Hercostomus galonglaensis, Tang, Chufei, Zhang, Lili & Yang, Ding, 2014

Tang, Chufei, Zhang, Lili & Yang, Ding, 2014, New species of Hercostomus baishanzuensis group from Tibet (Diptera: Dolichopodidae, Dolichopodinae), Zootaxa 3881 (6), pp. 549-562 : 559-560

Hercostomus galonglaensis sp. nov.

( Figs 5, 6 , 18, 19 )

Diagnosis. First flagellomere pointed at tip. Basal segment of arista 0.15 times as long as apical portion of arista ( Fig. 18 ). Cercus nearly square, nearly as wide as epandrium, with an incision at base ( Fig. 19 ).

Description. Male ( Fig. 5 ). Body length 2.8 mm, wing length 3.2 mm. Head dark metallic green, with thick pale pollinosity; face gradually narrowed downward. Hairs and bristles on head black, postocular bristles and posteroventral hairs black. Antenna black ( Figs. 18 ), but first flagellomere somewhat brownish except basal portion; first flagellomere pointed at tip, 1.6 times longer than wide, with brown pubescence; arista subapical, shorter than head width, black, almost bare, basal segment 0.15 times as long as apical portion of arista. Proboscis brown with brown hairs; palpus dark brown, with yellowish hairs and 3 black dorsal bristles. Thorax metallic green, with pale gray pollinosity. Hairs and bristles on thorax black; 6 long and strong dc, 6 pairs of long hair-like acr. Scutellum with 2 pairs of long strong sc. Legs mainly black, but trochanters, bases of femora and mid portions of tibiae yellow, apical half of fore tarsomere 1 somewhat brownish, apical half of mid tarsomere 1 yellow. Hairs and bristles on legs black. Coxae anteriorly with rows of irregular bristles. Mid and hind coxae each with 1 outer bristle. Mid trochanter apically with 1 weak bristle. Hind trochanter with 1 weak outer bristle. Fore femur with row of 9 d, 1 preapical av. Mid femora with 1 strong pv. Fore tibia with 3 ad, 2 pd, 6 short pv at apical half and 3 apical bristles. Mid tibia with 2 ad, 3 pd, 1 av and with 3 apical bristles. Hind tibia with 5 ad, 1 pd, 1 av and 2 apical bristles. Tibia and 5 tarsomeres of legs LI: 2.0: 1.0: 0.5: 0.5: 0.2: 0.3; LII: 3.0: 1.0: 0.8: 0.6: 0.4: 0.3; LIII: 2.8: 1.0: 1.2:?:?:?; LIII mostly broken. Wing nearly hyaline, tinged brown; veins brown, R4+5 and M1+2 slightly convergent apically. CuAx ratio 0.6. Squama pale yellow with 8 black hairs. Halter pale yellow. Abdomen metallic green, with pale gray pollinosity. Hairs and bristles on abdomen black. Male genitalia ( Fig. 19 ): Epandrium distinctly longer than wide. Outer epandrial lobe thin, long, with thickened tip, with 2 bristles at tip and 1 long bristle at middle. Inner surstylus bifurcated at middle, ventral arm long with 1 short bristle at base, dorsal arm short with 1 bristle at tip; outer surstylus thicker, pointed at tip, with inner margin jag-like at apical half and outer margin bearing an incision. Cercus nearly square, nearly as wide as epandrium, with several digitations, with an incision at base, bristles long. Hypandrium with 1 weak inner tooth. Phallus thin, straight, distinctly longer than hypandrium. Female ( Fig. 6 ). Body length 3.0 mm, wing length 3.2 mm. Very similar to male, but first flagellomere nearly as long as wide. Halter pale. Middle portions of tibiae dark yellow.

Type material. HOLOTYPE, ♂ labeled: China: Tibet, Bomi, Galongla Mountain (N29°53'00.7" E95°46'03.4"), 3166 m, collected from meadow and bosk, 2013. VII.13, Xiaoyan Liu ( CAU). PARATYPES: 1 ♂ 1 ♀, same data as holotype.

Distribution. Oriental: China (Tibet).

Remarks. The new species is somewhat similar to H. hunanensis (Yang) from Hunan of China, but may be separated from the latter by the cercus which is as wide as epandrium. In H. hunanensis , the cercus is relatively narrow ( Yang 1997a).

Etymology. The species is named after the type locality Galongla Mountain.

Figures

FIGURES 5 – 6. Hercostomus galonglaensis sp. nov. 5. Male; 6. Female. Scale bar = 1.0 mm.

FIGURES 18 – 19. Hercostomus galonglaensis sp. nov., male. 18. Antenna, scale bar = 0.2 mm; 19. Genitalia, lateral view, scale bar = 0.3 mm. Abbreviations: epn = epandrium, hyp = hypandrium, ph = phallus, sur = surstylus, lat = epandrial lobe, cer = cercus.