Tanytarsus dawai Lin, 2025

Zhang, Zhi-Chao, Rong, Yue-Xiao, Nyima, Tenzin, Zhang, Rui-Lei & Lin, Xiao-Long, 2025, Tanytarsus dawai sp. nov. and larval morphology of T. sinuatus within the T. norvegicus species group (Diptera: Chironomidae), Zootaxa 5633 (2), pp. 316-335 : 317-322

publication ID	https://doi.org/10.11646/zootaxa.5633.2.5
publication LSID	lsid:zoobank.org:pub:A04F0C32-C471-41BC-9DA3-8697981B374A
DOI	https://doi.org/10.5281/zenodo.15435273
persistent identifier	https://treatment.plazi.org/id/815C87EA-FFF1-596D-FF1A-0B4FE860F84E
treatment provided by	Plazi
scientific name	Tanytarsus dawai Lin
status	sp. nov.

Treatment

Tanytarsus dawai Lin , sp. nov.

urn:lsid:zoobank.org:act:031BCB5A-D91A-4C28-B79F-06BB3D4FA5FE

( Figs 2–10 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 )

Type material. Holotype: male ( SHOU & BOLD sample ID: XL157), China, Xizang, Xigaze City, Nilun Village , 29.31684°N, 88.93410°E, 3798 m a.s.l., sweep net, 22.VII.2014, leg. X.L. Lin. GoogleMaps Paratypes: female ( SHOU & BOLD sample ID: XL50), China, Xizang, Chamdo City, Ranwu Town, Ranwu Lake , 29.50581°N, 96.76048°E, 3963 m a.s.1., sweep net, 10.VII.2014, leg. X.L. Lin; 2 males ( SHOU & BOLD sample ID: XL117, XL118) GoogleMaps , China, Xizang, Shannan City, Gongga County, Gangdui Town , 29.27888°N, 90.82323°E, 3586 m a.s.1., sweep net, 18.VII.2014, leg. X.L. Lin; 4 males ( SHOU: XL8 , XL10 , XL11 ; SHOU & BOLD sample ID: XL9) GoogleMaps , China, Xizang, Shannan City, Yamzho Yumco , 29.18879°N, 90.56003°E, 4458 m a.s.l., sweep net, 18.VII.2014, leg. X.L. Lin; 5 males ( SHOU & BOLD sample ID: XL48; SHOU: XL49 , XL51 , XL52 , XL53 ) GoogleMaps , China, Xizang, Chamdo City, Ranwu Town, Ranwu Lake , 29.50581°N, 96.76048°E, 3963 m a.s.l., sweep net, 10.VII.2014, leg. X.L. Lin; 6 larvae ( SHOU & BOLD sample ID: XL431, XL432, XL434, XL435, XL437, XL440) GoogleMaps , China, Xizang, Chamdo City, Ranwu Town, Ruanwu Lake , 29.50581°N, 96.76048°E, 3963 m a.s.l., 10.VII.2014, leg. X.L. Lin. GoogleMaps

Etymology. The specific epithet is dedicated to Associate Professor Dawa from the Tibet Plateau Institute of Biology in Lhasa, Xizang, China, for his outstanding contribution to the knowledge of insects in Xizang; noun in genitive case.

Diagnostic characters. The adult male of the new species can be distinguished from known species of the Tanytarsus norvegicus species group by the following combination of characters: Tergite I-V with horizontal dark brown bands at the posterior quarter. AR 0.86–1.10. Ac absent. LR 1 1.55–1.71. Tarsomere l of mid leg with sensilla chaetica distally. Anal point slender triangular, with six lateral setae on each side, 8–11 spinulae evenly placed at 2/3 length of anal point. Superior volsella sub-rectangular with ventral, small patch of microtrichia. Digitus bent downwards. Stem of median volsella long, with six setiform lamellae and one distal, spatulate lamella. The larva of the new species can be distinguished from known species of the T. norvegicus species group by the following combination of characters: AHR 0.15–0.21. LOR 1.92–2.63. Mandible with one ventral apical tooth, three ventral inner teeth, four dorsal teeth. Mentum with 11 teeth; median tooth with small lateral notches. Premandible with five teeth in addition to lateral spine; premandibular brush well-developed.

Description. Adult male (n = 13).

Total length 3.68–4.08, 3.84 mm; wing length 2.25–2.93, 2.46 mm; total length/wing length 1.39–1.66, 1.56.

Colouration ( Figs 2B View FIGURE 2 ; 3A–B View FIGURE 3 ). Head and legs brown. Thorax and abdomen with pale brown ground colour. Ventral part of parapsidal suture, postnotum, preepisternum and median anepisternum II dark brown, scutum and epimeron II light brown. Tergite I–V with horizontal dark brown bands at the posterior quarter. Tergite VI with horizontal light brown band at the posterior seventh.

Head ( Fig. 3A View FIGURE 3 ). AR 0.86–1.10, 0.94. Antenna with 13 flagellomeres, ultimate flagellomere 500–619, 564 μm long. Frontal tubercles 25–38, 31 μm long, 8–13, 10 μm wide at base. Temporal setae 8–12, 10. Clypeus with 10–15, 13 setae. Tentorium 145–176, 156 μm long, 33–50, 39 μm wide. Palpomere lengths (μm): 35–40, 39; 38–63, 51; 102–140, 122; 118–145, 129; 200–237, 218.

Thorax ( Fig. 3B View FIGURE 3 ). Ac absent; Dc 7–10, 8; Pa 1; Scts 5–8, 6. Haltere with 4–5, 4 setae.

Wing ( Fig. 3C View FIGURE 3 ). VR 1.08–1.18, 1.11. Brachiolum with l seta, R with 8–21, 15 setae, R 1 with 6–15, 10 setae, R 4+5 with 7–28, 16 setae, M 1+2 with 3–57, 28 setae, M 3+4 with 1–11, 5 setae, false vein with 0–3 setae (usually 0), Cu with 0–6, 1 seta, Cu 1 with 0–3, 1 seta, r 4+5 with 79–115, 96 setae, m 1+2 with 14–117, 60 setae, m 3+4 with 0–17, 3 setae, remaining veins and cells bare.

Legs. Fore leg bearing single tibial spur 26–43, 34 μm long. Combs of mid tibia 11–21, 16 μm wide with 25–33, 30 μm long spur, and 10–20, 15 μm wide with 23–30, 27 μm long spur; combs of hind tibia 15–28, 22 μm wide with 28–38, 33 μm long spur, 17–27, 22 μm wide with 23–35, 31 μm long spur. Tarsomere l of mid leg with 4–7, 5 sensilla chaetica distally. Lengths and proportions of legs as in Table 1.

Hypopygium ( Figs 4–5 View FIGURE 4 View FIGURE 5 ). Tergite IX 100–125, 113 μm long. Anal tergite bands V-shaped, well separated, ending at mid-length of tergite. Anal point ( Fig. 5 View FIGURE 5 ) 48–67, 56 μm long, slender triangular, tapering near the apex, with six lateral setae on each side, 8–11, 9 spinulae evenly placed at 2/3 length of anal point. Transverse sternapodeme 62–91, 78 μm long, with oral projections. Phallapodeme 90–125, 101 μm long. Gonocoxite 152–177, 165 μm long. Gonostylus 140–173, 159 μm long. Superior volsella ( Fig. 4D View FIGURE 4 ) sub-rectangular, with concave inner margin, bearing seven dorsal setae and two ventral setae, ventral surface with small patch of microtrichia at posterior margin. Digitus long and bent downwards, curved, with swollen blunt apex, extending beyond the inner margin of superior volsella. Stem of median volsella 20–25, 23 μm long, with 6 setiform lamellae and one distal spatulate lamella ( Fig. 4E View FIGURE 4 ). Inferior volsella weakly curved, 100–128, 111 μm long, with 11–23, 19 strong setae. HR 0.94–1.18, 1.04; HV 2.36–2.66, 2.51.