Chrysosoma zengchengense, Zhu & Yang, 2005

Zhu, Yajun & Yang, Ding, 2005, New species of Chrysosoma Guérin-Méneville (Diptera: Dolichopodidae), with a key to Chinese species, Zootaxa 1029 (1), pp. 47-60 : 55-57

Chrysosoma zengchengense sp. nov.

( Figs. 8–10 )

Diagnosis. Antenna black; arista with lanceolate apical flag; frons with 1 long pale hair on postero­lateral slope; CI blackish, CII and CIII black; FI with row of spine­like ventral bristles (the longest bristles 3 times as long as width of FI).

Description. Male body length 5.0– 5.2 mm, wing length 5.3–5.5 mm.

Head metallic green with pale gray pollen; vertex distinctly excavated, frons subshining. Hairs and bristles on head black; middle and lower postocular bristles (including postero­ventral hairs) pale; frons with 1 long pvt and 1 long pale hair on postero­lateral slope, ocellar tubercle with 2 long strong oc. Antenna black; scape somewhat swollen; pedicel with circlet of apical bristles (including 1 long thick dorsal and 1 long thick ventral bristles); first flagellomere triangular, nearly as long as wide; arista apical, black, with lanceolate apical flag ( Fig. 8 ), much longer than head + thorax. Proboscis yellow with brownish hairs; palpus dark brown with brown hairs and 2 black bristles.

Thorax metallic green with pale gray pollen. Hairs and bristles on thorax black; 2 strong posterior dc and 3 anterior hairs; 3 long irregularly paired acr; scutellum with 2 pairs of sc, basal pair weak. Legs yellow; CI blackish, CII, CIII and trochanters black; It 2­5 and IIt 2 brown, IIt 3­5 and IIIt 2­5 dark brown. Hairs and bristles on legs black; coxae with pale hairs, CI with lateral hairs and 2 spine­like apico­lateral bristles; CII with lateral hairs, and 2 spine­like apico­lateral bristles; CIII with group of outer long pale hairs. Femora long with pale ventral hairs; FI with row of spine­like ventral bristles (the longest bristles 3 times as long as width of FI); FII and FIII with row of long hair­like av and pv. TI with 2 ad and 1 pv at apical 1/5, apically with 2 short bristles; TII with 1 ad at basal 1/6, 1 long av at basal 1/6 and 2 short av, apically with 1 long and 2 short bristles; TIII with 2 ad, 6 – 7 pv, apically with 2 long and 1 short bristles. It 1 somewhat flattened with very short dense ventral pubescence on basal 4/5 ( Fig. 9 ); IIt 2 with 5 av and 5 pv; IIIt 1 with 1 av at extreme base. Relative lengths of tibia and tarsomeres: LI 2.5: 1.6: 0.7: 0.5: 0.3: 0.2; LII 3.9: 2.9: 1.8: 0.7: 0.3: 0.2; LIII 5.5: 2.2: 1.1: 0.8: 0.4: 0.3. Wing: hyaline, tinged with brown; veins dark brown, M 1 concave, crossvein m­cu straight. Squama dark yellow, margin pale with pale hairs. Halter yellowish with yellow knob.

Abdomen dark metallic green with gray pollen. Hairs and bristles on segments 1–4 pale, but sterna 5 – 7 with black bristles.

Male genitalia ( Fig. 10 ): Epandrium much longer than wide with 1 lateral hair; surstylus rather thick, basally with a short finger­like lateral process; hypandrium with narrow left lateral arm, nearly reaching apex of aedeagus; cercus furcate, with long black bristles.

Female. Unknown.

Type material. Holotype male, Guangdong: Zengcheng, Nankunshan , 23°18’N, 113°49’E, 14. 07. 2003, leg. Xingyue Liu. Paratypes 2 males, same data as holotype but leg. Shuwen An ; 1 male, same data as holotype but 15. 07. 2003, leg. Shuwen An.

Distribution. China (Guangdong).

Etymology. The specific name refers to the type locality Zengcheng.

Remarks. The new species is very similar to C. hainanum , but can be easily recognized by the following characters: fore coxa blackish, male cercus furcated; in C. hainanum , fore coxa yellow, male cercus long and finger­like.

Figures

FIGURES 8–10. Chrysosoma zengchengense sp. nov. (Male). 8. Antennal flag, lateral view; 9. left It1, right lateral view; 10. genitalia, lateral view.