Thienemanniella sichuana, 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 : 20-22

Thienemanniella sichuana sp. n.

( Figs 14 A–C)

Type material. Holotype male (BDN No. 12225), CHINA: Sichuan Province, Daocheng County, Daocheng River (29°11΄ N, 100°06΄ E), 3700 m a.s.l., sweeping, 11.vi.1996, Xinhua Wang. Paratypes: CHINA: 2 males (BDN No. 11691, 11692), as holotype; Sichuan Province, Litang County, Shiliang River (30°2΄ N, 100°17΄ E), 3750 m a.s.l., light trap, 1 male (BDN No. 11664), 13.vi.1996, Xinhua Wang; Sichuan Province, Daocheng County, Sangdui Town (29°11΄ N, 100°06΄ E), 3700 m a.s.l., light trap, 6 males (BDN No. 11638, 11644, 13463, 11580, 11581, 11582), 10.vi.1996, Xinhua Wang.

Diagnostic characters. The species differs from other East Asian members of the genus by having an antenna with 12 flagellomeres; AR: 0.25–0.54, 0.45. Gonostylus stout and slightly hooked; inferior volsella triangular and posteriorly hooked; superior volsella separated from inferior volsella.

Etymology. The specific name refers to the Sichuan Province of China, where from the type material was collected.

Description. Male imago (n = 10).

Total length 1.68–2.12, 1.88 mm. Wing length 1.28–1.40, 1.01 mm. Total length / wing length 1.32–1.50, 1.40. Wing length / length of profemur 3.3–3.6, 3.4.

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

Head. Eyes hairy, reniform. Antenna with 12 flagellomeres; ultimate flagellomere 120–250, 204 µm long, with apical sensilla chaetica which extends a little way back from tip, antenna subapically expanded, with maximum width 28 µm; AR: 0.25–0.54, 0.45. Clypeus with 9–16, 13 setae. Tentorium 130–165, 144 µm long. Stipes: 55–65, 60 µm long. Palpomeres length (in µm): 18–23, 20; 20–30, 24; 45–60, 52; 58–73, 64; 98–118, 105. Palpomere segment 2 ellipsoid, segment 3 and 4 rectangular, segment 5 long and slender; palpomere 5/ 3: 1.7–2.2, 2.0.

Thorax. Dorsocentrals 6–10, 8, prealars 2. Scutellum with 1–2, 1 seta.

Wing ( Fig. 14 A). VR 1.6–1.8, 1.7. C length 470–540, 508µm, C/ wing length 0.37–0.39, 0.38. Cu length 610–680, 647 µm. Cu/ wing length 0.45–0.50, 0.48. Wing width/ wing length 0.35–0.38, 0.36. C with 15 setae in all specimens.

Legs. Spur of fore tibia 20–25, 23 µm long, spurs of mid tibia 10–15, 13 µm and 10–18, 15 µm long, and of hind tibia 20–33, 27 µm and 13–18, 15 µm long. Width at apex of fore tibia 20–38, 30 µm, of mid tibia 25– 35, 31 µm, and of hind tibia 30–38, 35 µm. Hind tibial comb composed of 9–14, 11 setae. Lengths and proportions of legs as in Table 3.

Hypopygium ( Figs 14 B–C). Posterior margin straight, and with many short setae, laterosternite IX with 2 long setae each side. Gonocoxite 103–145, 126 µm long with 2 apical seta. Gonostylus stout and slightly hooked, 35–53, 43 µm long with megaseta 5–8, 6 µm long. Superior volsella joined medially. Inferior volsella triangular. Transverse sternapodeme narrow, 30–50, 40 µm long with weak oral projections; coxapodeme 30– 38, 34 µm long; phallapodeme strongly curved, 38–58, 50 µm long. HR 2.3–3.8, 3.0, HV 3.7–5.3, 4.5. Female and immature stages. Unknown.

Distribution. China (Sichuan Province).

Figures

FIGURES 14. Thienemanniella sichuana sp. n., male. A. Wing; B. Hypopygium, dorsal view; C. Hypopygium, ventral view.