Hybos biancistroides, Yang & Li, 2011

Yang, Ding & Li, Weihai, 2011, Two New Species of Hybos Meigen from Oriental China (Diptera, Empidoidea, Hybotidae), Revue suisse de Zoologie 118 (1), pp. 93-98 : 94-95

Hybos biancistroides sp. n. Fig. 1

HOLOTYPE: Male, Hubei, Shennongjia, Yinyuhe , 18. VII. 2009, Qifei Liu ( CAU) . PARATYPES: 4 males, same data as holotype ( CAU & MHNG) .

ETYMOLOGY: The specific name refers to two hook-like processes of the left surstylus.

DIAGNOSIS: Legs entirely black. Mid femur with one row of long, uniformly light brown pv setulae. Right surstylus thick and apically hooked medially; left surstylus with two medially directed hook-like processes, a short basal and apically a very long, medially directed one.

DESCRIPTION MALE: Body length 3.2-3.3 mm, wing length 3.2-3.3 mm.

Head: black, pale gray microtrichose. Eyes contiguous on frons; upper facets distinctly enlarged. Setae and setulae on head black; ocellar tubercle distinct, with one pair of long oc. Antenna black; scape bare; pedicel with a circle of subapical setulae; first flagellomere without dorsal setulae, 1.6-1.7 times as long as wide; arista black, 3.6-3.7 times as long as first flagellomere, short pubescent (longest rays shorter than basal diameter of arista) except apical 1/4 thin and bare. Proboscis black; palpus black with 3-4 long ventral setulae.

Thorax: black, pale gray microtrichose. Setae and setulae black; postpronotal lobe setulose but true h absent, 2 npl (anterior npl short), acr irregularly biseriate, 1 distinct posterior dc and 5-6 setulae anteriad, 1 weak presc, 1 long psa; scutellum with 2 (pairs of) short lateral setulae, 1-2 (pairs of) short apical setulae and 1 (pair of) long subapical setae. Legs entirely black. Setulae on legs light brown, setae black, except tibiae and tarsi with mostly black setulae. Fore femur 1.2 times as wide as mid femur, with one row of long pv setulae; mid femur with 1 preapical anterior seta and with one row of long pv setulae; hind femur 2.0-2.1 times as wide as mid femur, with 3-4 ad setae in apical half, and with 7-8 av (longer than v and pv), 14 v (6 sparse v on basal 1/2 and 8 dense v on apical 1/2), a short row of 3-5 pv on basal 1/4, which are spinelike and inserted on weak tubercles. Fore tibia with 1 long ad at middle, apically with 1 ad and 1 av; mid tibia with 3 long ad in one row, apically with 4 setae (1 av very long); hind tibia apically with 1 brownish yellow av and 1 long, thin preapical ad. Mid tarsomere 1 with two rows of short v; hind tarsomeres 1-2 with short ventral spines. Wing hyaline or indistinctly grayish tinged; stigma dark brown; veins dark brown, R 4+5 and M 1 slightly divergent apically. Squama yellow, bordered with pale setulae. Halter pale yellow with dark brown base.

Abdomen: weakly curved downward, blackish, grey microtrichose. Setulae and setae pale, but few setae on hypopygium black.

Male genitalia (Fig. 1): right epandrial lobe wide with slightly concave inner margin at middle, right surstylus thick, its tip with a medially directed hook-like process; left epandrial lobe narrow with slightly convex inner margin, left surstylus long with a short basal and a long apical hook-like process, both medially directed; hypandrium distinctly longer than wide, apically distinctly narrowed toward extreme tip.

FEMALE: Unknown.

DISTRIBUTION: China (Hubei).

FIG. 1 Hybos biancistroides sp. n. (male). (A) Genitalia, dorsal view. (B) Hypandrium, ventral view.

REMARKS: In the key of Yang & Yang (2004) this species runs to couplet 52 which has to be modified as follows:

52. Wing hyaline or indistinctly grayish tinged......................... 52a Wing grayish..................................... H. jianfengensis

52a. First flagellomere with several dorsal setae; arista entirely bare...................................................... H. tongshanensis First flagellomere without any dorsal seta; base of arista pubescent............................................... H. biancistroides sp. n.

The new species may be confused with Hybos tongshanensis Yang & Yang, 1991 from Hubei and Guangxi, but it can be easily separated from the latter by having the first flagellomere without any dorsal seta and the base of the arista pubescent. In H. tongshanensis, the first flagellomere has several dorsal setae, and the arista is entirely bare ( Yang & Yang, 2004). Another morphologically similar species is H. yinyuhensis sp. n. (see below). The differences between the two species are given under this species.