Chrysotus laesus
Creators: name: Wei, Lianmeng
name: Zhang, Lili
Publisher: name: Zenodo
Year: 2010
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Dolichopodidae
Chrysotus
Chrysotus laesus

description: Key to species of the Chrysotus laesus -group
1 Male epandrium with characteristic angular projection posteriorly. Hypandrium with process at apex. Postocular and occiput with setae usually black. Proboscis and palpus usually blackish brown or brownish black, seldom yellowish. Legs with femora usually brownish black or black, at most individual species yellowish at tip, with tibiae always
more or less yellowish; sometimes with coxae and femora dark metallic green ............. Chrysotus laesus -group ... 2 - Male epandrium without characteristic angular projection posteriorly at most arc projection posteriorly; other features variable .................................................................................................................................. other species-groups
2 Male eyes separated widely on face ............................................................................................................................ 3
- Male eyes contiguous, at most narrowly separated on face......................................................................................... 6
3 Postocular and occiput with setae pale. Face long trapezoidal, the narrowest lower portion about as wide as first flagellomere. Antennae with first flagellomere short, nearly rectangular, at most 0.5 as long as width. Femora black, usually yellow apically (but C. laesus with femora wholly black); mid tibia without setae (MSSC). Fore coxa with pale setulae and setae anteriorly. Male terminalia: ventral projection of epandrium with end flat; lateral epandrial lobe is triangular; surstylus flattened distally; hypandrium stout, apical part swollen and rounded apically ............ 4
- Postocular and occiput with setae black. Face “X-shaped” the narrowest portion at below middle, which is about as wide as width of tarsomere 5. Male mid tibia with 3 ad and 1 ventral seta. Fore coxa with black setulae and setae anteriorly. Male terminalia with other features variable ................................................................ laxifacialus sp. nov.
4 Both femora and tibiae black. Fore coxa with pale setae anteriorly and tarsus with pale setulae. Male terminalia (Negrobov 1980, fig. 7): cercus longer than broad and narrow apically .................................... laesus (Wiedemman)
- Femora black, but at least fore and mid femora yellow apically. Tibiae more or less yellow. Fore coxa with pale setae anteriorly or antero-apically and tarsus with setulae black. Male terminalia: cercus longer or shorter than broad but wider apically ............................................................................................................................................................... 5
5 Fore and mid femora yellow apically. Fore coxa with pale setae antero-apically. Male terminalia (Wang & Yang 2006, fig. 8): cercus shorter than broad, nearly round; lateral epandrial lobe with end tongue-shaped; hypandrium with enlarged apical part in an open loop ................................................................................. serratus Wang & Yang
- Femora wholly yellow apically. Fore coxa with pale setae anteriorly. Male terminalia (Fig. 9 A): cercus longer, oval; lateral epandrial lobe equilateral triangle in shape; hypandrium with enlarged apical part in a closed loop ................. ............................................................................................................................................................ pallidus sp. nov.
6 Male eyes narrowly separated on face. Fore and mid femora chiefly black with dark yellow tip ................................. .............................................................................................................................................. brevicercus Wang et Yang
- Male eyes contiguous on face. Femora entirely black.................................................................................................. 7
7 First flagellomere triangular, 1.3 times as long as wide. Femora with two rows of long ventral setae. Halter brown. ............................................................................................................................................ guizhouensis Wang & Yang
- First flagellomere subtriangular, with length shorter than width. Femora without row of long ventral setae. Halter pale................................................................................................................................................................................ 8
8 Palpus yellow or brown; proboscis brown................................................................................................................... 9
- Palpus and proboscis black or blackish brown .......................................................................................................... 13
9 Postocular setae pale; dc 5. Squama with blackish brown setulae ............................................. fanjinshanus sp. nov.
- Postocular setae black; dc 6. Squama with black or brown setulae............................................................................ 10
10 Palpus brownish yellow. Male terminalia (Fig. 3): end of ventral projection of epandrium with acute anterior angle and hook-like posterior angle; in which the former not beyond the level of flat distal margin of lateral epandrial lobe; proximal portion of hypandrium with low flat process..................................................................... anshunus sp. nov.
- Palpus brown. Male terminalia variable ..................................................................................................................... 11
11 Squama with black setulae. Male terminalia (Fig. 1): surstylus almost straight (only base and pointed apex bent) and hypandrium with banana-shaped dorsolateral projection; proximal portion of hypandrium with one small finger-like processes ............................................................................................................................................ adunatus sp. nov.
- Squama with brown setulae. Male terminalia: surstylus curved, never straight at midlength and hypandrium variable .................................................................................................................................................................................... 12
12 Femora brown, without dark metallic green, hind tibia with 3 pd. Male terminalia (Fig. 7): ventral projection of the epandrium small and narrow, with end acute anteriorly; proximal portion of hypandrium with two projections ........ ........................................................................................................................................................ fuscitibialis sp. nov.
- Femora brownish black, with dark metallic green, hind tibia with 5 pd. Male terminalia (Fig. 2): ventral projection of the epandrium very large and wide, with end flat; proximal portion of hypandrium seldom with projection........... ............................................................................................................................................................ agraulus sp. nov.
13 Femora brown, without metallic green shine, hind tibia with 3 pd. Male terminalia (Fig. 5 A): hypandrium thick and strong, with a pair of apically rounded lateral projections near apex .......................................... biprojicienus sp. nov.
- Femora blackish brown or black, with metallic green shine, hind tibia with 4 to 7 pd. Male terminalia: hypandrium with a ventral projection near apex ............................................................................................................................. 14
14 Femora black. Male terminalia (Fig. 10 A): end of ventral projection of epandrium beyond apical margin of lateral epandrial lobe................................................................................................................................... trapezinus sp. nov.
- Femora blackish brown. Male terminalia: end of ventral projection of epandrium not beyond apical margin of lateral epandrial lobe............................................................................................................................................................. 15
15 Male terminalia (Fig. 4): epandrium markedly recurved; lateral epandrial lobe shorter and wider; surstylus slender
with narrow base, only slightly wider than apex; hypandrium with ventral projection pointed apically ...................... .................................................................................................................................................... apicicaudatus sp. nov. - Male terminalia (Fig. 11 A): epandrium slightly recurved; lateral epandrial lobe longer and narrower; surstylus thick and strong, with wider base; hypandrium with ventral projection rounded apically........................... xinanus sp. nov.
description: Published as part of 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, pp. 1-22 in Zootaxa 2683 on pages 3-5, DOI: 10.5281/zenodo.199386