Heleodromia (Heleodromia) didyma, Liu, Xiaoyan, Wang, Jinjing & Yang, Ding, 2012

Liu, Xiaoyan, Wang, Jinjing & Yang, Ding, 2012, Heleodromia Haliday newly recorded from China with descriptions of two new species (Diptera: Empidoidea), Zootaxa 3159, pp. 59-64 : 60

Heleodromia (Heleodromia) didyma sp. nov.

( Figs. 1–2 )

Diagnosis. Tergite 8 with 2 short processes at posterior margin. Epandrial lobe long, thin, finger-like; surstylus rather thick with acute tip. Fore femur with long av (slightly longer than femur thickness).

Description. Male. Body length 2.6–2.8 mm, wing length 3.2–3.3 mm. Head black with pale gray pollen. Eyes very narrowly separated on face, brownish. Setae and setulae on head black except posteroventral surface with pale setulae; ocellar tubercle distinct with pair of long oc. Antenna black; first flagellomere long conical, 1.6–1.7X longer than wide; arista very long, 2.0–2.1X length of first flagellomere; arista very short micropubescent. Proboscis long, 0.7–0.75X as long as head height, blackish to black with pale setulae. Palpus black with pale setulae (2–3 apical setulae long).

Thorax black with pale grey pollen. Setae and setulae on thorax black; pronotum with 1 seta laterally; 1 h, 1 npl, 2–3 short acr, 4 dc, 1 psa; scutellum with 2 setae. Legs black except tips of all femora dark brownish yellow. Setulae and setae on legs black except those on coxae pale; fore femur basally with row of 5 pale av setae (longest setae slightly longer than femur thickness), mid and hind femora with short pale av setulae. Fore femur 1.1X as thick as mid femur, mid and hind femora subequal in thickness. Wing hyaline, slightly tinged grayish; veins dark brown. Squama dark yellow, bordered with pale setulae. Halter dark yellow.

Abdomen black with pale gray pollen. Setulae and setae on abdomen pale. Male genitalia ( Figs. 1–2 ): tergite 8 and sternite 8 rather small; tergite 8 narrowed posteriorly, with pair of short processes at posterior margin. Epandrium and hypandrium much elongated and rather large; epandrium shorter than hypandrium in lateral view; epandrial lobe long, thin, finger-like; surstylus rather thick with acute tip.

Female. Body length 3.2 mm, wing length 3.2 mm. Similar to male, but palpus with strong blackish setae, all femora with short pale av.

Type material. HOLOTYPE 3, CHINA, Neimenggu, Helanshan, Shuimogou, Hougou, 38°59ʹN 105°51ʹE, 2010. VIII.4, Lihua Wang. PARATYPES: 1 3 1 Ƥ, same data as holotype.

Distribution. China (Neimenggu).

Etymology. The specific name refers to two marginal processes on tergite 8.

Remarks. This new species is somewhat similar to Heleodromia (Heleodromia) boreoalpina Saigusa from Japan, but can be easily separated from it by the tips of all femora being dark brownish yellow, the fore femur basally with one row of 5 long pale av setae (longest setae slightly longer than femur thickness), and the surstylus with the acutely pointed tip. In Heleodromia (Heleodromia) boreoalpina , the legs are entirely blackish, the femora lack prominent av setulae, and the surstylus is somewhat obtuse at tip ( Saigusa 1963).

Figures

FIGURES 1 – 2. Heleodromia (Heleodromia) didyma sp. nov. (male). 1. Tergite 8, dorsal view. 2. Genitalia, lateral view. Abbreviations: epl = epandrial lobe; epn = epandrium; hp = hypoproct process; hyp = hypandrium; ph = phallus; sur = surstylus; s 8 = sternite 8; t 8 = tergite 8.