Thienemanniella triangula, Fu, Yue, Saether, Ole & Wang, Xinhua, 2010

Fu, Yue, Saether, Ole & Wang, Xinhua, 2010, Thienemanniella Kieffer from East Asia, with a systematic review of the genus (Diptera: Chironomidae: Orthocladiinae), Zootaxa 2431, pp. 1-42 : 24-26

Thienemanniella triangula sp. n.

( Figs 17 A–C)

Type material. Holotype male (BDN No. 12204), CHINA: Sichuan Province, Ganzi State, Yajiang County (31°38΄N, 99° 58΄E), 2000 m a.s.l., light trap, 14.vi.1996, Xinhua Wang. Paratypes: CHINA: 6 males (BDN No. 13644, 12634, 12656, 13018, 13091, 13688), as holotype; Yunnan Province, Eryuan County, Niujie Town, Meici River (26°6'N, 99°56'E), 2332 m a.s.l., light trap, 1 male (BDN No. 09790), 2.VI.1996, Beixin Wang; Sichuan Province, Xiangcheng County, Shuoqu River (28° 56’ N, 99° 47’ E), 2700 m a.s.l., light trap, 2 males (BDN No. 13420, 13421), 12.vi.1996, Xinhua Wang.

Diagnostic characters. The species differs from other East Asian members of the genus by having antenna with 11 flagellomeres, having an AR 0.36–0.41, 0.39; triangular inferior volsella; phallapodeme with basal projection, joint with sternapodeme placed pre-lateral.

Etymology. Named by the species having triangular inferior volsella.

Description. Male imago (n = 9–10).

Total length 1.43–1.68, 1.57 mm. Wing length 0.86–1.15, 1.01mm. Total length / wing length 1.43–1.66, 1.55. Wing length / length of profemur 2.9–3.3, 3.1.

Coloration. Head brown to black. Antenna and palpomere pale brown. Thorax brown to dark brown. Abdominal segments brown. Legs yellowish brown. Wings almost hyaline, with pale yellow clava.

Head. Eyes hairy, reniform. Antenna with 11 flagellomeres; ultimate flagellomere 135–170, 150 µm long, with apical sensilla chaetica which extends a little way back from tip, antenna subapically expanded, with maximum width 37 µm; AR: 0.36–0.41, 0.39. Clypeus with 6–10, 8 setae. Tentorium 135–162, 142µm long. Stipes: 80–90, 85 µm long. Palpomeres length (in µm): 12–17, 15; 18–28, 22; 35–45, 41; 53–65, 58; 138–150, 145. Palpomere segment 2 ellipsoid, segment 3 and 4 rectangular, segment 5 long and slender; palpomere 5/ 3: 3.1–3.9, 3.7.

Thorax. Dorsocentrals 7–11, 9, prealars 3. Scutellum with 2 setae.

Wing ( Fig. 17 A). VR 1.6–1.8, 1.7. C length 330–380, 359 µm, C/wing length 0.34–0.38, 0.37. Cu length 460–500, 480 µm. Cu/wing length 0.46–0.50, 0.48. Wing width/wing length 0.40–0.45, 0.43. C with 14–17, 15 setae.

Legs. Spur of fore tibia 18–30, 25 µm long, spurs of mid tibia 13–20, 17 µm and 13–18,13 µm long, of hind tibia 23–33, 25 µm and 15–23 µm long. Width at apex of fore tibia 23–30, 25 µm, of mid tibia 23–33, 26 µm, of hind tibia 32–35, 33 µm. Tip of hind tibia comb composed of 9–12, 11 setae. Lengths and proportions of legs as in Table 4.

Hypopygium ( Fig 17 . B–C). Laterosternite IX with 1–2 long setae. Posterior margin straight, and with many short setae. Gonocoxite 80–115, 96 µm long with 4 setae apically. Gonostylus 45–53, 49 µm long with megaseta 5–8, 6 µm long. Superior volsella anteriomedially fused. Inferior volsella triangular with rounded margin. Transverse sternapodeme narrow, 35–43, 40(9) µm long, with oral projections; coxapodeme 30–38, 35 µm long; phallapodeme slightly curved, 48–58, 51(9) µm long, with projection basally. HR 1.5–2.2, 1.9, HV 3.0–3.3, 3.2.

Female and immature stages. Unknown.

Distribution. China (Sichuan and Yunnan Provinces).

Figures

FIGURES 17. Thienemanniella triangula sp. n., male. A. Wing; B. Hypopygium, dorsal view; C. Hypopygium, ventral view.