Hybos flavitibialis, Li, Zhu, Wang, Ning & Yang, Ding, 2014

Li, Zhu, Wang, Ning & Yang, Ding, 2014, New species of Hybos Meigen from Northwest China (Diptera: Empidoidea, Hybotinae), Zootaxa 3786 (2), pp. 166-180 : 170-171

3. Hybos flavitibialis sp. nov.

( Figs 5–8 )

Diagnosis. Arista bare. Wing hyaline; stigma faint; R4+5 and M1 weakly divergent apically. Legs black except apex of hind femur and base of hind tibia yellow, mid tibia yellow; mid and hind tarsi brown except tarsomeres 1–2 yellow. Right surstylus short and wide, apically with subtriangular incision. Hypandrium apically nearly truncate Description. Male. Body length 3.5 mm, wing length 3.5 mm.

Head black with pale gray pollinosity. Eyes contiguous on frons, dark yellow with enlarged upper facets. Setulae and setae on head black; ocellar tubercle distinct, with 2 long oc and 2 short posterior setulae. Antenna black; scape without setulae, pedicel with circlet of subapical setulae; first flagellomere without dorsal setula; arista black, bare, apical 1/5 or so thin. Proboscis nearly as long as head, blackish. Palpus blackish, with 6 ventral setulae.

Thorax black with pale gray pollinosity. Setulae and setae on thorax black, setulae rather short; ppn absent, 2 npl (posterior npl long); uniseriate dc short setula-like, nearly as long as irregularly quadriseriate acr, 1 long prsc, 1 psa shorter than prsc; scutellum with 8 very short marginal setulae (2 setulae located between sc) and 2 long sc. Legs black except apex of hind femur and base of hind tibia yellow, mid tibia yellow; mid and hind tarsi brown except tarsomeres 1–2 yellow. Setulae on legs blackish and setae black. Fore femur 1.3 times and hind femur 2.5 times as wide as mid femur. Fore and mid femur each with row of 4–5 thin pv, but those on mid femur relatively long. Hind femur with 4 long apical ad and nearly three rows of spinose ventral setae on tubercles (av relatively long). Fore tibia apically with 1 long ad and 1 long pv. Mid tibia with 2 very long ad and 1 very long pv, apically with 4 long setae (1 pv very long). Hind tibia apically with 1 long thin brown pd. Fore tarsomeres 1–2 with some long thin setulae. Hind tarsomeres 1–2 with short spinose ventral setae. Wing hyaline; stigma indistinct; veins brown, R4+5 and M1 weakly divergent apically. Squama yellow with pale yellow setulae. Halter dark yellow.

Abdomen slightly curved downwards, subshiny blackish with pale gray pollinosity; hypopygium indistinctly swollen. Setulae and setae on abdomen black.

Male genitalia ( Figs 5–8 ). Left epandrial lamella nearly as long as right epandrial lamella, with weakly convex inner margin near middle; left surstylus long thick but apically nearly acute, with short wide basal process irregular in shape. Right epandrial lamella relatively narrow with weakly convex inner margin near base; right surstylus short and wide, apically with subtriangular incision. Hypandrium rather wide, slightly longer than wide, with wide and slightly oblique apical margin bearing long setulae.

Female. Body length 3.5–3.8 mm, wing length 3.8–4.2 mm. Similar to male. Female terminalia: Tergite 8 well developed, strongly extended downward and ventrally fused, loop-like, ventrally with V-shaped apical incision. Tergite 10 nearly quadrate. Cercus basally wide, apically tapering and slightly curved downwards. Sternite 8 apically rounded with 2 close spinose setae at middle.

Type material. HOLOTYPE ♂, CHINA, Tibet, Nyingchi (N29°39′ 6.53″ E94°21′ 37.17″), Beibeng, 2011. VIII.11, L.H. Wang. PARATYPES: 2 ♀, same data as holotype.

Remarks. The new species is similar to H. similaris Yang & Yang from Guizhou and Zhejiang, but it may be separated from the latter by the following characters: legs partly yellow, wings hyaline, left and right surstyli rather wide with irregular incision. In H. similaris , the legs are entirely black; the wing is grayish; the left and right surstyli are relatively narrow without incision ( Yang & Yang 2004).

Etymology. The specific name refers to the yellow mid tibia.

Figures

FIGURES 5 – 8. Hybos flavitibialis sp. nov. (male). 5. Genitalia, dorsal view; 6. right surstylus; 7. left surstylus; 8. hypandrium, ventral view. Scale bar = 0.1 mm.