Chrysotimus taiwanensis, Wang & Chen & Yang, 2015

Wang, Mengqing, Chen, Hongyin & Yang, Ding, 2015, New and little known species of Dolichopodidae (Diptera) in Taiwan, Florida Entomologist 98 (2), pp. 752-752 : 752-

Key to species (males) of Chrysotimus from China

1. — Hind tarsomere 1 at most with sparse black bristles at base.............................................................. 2

1’.— Hind tarsomere 1 with bundle(s) of black ventral bristles at base......................................................... 10 2 (1). Hind tarsomere 1 without black ventral bristles at base (unknown in C. grandis )............................................. 3

2’.— Hind tarsomere 1 with black ventral bristles at base..................................................................... 6 3 (2). Acr present...................................................................................................... 4

3’.— Acr absent....................................................................................................... 5 4 (3). Mid tarsomere 1 shorter than tarsomeres 2–5; surstylus with single lobe..................... C. beijingensis ( Yang & Saigusa, 2001)

4’.— Mid tarsomere 1 longer than tarsomeres 2–5; surstylus divided into 2 lobes........................ C. grandis Wang & Yang, 2006 5 (3). Mid tibia with 2 pd; epandrium process nearly quadrate.................................. C. guangxiensis Yang & Saigusa, 2001

5’.— Mid tibia with 1 pd; epandrium process with apical concavity.......................................... C. sinensis Parent, 1944 6 (2). Antenna with 1st and 2nd antennal segments yellow................................................. C. basiflavus Yang, 2001

6’.— Antenna wholly black............................................................................................. 7 7 (6). Five dc; acr absent.......................................................................... C. apicicurvatus Yang, 2001

7’.— Six dc; acr present................................................................................................. 8

8 (7). Nine to 10 irregularly paired acr; hind tarsomere 1 with 2 sparse black ventral bristles at base..................................

........................................................................... C. ningxianus Wang, Yang & Grootaert, 2005

8’.— Less than 6 irregularly paired acr; hind tarsomere 1 with 6–8 sparse black ventral bristles on basal 1/4.......................... 9 9 (8). Hind tibia with 2 ad, epandrium with long wide and trifurcated lateral process............. C. dalongensis Wang, Chen & Yang, 2012

9’.— Hind tibia with 1 ad, epandrium with short and bifurcated lateral process............... C. acutatus Wang, Yang & Grootaert, 2005 10 (1). Four or 5 dc; acr absent........................................................................................... 11

10’.— Six dc; acr present................................................................................................ 18 11(10). Arista dorsal; hypandrium with broad lateral process................................................................... 12

11’.— Arista sub-apical; hypandrium with thin finger-like lateral process........................................................ 13 12(11). Hind tibia with row of v, surstylus wide............................................................... C. dorsalis Yang, 2001

12’.— Hind tibia without rowed v, surstylus slender........................................ C. huairouensis Wang, Chen & Yang, 2012 13(11). Hind tarsomere 1 with 3–4 short black spine-like ventral bristles at base............... C. songshanus Wang, Yang & Grootaert, 2005

13’.— Hind tarsomere 1 with more than 5 black ventral bristles at base......................................................... 14

14(13). Hairs and bristles on thorax yellow.................................................................................. 15

14’.— Hairs and bristles on thorax brownish or brown....................................................................... 16

15(14). Fore tarsomere 1 with row of about 10 v; hind tarsomere 1 with 22 short black ventral bristles on basal 1/4; surstylus basally without inner process.................................................................... C. chikuni Wang, Yang & Grootaert, 2005

15’.— Fore tarsomere 1 without rowed v; hind tarsomere 1 with less than 20 black ventral bristles on basal 1/4; surstylus basally with inner process......................................................................... C. shennongjianus Yang & Saigusa, 2001

16(14). Hind tarsomere 1 with row of v; surstylus furcated apically.............................................................. 17

16’.— Hind tarsomere 1 without rowed v; surstylus not furcated apically............................... C. bispinus Yang & Saigusa, 2001

17(16). Hind tarsomere 1 with 15–16 black basal ventral bristles; cercus round...................... C. xuae Wang, Yang & Grootaert, 2005

17’.— Hind tarsomere 1 with 7–8 black basal ventral bristles; cercus with acute apex............................ C. taiwanensis sp. nov.

18(10). Acr 2–4 pairs.................................................................................................... 19

18’.— Acr 5 or more pairs............................................................................................... 26

19(18). Hind tarsomere 1 with group of 8–12 black ventral bristles at base (which are somewhat sparse), but without distinct pv.......... 20

19’.— Hind tarsomere 1 with 1 (or 2) bundles of black basal ventral bristles, and row of 7–8 pv..................................... 22

20(19). CuAx ratio about 0.2; lateral process on epandrium not concave near middle............................................... 21

20’.— CuAx ratio 0.35; lateral process on epandrium concave near middle.......................... C. yunlonganus Yang & Saigusa, 2001

21(20). First flagellomere as long as wide; hind tibia without distinct v......................................... C. lii Wang & Yang, 2006

21’.— First flagellomere about 1.5 times wider than long; hind tibia with 2 pv.......................... C. linzhiensis Wang & Yang, 2006

22(19). R 4+5 and M parallel apically; hind tarsomere 1 with bundle of 4–5 black ventral bristles at base................................ 23

22’.— R 4+5 and M slightly convergent apically; hind tarsomere 1 with 2 bundles of 3–4 black ventral bristles at base............................................................................................................ C. bifascia Yang & Saigusa, 2005

23(22). Hairs and bristles on thorax yellow or pale; surstylus on epandrium not furcated apically..................................... 24

23’.— Hairs and bristles on thorax brown; surstylus on epandrium furcated apically........ C. sanjiangyuanus Wang, Yang & Grootaert, 2005

24(23). Fore tarsomere 1 without rowed v; hind tarsomere 1 with 4–5 black ventral bristles at base.................................. 25

24’.— Fore tarsomere 1 with row of 5–6 v; hind tarsomere 1 with 8 black ventral bristles at base............................................................................................................. C. guangdongensis Wang, Yang & Grootaert, 2005

25(24). Hind femur with row of ad and pd; cercus long and narrow..................... C. xiaolongmensis Zhang, Yang & Grootaert, 2003

25’.— Hind femur without distinct d; cercus round................................................ C. unifascia Yang & Saigusa, 2005

26(18). Hind tarsomere 1 with row of about 10 pv............................................................................ 27

26’.— Hind tarsomere 1 without distinct v................................................................................. 30

27(26). Hind tarsomere 1 with 10–12 black ventral bristles at base; mid tibia without distinct v....................................... 28

27’.— Hind tarsomere 1 with about 20 black ventral bristles at base; mid tibia with 1 pv........................................... 29

28(27). First flagellomere somewhat round, 2.0 times wider than long; cercus not furcated; dorsal lobe on surstylus thick and straight........................................................................................... C. qinlingensis Yang & Saigusa, 2005

28’.— First flagellomere subtriangular, about as long as wide; cercus bifurcated; dorsal lobe on surstylus thin and curved....................................................................................................... C. bifurcatus Wang & Yang, 2006

29(27). Fore and mid tarsomere 1 without distinct v; epandrium basally with short process................ C. setosus Yang & Saigusa, 2005

29’.— Fore and mid tarsomere 1 each with row of 5–6 v; epandrium basally with long and broad process...................................................................................................... C. xiaohuangshanus Wang, Yang & Grootaert, 2005 30(26). Hind tarsomere 1 with bundle of short black ventral bristles; surstylus rather wide and thick; hypandrium with small apical incision................................................................................................................. 31

30’.— Hind tarsomere 1 with 2–3 bundles of 14–15 black ventral bristles on basal 1/6; surstylus narrow finger-like; hypandrium without apical incision............................................................................... C. digitatus Yang & Saigusa, 2001

31(30). Hairs and bristles on thorax pale or yellow............................................................................ 32

31’.— Hairs and bristles on thorax dark brown; hind tarsomere 1 with 15–16 black ventral bristles....... C. pingbianus Yang & Saigusa, 2001

32(31). Hind tarsomere 1 with 7 or less short black ventral bristles; 6 irregularly paired acr; palpus yellow............................. 33

32’.— Hind tarsomere 1 with 12 short black ventral bristles; 8 irregularly paired acr; palpusdark brown....... C. incisus Yang & Saigusa, 2001

33(32). Hind tibia with 2 pd, hind tarsomere 1 with 4–5 short black ventral bristles; surstylus slender and finger like...................................................................................................... C. hubeiensis Wang, Chen & Yang, 2012

33’.— Hind tibia with 1 pd, hind tarsomere 1 with 7–8 short black ventral bristles; surstylus very wide.... C. lijianganus Yang & Saigusa, 2001