Hercostomus (Hercostomus) taipeiensis Zhang, Yang and Masunaga

Zhang, Lili, Yang, Ding & Masunaga, Kazuhiro, 2005, (Diptera, Dolichopodidae), Zootaxa 811, pp. 1-8 : 5-6

Hercostomus (Hercostomus) taipeiensis Zhang, Yang and Masunaga , sp. nov.

( Figs. 6–10 )

Diagnosis. — Postocular bristles entirely black. Antenna black; first flagellomere 2.0 times longer than wide, acute apically. Fore tarsi with apical half of tarsomere 4 and entire tarsomere 5 white. Cercus truncate apically.

Description. — Male. Body length 3.8–3.9 mm, wing length 3.7–3.8 mm.

Head metallic green with pale gray pollen. Face narrowing downward, narrower than first flagellomere. Hairs and bristles on head black; postocular bristles entirely black. Antenna ( Fig. 7 ) black; first flagellomere 2.0 times longer than wide, acute apically; arista black, minutely pubescent with basal segment 0.36 times as long as apical segment. Proboscis dark yellow with black hairs; palpus brown with black hairs.

Thorax metallic green with pale gray pollen. Hairs and bristles on thorax black; 6 strong dc, 7 irregularly paired acr; scutellum with one pair of strong bristles. Propleuron black haired with 1 black bristle on lower portion. Legs [hind tarsomeres 2–5 broken off] yellow; fore coxa yellow, mid and hind coxae brown. Fore tarsi from tip of tarsomere 1 onward brown to dark brown, except basal half of tarsomere 4 and tarsomere 5 white. Hairs and bristles on legs black, mid and hind coxae each with 1 outer bristle, mid and hind femora each with 1 anterodorsal preapical bristle; mid femur with 1 preapical pv. Fore tibia with 2 pd, apically with 3 short bristles; mid tibia with 2 ad and 2 pd, apically with 4 bristles; hind tibia with 3 ad and 4 pd, apically with 3 bristles. Relative lengths of tibia and 5 tarsomeres fore leg: 1.7: 1.1: 0.5: 0.35: 0.25: 0.25; mid leg: 2.3: 1.2: 0.7: 0.5: 0.45: 0.45; hind leg: 2.85: 0.75:?:?:?:?. Wing ( Fig. 6 ) hyaline, tinged with grayish; veins brown, R4+5 and M slightly convergent apically; CuAx ratio 0.5. Calypter yellow with black hairs. Halter yellow.

Abdomen metallic green with pale gray pollen, hairs and bristles black. Hypopygium ( Figs. 8–10 ): Epandrium longer than wide with narrow apex; epandrial lateral lobe acute apically with 3 inner bristles; cercus band­like with broad apex bearing 2 strong bristles; hypandrium irregularly furcated.

Female. Unknown.

Type material. — Holotype ď, TAIWAN: Taipei, Wulai, Shiao (24°50'35''N, 121°30'59''E), 350m, sweep net, 8. iv. 1996, I. Sivec and B. Horvat. Paratype: 1ď, TAI­ WAN: Taipei, N Shinpei (24°53'51''N, 121°45'33''E), 400m, sweep net, 7. iv. 1996, I. Sivec and B. Horvat.

Etymology. — The specific name refers to the type locality Taipei ( Taiwan).

ventral view.

Comments. — The new species belongs to the Hercostomus subnovus ­group (Yang and Saigusa 2001), in the cercus with 2 strong inner apical bristles. The subnovus ­group includes 21 species from continental China, and this is the first record of this speciesgroup from Taiwan. The new species is somewhat similar to H. polleti Yang and Saigusa in the first flagellomere acute apically and cercus truncate apically, but may be separated from the latter by the entirely metallic green thorax and abdomen, and epandrium obtuse apically. In H. polleti , the thorax laterally and abdomen basally are partly yellow, and the epandrium is acute apically ( Yang and Saigusa 1999).

Figures

FIGURES 6 – 10. Hercostomus (Hercostomus) taipeiensis sp. nov. (male). 6. Wing; 7. antenna, lateral view; 8. hypopygium (excluding cercus), lateral view; 9. cercus, lateral view; 10. hypandrium,