Chrysotus anshunus, Wei, Lianmeng & Zhang, Lili, 2010

Wei, Lianmeng & Zhang, Lili, 2010, A taxonomic study on Chrysotus Meigen (Diptera: Dolichopodidae) from southwest China: descriptions of eleven new species belonging to the redefined C. laesus - group, Zootaxa 2683, pp. 1-22 : 7-8

3. Chrysotus anshunus sp. nov.

( Fig. 3 )

Diagnosis. Eyes contiguous on face. Postocular setae black. Proboscis brown, palpus brownish yellow. All coxae blackish, femora blackish. Squama pale with brown setulae. Halter pale. Male terminalia with end of ventral projection of epandrium hook-like, with acute anterior and posterior angles and surstylus long and curved.

Description. Male: Body length 2.2 mm, wing length 1.5 mm. Head: Metallic green with pale gray pollinosity; eyes contiguous on face. Setulae and setae on head black, postocular setae black. Antenna black; first flagellomere subtriangular ( Fig. 3 B), 0.7 times as long as wide; arista black, minute pubescence. Proboscis brown with black setulae; palpus brownish yellow with 1 black apical seta. Thorax: Dark metallic green with pale gray pollinosity. Setulae and setae on thorax black; 6 strong dc, 7 irregularly paired acr short and setula-like; scutellum with 2 pairs of setae, basal pair short and setula-like; propleuron with 1 black setula and 1 black seta on lower part. Legs: (mid tarsus broken off) yellow, all coxae and trochanters blackish, femora blackish; base of tibiae brownish; fore tarsus from tip of tarsomere 1 onwards brownish, hind tarsus brown except base of tarsomere 1 pale. Setulae and setae on legs black. Mid and hind coxae each with 1 outer seta. Fore femur with 3–4 pv apically, mid femur with 2–3 av apically, hind femur with 3 av apically. Fore tibia with 1 ad, apically with 3 short setae; mid tibia with 2 ad and 2 pd, apically with 4 setae; hind tibia with 2 ad and 4 pd, apically with 4 setae. Relative lengths of tibia and 5 tarsomeres of legs LI 37: 18: 10: 6: 4: 4; LII 45:?:?:?:?:?; LIII 50: 15: 12: 9: 5: 5. Wing: Hyaline, veins brown; R4+5 and M1+2 parallel apically, CuAx ratio 0.28. Squama pale with brown setulae. Halter pale. Abdomen: Dark metallic green with pale gray pollinosity; setulae and setae on abdomen black. Male terminalia ( Fig. 3 A). Epandrium with angular projection posteriorly. End of ventral projection of epandrium with acute anterior angle and hook-like posterior angle; former angle not beyond level of flattened distal margin of lateral epandrial lobe. Lateral epandrial lobe shorter and wider, bearing 2 developed setae and short and weak seta, respectively. Surstylus somewhat long and curved, with acute end. Cercus wide and short, with strong setae. Hypandrium with lateral process pointed apically. Proximal portion of hypandrium with low flat process. Postgonite with strip-like arms and knife-shaped anterior process, all projections subequal in length. Female: Unknown.

Type material. HOLOTYPE ɗ, Guizhou: Anshun, Jiaozishan, 1400 m, 25.VIII.1993, LM Wei.

Etymology. The specific name refers to the type locality of Anshun, Guizhou.

Remarks. In the C. laesus -group, C. fuscitibialis sp. nov. appears closely related to this new species, but can be easily differentiated by the following characters: end of ventral projection of epandrium shrink back to level of flat distal margin of lateral epandrial lobe; hypandrium with ventral process long and acute apically; proximal portion of hypandrium with two projections, one rather small and other quite large.

According to the key of Negrobov et al. (2000), the new species will run to C. nudisetus Negrobov et Maslova, 1995 , but can be separated from the latter by end of ventral projection of epandrium with acute anterior and posterior angles; lateral epandrial lobe with flat distal margin; surstylus longer and bent; hypandrium with ventral process.

Based on the key of Becker (1922), the new species will run to couplet 3, but differs from all species under the couplet by blackish brown femora and yellow tibiae.

Figures

FIGURE 3. Chrysotus anshunus sp. nov. (A) male terminalia, left lateral view; (B) male first flagellomere, lateral view.