Medetera ganshuiensis, Tang, Chufei, Wang, Ning & Yang, Ding, 2016

Tang, Chufei, Wang, Ning & Yang, Ding, 2016, New species of Medetera from Inner Mongolia, China (Diptera, Dolichopodidae, Medeterinae), ZooKeys 604, pp. 117-144 : 129-130

Taxon classification Animalia Diptera Dolichopodidae

Medetera ganshuiensis sp. n. Figs 5, 18-19, 34

Diagnosis.

Width of face about two times length of first flagellomere. Four pairs of dc, anterior two weak and posterior two strong, one biseriate acr. CuAx ratio 1.4. Hind tibia slightly expanded at apex, with five short black apical spurs. Ventral surstylus with two long strong bristles at apical 1/5. Hypandrium narrowed towards tip, sharp apically, thin and simple in lateral and ventral view. Cercus nearly rectangular, two times longer than wide, with one blade-like bristle apically.

Description.

Male (Fig. 5). Body length 2.5 mm, wing length 2.5 mm. Head: vertex, frons and face dark metallic green with gray pollinosity; eyes separated, face nearly parallel, width of face about twice length of first flagellomere. Hairs and bristles on head black except postocular bristles black and posteroventral hairs pale yellow. Antenna (Fig. 18) all black; first flagellomere pale white pubescent; arista apical, black, thinly pale white pubescent, nearly bare, with basal segment extremely short, less than 0.1 times length of apical segment. Proboscis dark brown with several radial black strips; palpus black with one brown apical bristles.

Thorax dark metallic green with gray pollinosity. Hairs and bristles on thorax black. Four pairs of dc, anterior two weak and posterior two strong, one biseriate acr at anterior portion, two sa. Scutellum with two pairs of sc (median pair long, strong). Legs mainly black except tip of femora dark yellow and extreme base of mid tibia dark yellow. Hairs and bristles on legs mainly pale white. Fore coxa with one anterior bristle at middle and four ventral apical hairs; mid coxa with two outer bristles at middle; hind coxa with one outer bristle at middle. Hind femur with row of three short av at basal 1/3 to apical 1/3. Fore tibia without distinct bristle; mid tibia with one brown apical bristle; hind tibia slightly expanded at apex, without distinct bristle but with five short black apical spurs. Relative length of tibia and five tarsomeres of legs LI: 3.5: 1.5: 1.3: 1.0: 0.5: 0.4; LII: 5.0: 2.2: 2.0: 1.0: 0.4: 0.5; LIII: 5.5: 1.0: 2.5: 1.5: 0.6: 0.6. Wing nearly hyaline, tinged brown; veins brown, R4+5 and M1+2 convergent apically. CuAx ratio 1.4. Squama pale white with pale hairs. Halter pale yellow.

Abdomen dark metallic green with thin gray pollinosity. Hairs and bristles pale yellow. Tergite 2 with one circulate of bristles apically. Male genitalia (Figs 19, 34): Mainly black. Hairs and bristles mainly pale white except two long strong bristles at apical 1/5 of ventral surstylus black. Epandrium longer than wide; epandrial lobes forming one digitation with two long slender apical bristles. Ventral surstylus long, narrowed towards tip, almost straight, dilated at basal 1/2, with two long strong bristles at apical 1/5 portion (one bristle at apical 1/8, one bristle at apical 1/10); dorsal surstylus thin, slightly narrowed towards tip, wide and U–shaped apically, dorsal lobe with three short weak bristles, ventral lobe with one long, straight bristle at tip; lobes both sharp at apex. Cercus nearly rectangular, somewhat wave-like at base, nearly two times longer than wide, with one blade-like bristle apically; covered with thin bristles, but marginal bristles distributed averagely. Hypandrium narrowed towards tip, sharp apically, thin and simple in lateral and ventral view. Phallus hidden in hypandrium.

Female. Unknown.

Types.

Holotype male, CHINA, Inner Mongolia, Helan Mountain, Gulaben, Ganshu Bay (N38°59.165', E106°02.255'), 2300 m, collected by sweeping nets in grass, 2010.VIII.9, Lihua Wang (CAU). Paratype: one male, same data as holotype (CAU).

Distribution.

Palaearctic: China (Inner Mongolia).

Remarks.

This new species is somewhat similar to Medetera mongolica Negrobov, 1966 because their legs are both mainly black, they both almost do not have acr and their cercus both have one strong apical bristle, but can be distinguished from the latter by the bristle of surstylus and the shape of cercus. In Medetera mongolica , one of the apical bristles of dorsal surstylus is flagellate and the cercus has a ventral process ( Negrobov and Stackelberg 1972: p 319, figs 669-672).

Etymology.

The species is named for the type locality, Ganshu.