Dicraeus crassispinus, Liu & Yang & Nartshuk, 2019

Liu, Xiaoyan, Yang, Ding & Nartshuk, Emilia P., 2019, New species and records of Dicraeus Loew, 1873 from China (Diptera: Chloropidae), Zootaxa 4554 (2), pp. 351-370 : 354

Dicraeus crassispinus sp. nov.

Figs 1 , 12–15

Diagnosis. Gena 0.5 times as wide as first flagellomere. Ocellar triangle reaching anterior margin of frons. Scutum brown with 5 longitudinal black stripes. Scutellum blackish brown. Legs yellow with tarsomeres 5 brown. Surstylus distinctly shorter than epandrium in lateral view, basal 2/3 nearly parallel-sided, recurved posteriorly, some thickened setae on middle surface.

Description. Male ( Fig. 1 ). Body length 3.5 mm, wing length 1.8 mm.

Head yellow, as wide as thorax, 0.85 times as long as high in profile, face somewhat concave in lateral view, facial carina indistinct; frons yellowish brown with anterior 1/2 yellow, as long as wide, projecting slightly in front of eye; gena broad, about 0.5 times as wide as first flagellomere, with few brown setulae on ventral margin; parafacial indistinct; clypeus light yellow; vibrissal angle obtuse. Ocellar triangle yellowish brown with distal 1/4 yellow, smooth, shiny, reaching anterior margin of frons, with pointed apex; ocellar tubercle brown. Occiput black. Cephalic setae and setulae black. Antenna yellow with thick grey pruinescence except for dorsal 1/2 of first flagellomere yellowish brown; first flagellomere 0.8 times as long as wide; arista brown with short brown pubescence. Proboscis brown with brown setulae; palpus yellow with black setulae.

Scutum 1.1 times as long as wide, brown with 5 longitudinal black stripes, medial stripe slightly broad and extending to posterior 4/5 of scutum, basal 1/3 of inner lateral stripes narrow, outer lateral stripes short and narrow. Postpronotal lobe yellow with a reddish yellow spot. Thoracic pleuron shiny yellow except for anteroventral portion of anepisternum brown; anterior 1/2 of anepumeron, ventral 1/2 of katepisternum and posteroventral portion of meron yellowish brown. Scutellum blackish brown, 0.5 times as long as wide; apical scutellar seta 1.5 times as long as scutellum; subapical scutellar seta as long as scutellum. Postscutellum black. Setae and setulae on thorax black; notopleurals 1+2, anterior notopleural seta as long as posterior notopleural seta; anterior postalar seta as long as posterior postalar seta; 1 pair of dorsocentral setae developed, 1.8 times as long as anterior postalar setae. Legs slender, yellow with tarsomeres 5 brown. Mid tibia with a short black subapical spur, which is longer than diameter of tibia. Tibial organ long and narrow. Setulae on legs black. Wing 2.6 times as long as wide, hyaline; veins brown. Relative lengths of 2nd: 3rd: 4th costal sections = 8: 1.2: 1; r-m at basal 0.45 of discal medial cell. Halter pale yellow.

Abdomen brown except for tergite 1, distal portions of tergites 2–5 and tergites 7+8 yellow; venter yellow. Setulae brown.

Male genitalia ( Figs. 12–15 ): Epandrium yellow with brown distally, with long brown setulae, height 1.7 times width in lateral view; surstylus distinctly shorter than depth of epandrium in lateral view, basal 2/3 nearly parallelsided, recurved posteriorly; some thickened setae on middle surface. Cercus absent. Pre- and postgonites short, postgonite round distally, with few sensilla; basiphallus longer than wide, cylindrical; distiphallus short, membranous; phallapodeme sclerotized, long, with basal stalk broad in lateral view. Hypandrium closed, apically forming an arch.

Female. Unknown.

Type material. HOLOTYPE 6, CHINA, Yunnan, Honghe, Hekou, Binlangzhai Reservoir , 21. V. 2006, Xiushuai Yang Leg. (CAU) (photo and abdomen dissected). PARATYPES 2 66, same data as holotype ( CAU). All type specimens were stored in 75% ethanol .

Distribution. China (Yunnan).

Remarks. The new species is somewhat similar to D. ischaemi Kanmiya, 1971 , but can be separated from the latter by the following features: ocellar triangle reaching anterior margin of frons; first flagellomere round dorsodistally; surstylus distinctly shorter than depth of epandrium in lateral view, basal 2/3 nearly parallel-sided, recurved posteriorly; some thickened setae on middle surface; cercus absent. In D. ischaemi , the ocellar triangle is extended to a little beyond middle of frons; the first flagellomere has a dorsodistal angle; the surstylus is slender, slightly concave at middle, broadly round apically, and has 5 long thick setae; and the cercus is slender, finger-like ( Kanmiya 1971).

Etymology. The specific name is from the Latin crassispinus (“crassispina”), referring to the thickened setulae on inner side of surstylus.

Figures

FIGURES 1–5. Dicraeus species, habitus. 1 D. crassispinus sp. nov.; 2 D. curvus sp. nov.; 3 D. dentatus sp. nov.; 4 D. liupanshanensis sp. nov.; 5 D. minutidentatus sp. nov. Scale bar = 1 mm.

FIGURES 12–15. Dicraeus crassispinus sp. nov. male. 12 epandrium, posterior view; 13 epandrium, lateral view; 14 hypandrium and phallic complex, ventral view; 15 hypandrium and phallic complex, lateral view. Abbreviations: bas, basiphallus; dis, distiphallus; ep, epandrium; hyp, hypandrium; phal, phallapodeme; pog, postgonite; prg, pregonite; sur, surstylus. Scale bar = 0.1 mm.