Pseudostegana husaensis, Gong & Chen, 2018

Gong, Lu & Chen, Hongwei, 2018, Seven new species of the genus Pseudostegana (Diptera: Drosophilidae) from South-west China, with DNA barcoding information, Journal of Natural History 52 (31 - 32), pp. 2097-2119 : 2112-2113

Pseudostegana husaensis sp. nov.

( Figures 4 (g–l) and 9)

Diagnosis

This species strongly resembles P. latifasciata Chen and Toda in Chen et al. (2005) from Yunnan, China in the slender palpus ( Figure 4 (g)) and wing pattern ( Figure 4 (i)), but can be distinguished from it by the male terminalia ( Figure 9); in this species, paramere apically slightly bifurcated; aedeagus expanded ventrad and dorsad on distal one-third in lateral view. The 10.1% interspecific genetic distance to P. latifasciata is the smallest within this group; there are four diagnostic sites between P. husaensis sp. nov. and P. latifasciata ( Figure 2).

Description

Male and female. Head ( Figure 4 (g,j)): Ocellar triangle brown, slightly narrowly elongated to anterior margin of frons. Frons brown. Pedicel and first flagellomere yellow. Face yellow above, brown below. Palpus brown and slender in both sexes. Clypeus dark brown. Gena brown. Thorax ( Figure 4 (h,k)): Scutum anteriorly brownish yellow and with thin medial stripe, posteriorly brown. Pleura nearly dark brown.

Katepisternal setae two. Scutellum nearly brown, pale at tip. Legs: Yellow, dark brown on tibiae mid and hind legs. Abdomen ( Figure 4 (l)): All tergites nearly black. Sternites yellow on second to fourth, brown to black on the rest. Male terminalia ( Figure 9): Epandrium slightly roundly protruding on ventral margin, with about 17 setae per side. Surstylus protruding on antero- and posteroventral corners. Cercus ventrally slightly protruding. Paramere subapically with one triangular process and two long sensilla, subdistally with numerous sensilla on dorsal projection. Basal process of aedeagus slender, with about six finger-like projections.

Measurements

BL = 2.67 mm in holotype (range in one male and one female paratypes: 2.73 in male, 2.80 in female), ThL = 1.10 mm (1.07 in male, 1.03 in female), WL = 2.20 mm (2.60 in male, 1.93 in female), WW = 1.07 mm (0.97 in male, 0.90 in female), arb = 6/1 (6/1), avd = 0.85 (0.82–1.00), adf = 1.86 (1.71–1.83), flw = 2.29 (1.43–2.00), FW/HW = 0.41 (0.39–0.41), ch/o = 0.06 (0.03– 0.06), prorb = 1.08 (1.00–1.15), rcorb = 0.20 (0.19), vb = 0.50 (0.80–1.00), dcl = 0.28 (0.27– 0.28), sct1 = 1.10 (1.04), sterno = 0.57 (0.65), orbito = 0.67 (0.86–1.00), dcp = 0.16 (0.14–0.16), sct1p = 1.10 (1.30–1.50), C = 2.06 (1.74–1.95), 4c = 1.80 (1.85–2.11), 4v = 3.50 (3.50–3.67), 5x = 1.08 (1.00–1.17), ac = 18.00 (18.50–19.00), M = 0.70 (0.65–0.78), C3F = 0.81 (0.80–0.81).

Type material

Holotype male ( SCAU, No. 111423), China: Husa, Longchuan , Yunnan, 24.461°N, 97.753°E, altitude 1200 m, 20 August 2016, ex tussock, H.W. Chen . Paratypes: one male, one female ( SCAU, Nos. 111424–25), same data as holotype .

Etymology

Toponym, according to the locality of type specimens.