Descriptions of four new species of <i>Chrysotimus</i> Loew from Tibet (Diptera: Dolichopodidae)

The genus Chrysotimus Loew, 1857 belongs to the subfamily Peloropeodinae. The genus is generally characterized by the yellow or yellowish hairs and bristles, small first flagellomere, hind tarsomere 1 in most males bearing several short erect black ventral bristles at base, and mid tarsomere 1 in male at least as long as tarsomeres 2–4. 60 species were known to occur in the Holarctic and Oriental Realms. Previously, there were 8 species known from the Palaearctic (Negrobov 1991) and 2 species from the Oriental Realms (Becker 1922, Dyte 1975). So far 25 species have been known from China (Parent 1944, Wang et al. 2005, Yang 2001, Yang & Saigusa 2001a, 2001b, 2005, Zhang et al. 2003). Guzeriplia Negrobov, 1968 embodies the characters of Chrysotimus Loew in the head and thorax with yellow hairs and bristles and biseriate acr. However, in Guzeriplia, the hypopygium is large (almost as long as abdomen), bearing the long surstylus and cercus. Bickel (2004) noted that it should be within the range of variation of the latter, probably as a synonymy. In this paper, we describe four species new to science, all found from Tibet, an area lying in the Southwest of China, on the northern side of Himalayas, and bordered with Pakistan, India, Burma, Nepal, and Bhutan. The area belongs to the Palaearctic and Oriental Realms. Perhaps the high-altitude climate is responsible for the restricted occurrence of these four species. We also provide a key to Chrysotimus species males from China.