.33; thorax with dark brown parallelogram-shaped spots and postnotum dark brown; anal tergite bands separated and horizontal; superior volsella rectangular and broad; inferior volsella slightly curved and apically swollen; gonostylus with pointed apex. Description. Adult males (n = 4, unless stated). Total length 1.41–2.08, 1.75 (3) mm. Wing length 1.01–1.42, 1.19 (3) mm. Total length/wing length 1.40–1.47 (3). Wing length/length of profemur 2.05–2.24, 2.16. Colouration (Fig. 1A). Thorax pale brown with dark brown parallelogram-shaped spots and postnotum dark brown, legs pale brown with apical portion of femur darker, and abdomen pale yellow. Head. Antenna with 13 flagellomeres, ultimate flagellomere 116–172, 138 (3) μm long. AR 0.26–0.33, 0.29 (3). Temporal setae 6–8, 7. Clypeus with 14–20, 17 setae. Tentorium 72–78, 75 μm long, 7–14, 11 μm wide. Palpomere lengths of three specimens (in μm): 24–36, 28; 25–35, 28; 57–63, 60; 77–90, 84; 131–165, 145; Pm5/ Pm3 2.21–2.30, 2.42. Third palpomere with 2 sensilla clavata distally. Thorax. Dorsocentrals 7–8, 8; acrostichals 6–9, 8; prealars 1. Scutellum with 2–4, 4 setae. Halteres with 7–9, 8 (3) setae. Wing (Fig. 2A). VR 1.61–1.71, 1.66. Brachiolum with one seta, Sc bare, R with 14–17, 16 setae, R 1 with 18–27, 22 setae, R 4+5 with 39–56, 46 setae, M 1+2 with 37–46, 41 setae, M 3+4 with 20–30, 25 setae, false vein with 59–70, 63 setae, Cu with 12–16, 14 setae, Cu 1 with 15–20, 17 setae, PCu with 34–45, 40 setae, An with 19–24, 22 setae, remaining veins bare. Cell r 4+5 with c. 200 setae, m with 3–4, 4 setae, m 1+2 with c. 200 setae, m 3+4 with c. 100 setae, cu+an with c. 130 setae. Legs. Fore leg bearing single tibial spur, 21–23, 22 μm long. Combs of mid tibia 22–24, 23 μm wide with 15– 26, 22 μm long spur, and 23–36, 29 μm wide with 18–28, 23 μm long spur; combs of hind tibia 20–33, 26 μm wide with 15–30, 21 μm long spur, 29–34, 32 μm wide with 24–27, 25 μm long spur. Tarsomere 1 of mid leg of paratypes with 2–3, 3 (3) sensilla chaetica. Lengths (in μm) and proportions of legs as in Table 1. Hypopygium (Figs. 2 B-E). Tergite IX 86–88, 87 μm long, with 3–7, 5 median setae at base of anal point; anal tergal bands separated and horizontal. Anal point 22–29, 25 μm long, constricted in the middle and apically swollen, bearing 5–7, 6 lateral setae on each side; crests somewhat parallel and nearly reaching apex of anal point, basally developed. Transverse sternapodeme 34–41, 38 μm long, with oral projections. Phallapodeme 42–67, 55 μm long. Gonocoxite 78–94, 84 μm long. Gonostylus 61–80, 70 μm long, gradually tapered and pointed apically. Superior volsella (Fig. 2D) 35–43, 38 μm long, broad and somewhat obovoid, with 2–3, 3 anteromedian setae and three dorsal setae near apex. Digitus triangular, outer margin curved from middle, bearing one seta located on cylindrical tubercle near base. Median volsella (Fig. 2E) 100–114, 108 μm long, well reaching beyond the apex of inferior volsella, with about six long and thin foliate setae; stem covered with simple setae and slightly curved. Inferior volsella 51–52, 51 μm long, slightly curved and apically swollen, with microtrichia. HR 1.13–1.30, 1.20. HV 2.31–2.61, 2.48. Female and immatures. Unknown. Remarks. The new species resembles Rheotanytarsus buculicaudus Kyerematen, 2000 by having similar shapes of anal tergite bands, anal crest and median volsella, but can be separated from the latter species by the following combination characters: superior volsella somewhat obovoid, anal point constricted in the middle, inferior volsella with microtrichia, and gonostylus with pointed apex; whereas superior volsella rounded, anal point with parallel-sided apex, inferior volsella without microtrichia, and gonostylus with blunt apex in R. buculicaudus., Published as part of Liu, Wen-Bin, Yao, Yuan, Chang, Tong, Yan, Chun-Cai & Lin, Xiao-Long, 2022, Contribution to the knowledge of Rheotanytarsus pellucidus species group from China (Diptera, Chironomidae): three new and one newly recorded species, pp. 145-156 in Zootaxa 5188 (2) on pages 146-148, DOI: 10.11646/zootaxa.5188.2.4, http://zenodo.org/record/7087541