Metopia pollenia Chao & Zhang 1988

Metopia pollenia Chao & Zhang, 1988a: 284. China, Sichuan, Xiangcheng, Chaike.

Originally included specimens: Described from two males.

Name-bearing type: Holotype ♂: Sichuan, Xiangcheng, Chaike/ 3000M/ Chinese Academy of Sciences [white label in Chinese, in black print except “Xiangcheng, Chaike/ 3000M” handwritten in black ink]// 1982. VI.20 / Collected by X.Z. Zhang [“1982. VI.20 ” handwritten in black ink, remaining in black print, in Chinese]// HOLOTYPE [red label, in black print]// IOZ(E)216082 [blue label, in black print]// ♂ [white label, in black print]// Metopia / pollenia / Zhao & Zhang [white label, in black print]// Metopia / pollenia Chao et Zhang / Identified by C.M. Chao [“Identified by C.M. Chao” in black print, in Chinese, remaining handwritten in blueblack ink].

Holotype in fair condition.

Additional type specimen: Paratype 1♂: Sichuan, Xiangcheng, alt. 3200m, 26.VI.1982, Coll. by X.Z. Zhang. Specimen in NZMC.

Current identity: Metopia pollenia Chao & Zhang, 1988, as correctly listed by Pape (1996) and as treated by Xue & Chao (1998).

Remarks: This species is similar to M. campestris (Fallén) in general habitus and apparent with identically shaped specialised setae of the fore tarsi. However, the marked differences in the male terminalia are here considered as strong evidence of a specific separation. The phallus of M. pollenia widens apically into a very broad opening (phallotreme), so that the greatest width of the phallus is at the very tip (Fig. 5 B, also Chao & Zhang, 1988a: fig. 14b). The phallus of M. campestris is not particularly widened at the tip, which is much narrower than the width at the level of the ventral plates (see Allen, 1926, fig. 2; Pape, 1987, fig. 149).

Redescription of Male: Body length 4.5–7.0 mm (Fig. 5 A). Eye bare, deep red. Fronto-orbital plate, parafacial and postocular strip black with silvery gray pollinosity; parafacial with one or two black bristles on the upper part, about as broad as fronto-orbital plate. Frontal vitta brown, 2.3× as broad as fronto-orbital plate at the narrowest point; frons at vertex about 0.45× head width (Fig. 5 C); frontal row of 8 or 9 bristles; outer vertical bristle differentiated from postocular bristles, two proclinate orbital and two upper orbital bristles. Ocellar bristles directed antero-laterally. Gena ground color black, with black bristles and silvery gray pollinosity, height 0.1× eye height in lateral view (Fig. 5 E). Antenna brown, almost reaching the level of vibrissal insertion, first flagellomere 3.7× as long as pedicel (Fig. 5 C); arista black and micropubescent, postocular bristles in six rows; vibrissa developed (Fig. 5 D). Palpus yellow with black tip, slightly expanded in distal part.

Thorax ground color black; scutum pollinosity gray with three black dorsal vittae. Chaetotaxy: acrostichals 1+1, dorsocentrals 2+3, intra-alars 0+3, supra-alars 2, postalars 2, postpronotals 2, notopleurals 2, scutellum with 1 apical, 1 subapical and 1 basal bristles. Pleuron with meropleurals 3 or 4, katepisternal bristles 1: 1, prosternum, metasternum, proepisternum and postalar wall bare.

Wing hyaline; subcostal sclerite and basicosta yellow, bare; tegula brown; costal spine not differentiated (Fig. 5 A); vein R1 bare, one ventral and one dorsal setae at node of R2+3-R4+5.

Legs black; fore femur with four or five rows of bristles along dorsal, posterodorsal, posterior and posteroventral margins, fore tibia with one sub-median posterodorsal bristles, fore tarsomeres 1–4 each with one slender bristles (Fig. 5 G); mid femur with one row of anterior bristles and two apical posterodorsal bristles, mid tibia with one sub-median anterodorsal, one sub-median ventral, and three posterodorsal bristles; hind femur with one row of anterodorsal bristles (about 10) and one row of ventral bristles, hind tibia with one row of anterodorsal bristles (about 8) and one row of posterodorsal bristles (about 4) and one median anteroventral bristle.

Abdomen long oval with gray pollinosity; tergites 1+2 entirely black, tergites 3 and 4 with median longitudinal stripe, without any spot, tergite 5 entirely covered with pollinosity and without black marginal band, tergites 4 and 5 with complete row of marginal bristles (Fig. 5 F). Terminalia: Cercus short; phallus widens apically into a very broad opening (phallotreme) (Fig. 5 B).