Species of the genus Chrysotimus Loew from China (Diptera, Dolichopodidae)

Abstract The following three species are described as new to science: Chrysotimus dalongensis sp. n., Chrysotimus huairouensis sp. n., and Chrysotimus hubeiensis sp. n., Chrysotimus apicicurvatus Yang, is recorded from Palaearctic China for the first time. A key to the Chinese species of the genus is presented.


Introduction
The genus Chrysotimus Loew, 1857 belongs to the subfamily Peloropeodinae. The genus is distributed worldwide except the Afrotropical region with 67 known species, 14 species are known from the Palaearctic, 25 species from the Oriental (Yang et al. 2006). Thirty-three species are known from China including those newly described herein. Guzeriplia Negrobov, 1968, embodies the characters of Chrysotimus Loew in the head and thorax with the yellow hairs and bristles and biseriate acr. Thus, it was synonymized with Chrysotimus by Yang et al. (2006).

Materials and methods
Specimens were studied and illustrated with a ZEISS Stemi 2000-c stereo microscope. Genitalic preparations were made by macerating the apical portion of the abdomen in warm 10% NaOH for 17-20 min, after examination it was transferred to 75% alcohol and stored in a microvial pinned below the specimen. All specimens are deposited in the Entomological Museum of China Agricultural University (CAU), Beijing, China.

Abbreviations are as follows:
acr acrostichal bristles ad anterodorsal bristles av anteroventral bristles dc dorsocentral bristles LI fore leg LII mid leg LIII hind leg oc ocellar bristles pd posterodorsal bristles pv posteroventral bristles v ventral bristles CuAx ratio length of m-cu / length of distal portion of CuA.
Diagnosis. Body with yellow or brownish hairs and bristles, small first flagellomere, most males with hind tarsomere 1 bearing several short black ventral bristles at base, and males with mid tarsomere 1 at least as long as the total of corresponding tarsomeres 2-4, male genitalia with 1-2 subepandrial processes, lateral epandrial lobe distinct. Hind tibia with 2 pd; hind tarsomere 1 with 4-5 short black ventral bristles; surstylus slender (Fig. 8)  Head metallic green with gray pollen; frons and face brilliant. Hairs and bristles on head yellow. Ocellar tubercle weak, with 2 very long oc and 2 very short posterior hairs. Lower postocular bristles (including ventral hairs) pale. Antenna (Fig. 1) black-ish; first flagellomere blackish, rather short, about 0.5 times as long as wide; arista dorsal, with basal segment very short. Proboscis brown, with brown hairs; palpus pale yellow, with pale hairs and 2 pale yellow apical bristles.

Key to species (males) from China
Thorax metallic green with pale gray pollen, mesonotum and scutellum brilliant. Hairs and bristles on thorax yellow; 6 dc, 5-6 irregularly paired acr short and hair-like; scutellum with 2 pairs of bristles. Propleuron with 1 pale bristle on lower portion. Legs including coxae yellow with 5th tarsomere brown. Hairs and bristles on legs yellow; coxae with yellowish hairs and bristles; fore coxa with 3-4 anterior and apical bristles, mid coxa with 2-3 anterior and apical bristles, hind coxa with 1 brown outer bristle near middle. Mid femur with 1 av apically; hind femur with 1 short av and 1 short pv apically. Mid tibia with 2 ad and 2 pd, apically with 4 bristles; hind tibia with 2 ad and 2 pd, apically with 3 bristles. Fore and mid tarsomere 1 each with row of 6-7 v. Hind tarsomere 1 with 6-8 short and thick black ventral bristles at base, and row of 5-6 pv. Distribution. Known only from the type locality in Hubei.

Remarks.
This new species is similar to Chrysotimus acutatus Wang, Yang & Grootaert, but may be separated from the latter by 2 ad on hind tibia, and and by the long, wide, trifurcated lateral process on epandrium. In C. acutatus, the hind tibia has 1 ad, and the lateral epandrial process is short and bifurcated (Wang et al. 2005).
Abdomen metallic green with pale gray pollen, dorsum brilliant, sterna 1-4 yellow. Hairs and bristles on abdomen yellow.
Distribution. Known only from the type locality in Beijing.

Remarks.
This new species is similar to Chrysotimus dorsalis Yang, but may be separated from the latter by the single row of v on the hind tibia, and slender surstylus. In C. dorsalis, the hind tibia lacks row of v, and the surstylus is wide (Yang 2001).
Male genitalia (Fig. 8) dark brown: Epandrium distinctly longer than wide, apically with short and wide lateral process, process acute apically; surstylus slender and finger-like; cercus short and thick, with round apex.
Distribution. Known only from the type locality in Hubei.
Remarks. This new species is similar to Chrysotimus lijianganus Yang & Saigusa, but may be separated from the latter by 2 pd on hind tibia, 4-5 black ventral bristles on hind tarsomere 1, and slender, finger-like surstylus. In C. lijianganus, the hind tibia has 1 pd, hind tarsomere 1 has 7-8 black ventral bristles at base, and the surstylus is very wide (Yang and Saigusa 2001b).
Etymology. The specific epithet derives from the type locality Hubei.