Rhodesiella longiseta, Cai & Yang & Nartshuk & Liu, 2021

Cai, Xiaodong, Yang, Ding, Nartshuk, Emilia P. & Liu, Xiaoyan, 2021, Four new species of the genus Rhodesiella from Xizang Autonomous Region, China (Diptera: Chloropidae), Zootaxa 4970 (2), pp. 372-384 : 377-378

Rhodesiella longiseta sp. nov.

Figs 2 , 6 , 13–16

Diagnosis. Gena 0.25 times as deep as depth of first flagellomere. Antenna yellow except for scape reddish brown. Scutellum 1.26 times as long as wide, with 3 pairs of yellow scutellar setae on black tubercles, 2 times as long as wide. Epandrium light brown, bearing 1 pair of long setae on ventral margin of its opening. Surstylus nearly triangular in lateral view.

Description. Male ( Figs. 2 , 6 ). Body length without antennae 2.40–2.56mm, wing length 2.34–2.40mm.

Head black, much wider than long; length, width and height ratio as 1: 2.1: 1.25; frons reddish brown, 0.93 times as long as wide, width measured at level of anterior ocellus, projecting slightly in front of eye; face concave; gena brownish black, narrow, 0.25 times as deep as depth of first flagellomere; parafacial inconspicuous. Ocellar triangle polished black, smooth, reaching the anterior margin of frons with obtuse apex; ocellar tubercle reddish brown. Clypeus brownish black. Setae and setulae on head yellow. Antenna yellow except for scape reddish brown, first flagellomere 0.8 times as long as deep; arista slender, brownish black except for yellow basally, with short pubescence. Proboscis and palpus yellow with yellow setulae.

Thorax black, slightly narrower than head. Scutum convex, 0.9 times as long as wide. Scutellum elongate, subtriangular; 1.26 times as long as wide, 0.72 times as long as scutum, with 3 pairs of yellow scutellar setae on black tubercles, 2 times as long as wide. Ap sctl s 0.7 times as long as scutellum and 3 times as long as basal l sctl s; distal l sctl s 1.4 times as long as basal l sctl s. Distance between tips of tubercles of ap sctl s shorter than that between those of ap sctl s and distal l sctl s; distance between tips of tubercles of basal and distal l sctl s shorter than that between those of ap sctl s. Setae and setulae on thorax yellow; npl s 1+1. Legs light yellow, except tarsomeres 5 brown distally. Mid-tibia with a distinct, yellow apical spur. Hind femur not thickened, 1.6 times as broad as succeeding tibia at middle. Setulae on legs light yellow. Wing hyaline, 2.4 times as long as wide; veins yellowish brown, relative lengths of costal sections: 2nd: 3rd: 4th = 1.6: 1.3: 0.8; crossvein r-m slightly distad beyond middle of discal cell, at basal 0.57 of its length; R 4+5 and M 1+2 nearly parallel medially; ultimate section of M 1+2 very slightly concave forward basally. Halter yellowish white.

Abdomen brown with segments 1+2 membranous, yellow; tergite 3 light brown; venter yellow. Setulae yellow.

Male genitalia ( Figs. 13–16 ): Epandrium light brown with yellow setulae, wider than long in dorsal view and longer than high in lateral view, bearing 1 pair of long setae on ventral margin of its opening, with a widely produced posteroventral process. Surstylus dark brown to light brown, basally broad, distally narrowed, nearly triangular in lateral view. Hypandrium U-shaped. Pregonite longer than postgonite, postgonite incurved at basal 2/5. Distiphallus long, cylindrical, beyond lower margin of hypandrium in dorsal view, distally narrowed.

Female. Body length without antennae 2.90mm, wing length 2.64mm. External characteristics similar to male, except for hind tarsomere 5 yellowish brown; tergite 3 brown.

Type material. Holotype ♂, CHINA: Xizang: Yadong, Xiasima , 27°29’N, 88°54’E, 20. viii. 2013, 3020 m a.s.l., leg. Xiaoyan Liu ; Paratypes 2 ♂♂, same data as holotype ; 1 ♂, 2 ♀♀, Xizang: Motuo, Xironggou , 29°42’N, 95°35’E, 3. viii. 2019, 2786 m.a.s.l., leg. Qicheng Yang ; 1 ♂, Xizang: Milin, Nanyigou , 29°11’N, 94°12’E, 7. viii. 2018, 3061 m a.s.l., leg. Liang Wang.

Etymology. The specific name is from the Latin longus (“long”) and seta (“seta”), referring to 1 pair of long setae on ventral margin of epandrium.

Remarks. The new species is similar to R. chui KaNmIYa, 1987 from Taiwan in the following features: ocellar triangle polished black; scutellum with 3 pairs of yellow scutellar setae on black tubercles; hind femur not thickened and crossvein r-m distad beyond middle of discal cell. But it can be separated from R. chui by the following features: distance between tips of tubercles of basal and distal l sctl s shorter than that between those of ap sctl s; surstylus nearly triangular in lateral view. In R. chui , the distance between tips of the tubercles of basal and distal l sctl s is as long as that between those of ap sctl s; and the surstylus is nearly rectangular in lateral view ( Kanmiya, 1987).

Figures

FIGURES 1–4. Rhodesiella species, male habitus, lateral view. 1 R. arcuata sp. nov.; 2 R. longiseta sp. nov.; 3 R. perpendicularis sp. nov.; 4 R. uncata sp. nov. Scale bar = 0.5 mm.

FIGURES 5–8. Rhodesiella species, male habitus, dorsal view. 5 R. arcuata sp. nov.; 6 R. longiseta sp. nov.; 7 R. perpendicularis sp. nov.; 8 R. uncata sp. nov. Scale bar = 0.5 mm.

FIGURES 13–16. Rhodesiella longiseta sp. nov. male. 13 epandrium, posterior view; 14 epandrium, lateral view; 15 hypandrium and phallic complex, ventral view; 16 Scutellum, dorsal view. Scale bar = 0.1 mm.