Stegana, Meigen, 1830

Li, Tong, Cao, Huazhi, Gao, Jianjun & Chen, Hongwei, 2010, A revision of the subgenus Stegana (s. s.) (Diptera, Drosophilidae) from mainland China, Zoological Journal of the Linnean Society 158 (4), pp. 726-739 : 733-734

STEGANA ( STEGANA ) QUADRATA CAO & CHEN SP. NOV. ( FIGS 29–35)

Specimens examined: Holotype male, China: Yunnan, Xishuangbanna, Mengla, Bubang , Wangtianshu , 600 m, 21–24.iv.2007, ex tussock, JJ Gao ( SCAU, no. 120084) . Paratypes: one male and two females, same data and place as holotype, HW Chen & JJ Gao ( SCAU, no. 120285-87). Two males and one female, Yunnan, Xishuangbannan, Menglun , 580 m, 16–19.iv.2007, ex tussock, HW Chen & JJ Gao ( SCAU, no. 120288-90) .

Etymology: From the Latin word quadratus, referring to the aedeagus being slightly flattened apically.

Diagnosis: Mesonotum yellow, with four black stripes submedially and laterally, submedial pair divergent on posterior third; aedeagal peristome narrow, emarginate in ventral view ( Fig. 32).

Description: Male and female: frons yellow, with triangular brown patch below ocellar triangle. First flagellomere yellow, with black pubescence along margin. Face yellow, brownish on lower margin. Clypeus yellow. Katepisternum white, with brown stripe on upper part. Scutellum black, pale yellow along margin. Legs yellow except all femora black distally. Fore femur with five setae on distal part of ventral surface. Abdominal tergites I–VI black, with yellow patches laterally. Sternites dark brown to black. Male terminalia: surstylus with one strong prensiseta on outer surface ( Fig. 30). Hypandrium somewhat sclerotized anteromedially ( Fig. 31). Gonopods with one curved process posteromedially and two triangular processes submedially ( Figs 31, 33). Paramere with two long setae apically and some pubescence on inner margin ( Figs 32, 33). Aedeagus with numerous tentacle-like setae along peristome and spine-like processes ventrally, lacking pubescence ( Figs 32, 33).

Measurements: BL = 2.88 mm in holotype (range two male and four female paratypes: 3.12–3.40 mm in males, 3.32–3.80 mm in females), ThL = 1.63 mm (1.60–1.85 mm in males, 1.83–1.95 mm in females), WL = 2.32 mm (2.56–2.84 mm in males, 2.88– 3.16 mm in females), WW = 1.33 mm (1.38–1.50 mm in males, 1.48–1.63 mm in females). Indices: arb = 9/6 (10/7–11/6), avd = 0.68 (0.72–0.77), adf = 1.91 (1.80– 2.12), flw = 2.17 (2.20–2.40), FW/HW = 0.35 (0.36– 0.39), ch/o = 0.10 (0.09–0.12), prorb = 1.08 (1.09–1.33), rcorb = 0.80 (0.60–0.79), vb = 0.39 (0.32–0.47), dcl = 0.50 (0.41–0.53), presctl = 0.65 (0.69–0.81), sctl = 1.73 (1.66–1.94), sterno = 0.81 (0.82–0.90), orbito = 2.38 (2.05–2.56), dcp = 0.17 (0.16–0.23), sctlp = 1.24 (1.25–1.75), C = 1.95 (2.03–2.20), 4c = 1.32 (1.18–1.38), 4v = 2.15 (1.95–2.24), 5x = 1.08 (0.98– 1.15), ac = 7.17 (7.14–9.00), M = 0.60 (0.48–0.59), C3F = 0.73 (0.73–0.76).

Distribution: China (Yunnan).