Pseudostegana latiapicula, 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 : 2102-2107

Pseudostegana latiapicula sp. nov.

( Figures 3 (a–f), and 6)

Diagnosis

This species is most closely related to P. angustifasciata Chen and Wang in Chen et al. (2005) from Yunnan, China, in the wing pattern ( Figure 3 (c)), but can be distinguished from it by the paramere and aedeagus; in this species, paramere subapically triangularly expanded in ventral view, apically bifurcated: once acute process, the other lobe shaped ( Figure 6 (b,c)); aedeagus distally roundly expanded in lateral view ( Figure 6 (c)). The interspecific genetic distance to P. angustifasciata is 13.0%, but to P. bilobata Li et al. (2010) 12.2% is the smallest within this group; there are 10 diagnostic sites between P. latiapicula sp. nov. and P. angustifasciata , and eight diagnostic sites between P. latiapicula sp. nov. and P. bilobata ( Figure 2).

Description

Male. Head ( Figure 3 (a,d)): Ocellar triangle brown, narrowly elongated to anterior margin of frons. Frons brown. Pedicel yellow; first flagellomere greyish yellow. Face yellow. Clypeus brown. Palpus yellow and slender. Gena brownish. Thorax ( Figure 3 (b,e)): Scutum medially pale yellow, laterally brownish. Pleura brown. Katepisternal setae two. Scutellum mostly brownish, yellow at tip. Legs: Yellow. Abdomen ( Figure 3 (f)): First to third tergites glossy, yellow, brown to black along posterior margins; the rest brown to dark brown except for yellow medially. Sternites yellow on second, brown on the rest. Male terminalia ( Figure 6): Epandrium broadened mid-posteriorly, roundly protruding on ventral margin, with about 17 setae per side. Surstylus ventrally slightly concave. Cercus dorsally elongated. Paramere subapically with two long sensilla, submedially with five small sensilla and one small projection in lateral view. Aedeagus strong in ventral view, basally slender in lateral view, with slender, slightly sclerotized basal processes.

Measurements

BL (body length) = 3.07 mm, ThL (thorax length) = 1.07 mm, WL (wing length) = 2.63 mm, WW (maximum wing width) = 1.37 mm, arb (dorsal branches/ventral branches of arista) = 6/1, avd (longest ventral branch/longest dorsal branch of arista in length) = 0.46, adf (longest ventral branch/longest dorsal branch of arista in length) = 2.17, flw (length/ width of first flagellomere) = 2.67, FW/HW (frontal width/head width) = 0.46, ch/o (maximum width of gena/maximum diameter of eye) = 0.05, prorb (proclinate orbital/posterior reclinate orbital in length) = 0.93, rcorb (anterior reclinate orbital/posterior reclinate orbital in length) = 0.18, vb (subvibrissal/vibrissa in length) = 0.25, dcl (anterior dorsocentral/ posterior dorsocentral in length) = damaged, sct1 (basal scutellar/apical scutellar in length) = damaged, sterno(anterior katepisternal/posterior katepisternal in length) = 0.52, orbito (distance between proclinate and posterior reclinate orbitals/distance between inner vertical and posterior reclinate orbital) = 0.78, dcp (length distance between ipsilateral dorsocentrals/cross distance between anterior) = 0.19, sct1p (distance between ipsilateral scutellars/cross distance between apical scutellars) = 1.33, C second costal section between subcostal break and R2+3/third costal section between R2+3 and R4 +5) = 1.85, 4c (third costal section between R2+3 and R4+5/M1 between r-m and dmcu) = 1.69, 4v (M1 between dm-cu and wing margin/M1 between r-m and dm-cu) = 2.94, 5x (CuA1 between dm-cu and wing margin/dm-cu between M1 and CuA1) = 1.50, ac (CuA1 between dm-cu and wing margin/dm-cu between M1 and CuA1) = 9.00, M (CuA1 between dm-cu and wing margin/M1 between r-m and dm-cu) = 0.75, C3F (length of heavy setation in third costal section/length of heavy setation in third costal section + length of light setation in third costal section) = 0.75.

Type material

Holotype male ( SCAU, No. 111412), China: Mengdong, Cangyuan , Yunnan, 23.169°N, 99.231°E, altitude 1320 m, 6 May 2016, ex tussock, L. Zhu.

Etymology

A combination of the Latin words latus and apiculus, referring to the aedeagus being broadened distally.

Distribution

China (Yunnan).