Chrysotus motuoensis, Liu, Ruosi, Wang, Mengqing & Yang, Ding, 2013

Liu, Ruosi, Wang, Mengqing & Yang, Ding, 2013, Chrysotus Meigen (Diptera: Dolichopodidae) from Tibet with descriptions of four new species, Zootaxa 3717 (2), pp. 169-178 : 173-176

3. Chrysotus motuoensis sp. nov.

( Figs 3 , 9–11 )

Diagnosis. First flagellomere subtriangular, 1.3 times wider than long. All trochanters yellow; fore femur brown with yellow base and apex, hind femur brown with basal 1/3 yellow.

Description. Male. Body length 2.2 mm, wing length 2.1 mm.

Head metallic green with pale gray pollinosity; eyes contiguous on face. Hairs and bristles on head black except postero-ventral hairs pale. Antenna brown; first flagellomere subtriangular, 1.3 times wider than long; arista brown, short pubescent ( Fig. 9 ). Proboscis brown with brown hairs; palpus yellow with 1 brown bristle.

Thorax metallic green with pale gray pollinosity. Hairs and bristles on thorax black; 6 dc, 6–7 irregularly paired acr short and hair-like; scutellum with 2 pairs of bristles, basal pair short and hair-like, lateral pair long; proepisternum with 1 long black bristle on lower part and 1 short black bristle on upper part.

Legs mainly brown except all trochanters yellow; base and apex of fore femur yellow, especially ventral side with more yellow base and apex, basal 1/4 and apical 1/5 of mid femur yellow, basal 1/3 of hind femur brown yellow; fore and mid tibiae yellow, hind tibia yellow to dark brown from base to apex. Fore and mid tarsi from tip of tarsomere 1 onward black. Hairs and bristles on legs black. Hind coxa with 1 black outer bristle at base. Fore tibia apically with 3 short bristles. Mid tibia with 2 strong ad at basal 1/5 and 1/3; apically with 4 bristles. Hind tibia with 2 ad at basal 1/4 and 1/2; apically with 3 bristles. Relative length of tibia and 5 tarsomeres of legs LI: 4.7: 2.5: 1.3: 0.8:?:?; LII: 6.2: 3.2: 1.8: 1.3: 0.7: 0.7; LIII: 6.5: 2.0: 2.0: 1.3: 0.8: 0.8.

Wing hyaline, tinged brown ( Fig. 3 ); veins blackish, R4+5 and M parallel apically; CuAx ratio 0.3. Squama yellow with yellow hairs. Halter pale yellow.

Abdomen metallic green with pale gray pollinosity; hairs and bristles on abdomen black. Male genitalia ( Figs 10, 11 ): Epandrium somewhat rounded, without angular projection posteriorly. Lateral epandrial lobe protruded and wide. Surstylus somewhat long and curved, with acute end. Cercus short and wide, with moderated bristles. Apex of phallus with 2 sheet-liked structure, one short and other relatively long.

Female. Unknown.

Specimens examined. HOLOTYPE ♂, China, Tibet, Linzhi, Motuo, 80K, 29°33′N, 95°32′E, 1000 m, 2012. VIII.5–10, X.K. Li.

Distribution. China (Tibet).

Etymology. The specific epithet refers to locality of the holotype Motuo.

Remarks. The new species is similar to Chrysotus brevicercus Wang & Yang in the first flagellomere subtriangular, 1.3 times wider than long, and the CuAx ratio 0.3, but can be separated from the latter by apex of phallus with 2 sheet-liked structure. In C. brevicercus , the apex of phallus is a blunt protruding (Yang et al. 2011).

4. Chrysotus namaicunensis sp. nov. ( Figs 4 , 12–14 )

Diagnosis. First flagellomere subtriangular, 1.6 times wider than long. Hind femur yellow with apical 1/5 black; hind tibia yellow with apical 1/5 black.

Description. Male. Body length 1.9 mm, wing length 1.9 mm.

Head metallic green with pale gray pollinosity; eyes contiguous on face. Hairs and bristles on head black, postocular bristles (including postero-ventral hairs) pale. Antenna brown; first flagellomere subtriangular, 1.6 times wider than long; arista brown, short pubescent ( Fig. 12 ). Proboscis brown with pale hairs; palpus pale with hairs and bristles.

Thorax metallic green with pale gray pollinosity. Hairs and bristles on thorax black; 5 strong dc, 6–7 irregularly paired acr short and hair-like; scutellum with 2 pairs of bristles, basal pair short and hair-like, lateral pair long; proepisternum with 1 long black bristle on lower part and 1 short black bristle on upper part.

Legs mainly yellow except base of fore coxa, entire mid coxa, and hind coxa (excluding tip) black; apical 1/5 of hind femur and tibia black; fore and mid tarsi from tip of tarsomere 2 onwards brown, hind tarsus black except basal 1/3 of tarsomere 1. Hairs and bristles on legs mostly black, fore coxa with brown hairs. Fore coxa with rows of hairs; mid coxa with 2 bristles; hind coxa with 1 black outer bristle at base. Fore tibia with 1 pd at basal 1/3; apically with 4 bristles. Mid tibia with 3 ad (basal one weak and other 2 strong, 2 strong ad at basal 1/5 and 1/2, 1 weak ad at basal 1/6), 2 short pd (one at basal 1/5 and other at 1/2); apically with 4 bristles. Hind tibia with 2 ad (at basal 1/5 and 1/2) and 3 pd; apically with 4 bristles. Relative length of tibia and 5 tarsomeres of legs LI: 4.0: 2.0: 1.0: 0.8: 0.5: 0.5; LII: 5.0: 3.0: 1.4: 1.0: 0.7: 0.7; LIII: 6.2: 2.0: 1.5: 1.0: 0.7: 0.7.

Wing hyaline ( Fig. 4 ); veins blackish, R4+5 and M parallel apically; CuAx ratio 0.2. Squama yellow with pale hairs. Halter pale.

Abdomen metallic green with pale gray pollinosity; hairs and bristles on abdomen black. Male genitalia ( Figs 13, 14 ): Epandrium somewhat rounded, without angular projection posteriorly. Lateral epandrial lobe moderately long, with 3 hairs at apex. Surstylus wide basally, somewhat tapered apically. Cercus flattened, with moderately long bristles. Apex of phallus round.

Female. Unknown.

Specimens examined. HOLOTYPE ♂, China, Tibet, Linzhi, Namaicun, 29°73′N, 94°73′E, 3200 m, 2012. VIII.8, W.L. Li.

Distribution. China (Tibet).

Etymology. The specific epithet refers to locality of the holotype Namaicun.

Remarks. The new species is similar to Chrysotus cilipes Meigen in apex of phallus round, but can be separated from the latter by the mid tibia with 3 ad and lateral epandrial lobe relatively long. In C. cilipes , the mid tibia has 2 ad, and the lateral epandrial lobe is short (Yang et al. 2011).

Figures

FIGURES 1 – 5. habitus photographs: 1, Chrysotus altavaginas sp. nov. (male), scale bars = 0.5 mm; 2, Chrysotus biprojicienus Wei & Zhang, scale bars = 0.5 mm; 3, Chrysotus motuoensis sp. nov. (male), scale bars = 0.5 mm; 4, Chrysotus namaicunensis sp. nov. (male), scale bars = 0.5 mm; 5, Chrysotus tibetensis sp. nov. (male), scale bars = 0.5 mm.

FIGURES 9 – 11. Chrysotus motuoensis sp. nov. (male): 9, antenna, lateral view, scale bars = 0.1 mm; 10, genitalia, lateral view, scale bars = 0.1 mm; 11, apex of phallus, ventral view, scale bars = 0.05 mm.

FIGURES 12 – 14. Chrysotus namaicunensis sp. nov. (male): 12, first flagellomere, lateral view, scale bars = 0.1 mm; 13, genitalia, lateral view, scale bars = 0.1 mm; 14, apex of phallus, lateral view, scale bars = 0.05 mm.