Triomicrus

Key to the males of Triomicrus of China

1 Elytral subhumeral sulcus present........................................................................ 2

- Elytral subhumeral sulcus absent....................................................................... 20

2 Elytral subhumeral sulcus short, barely reaching half of elytral length........................................... 3

- Elytral subhumeral sulcus long, reaching level of posterior edge of metacoxa.................................... 11

3 Head with median vertexal carina. (Guangdong)....................................... T. nanlingensis Shen & Yin

- Head lacking median vertexal carina..................................................................... 4

4 Protibia with apical spur or protuberance................................................................. 5

- Protibia lacking apical spur nor protuberance.............................................................. 7

5 Antennomere XI lacking protuberance; protrochanter with an acute basal denticle, protibia with acute apical denticle, mesotibia with acute apical lamina. (Taiwan)................................ T. onerosus Löbl, Kurbatov & Nomura

- Antennomere XI with protuberance...................................................................... 6

6 Protibia with triangular apical spur; antennomere XI with impression near middle; apical lamina of abdominal sternite VII strongly transverse, pointed at apex of lateral margin. (Jiangxi)................................ T. hamus Shen & Yin

- Protibia with long and rounded apical protuberance; apical lamina of abdominal sternite VII slender, narrowed at base and pointed at apex. (Zhejiang and Fujian)................................... T. rougemonti Löbl, Kurbatov & Nomura

7 Antennomere X distinctly longer than wide; apical lamina of abdominal sternite VII narrowed near base and pointed at apex. (Zhejiang)....................................................................... T. frondosus Shen & Yin

- Antennomere X almost as long as wide, or distinctly wider than long........................................... 8

8 Antennomere X almost as long as wide. (Hunan)......................................... T. mangshanensis sp. n.

- Antennomere X distinctly wider than long................................................................ 9

9 Metaventrite with pair of protuberances lacking setal tuft. (Taiwan)............... T. secutor Löbl, Kurbatov & Nomura

- Metaventrite with pair of protuberances bearing tufted of seta................................................ 10

10 Metaventrite with setal tufts oriented apically. (Taiwan)........................ T. factitatus Löbl, Kurbatov & Nomura

- Metaventrite with setal tufts oriented ventro-anteriorly. (Taiwan)................. T. adnexus Löbl, Kurbatov & Nomura

11 Head with median vertexal carina...................................................................... 12

- Head lacking median vertexal carina.................................................................... 13

12 Pronotum entirely covered with dense and coarse punctuation. (Zhejiang)................... T. abhorridus Shen & Yin

- Pronotum partially, finely and sparsely punctate; apical lamina of abdominal sternite VII short, with rounded apex. (Zhejiang).............................................................................. T. damingensis Shen & Yin

13 Protrochanter with long spine. (Anhui)................................................ T. inaequalis Shen & Yin

- Protrochanter lacking spine........................................................................... 14

14 Profemora distinctly enlarged......................................................................... 15

- Profemora normal................................................................................... 16

15 Diameter of protuberance of antennomere XI about half of segmental length; apical lamina of abdominal sternite VII com- posed of two sclerites, each curved mesally. (Guangxi)...................................... T. longus Shen & Yin

- Diameter of protuberance of antennomere XI about one-sixth of segmental length; abdominal sternite VII with apical lamina composed of two complicated sclerites, left one curved mesally, widest near base, obliquely narrowing toward bifurcate apex, with a tiny horn-like projection at middle, right one elongate, curved mesally at apex (Fig. 6 D). (Anhui, Hunan)............................................................................................... T. mirus Shen & Yin

16 Mesotibia lacking apical spur. (Sichuan)................................... T. ludificator Löbl, Kurbatov & Nomura

- Mesotibia with apical spur............................................................................ 17

17 Protibia with an apical spur. (Chongqing, Sichuan, Shaanxi).................. T. punctifrons Löbl, Kurbatov & Nomura

- Protibia lacking apical spur........................................................................... 18

18 Abdominal tergite IV lacking basal carina. (Zhejiang)......................................... T. humilis Raffray

- Abdominal tergite IV with basal carinae................................................................. 19

19 Mesotibia with triangular preapical marginal projection; antennomere XI with strongly prominent protuberance; apical lamina of abdominal sternite VII transverse, strongly curved and pointed at apex. (Zhejiang).............. T. tibialis Shen & Yin

- Mesotibia with small apical denticle. (Zhejiang)........................................... T. cavernosus Raffray

20 Head with median vertexal carina...................................................................... 21

- Head lacking median vertexal carina.................................................................... 22

21 Head entirely densely punctate. (Sichuan)...................................... T. algon Löbl, Kurbatov & Nomura

- Head finely and sparsely punctate; apical lamina of abdominal sternite VII narrowed near base, widest near middle, posterior margin obliquely narrowed. (Guangxi).................................................... T. cavus Shen & Yin

22 Mesotibia with apical spine........................................................................... 23

- Mesotibia lacking apical spine......................................................................... 24

23 Mesotibia with small apical denticle; antennomere XI lacking protuberance; apical lamina of abdominal sternite VII stout, widest near middle, posterior margin obliquely narrowed. (Zhejiang)....................... T. gutianensis Shen & Yin

- Mesotibia with long apical spine; pronotum entirely, densely and coarsely punctate; apical lamina of abdominal sternite VII narrowed near base, widest at apex. (Guangdong, Guangxi)................................... T. cochlis Shen & Yin

24 Protibia with long apical spine......................................................................... 25

- Protibia lacking apical spine.......................................................................... 26

25 Protibia with long apical spine, protarsomere I lacking spine; pronotum entirely, densely and coarsely punctate; apical lamina of abdominal sternite VII transverse, rounded at apex of lateral margin. (Guangdong).............. T. acutus Shen & Yin

- Protibia with long apical spine, protarsomere I with three minute spines; apical lamina of sternite VII comprises two sclerites, with the left apical margin strongly elongate. (Yunnan)...................................... T. nabanhensis sp. n.

26 Pronotum entirely covered with dense and coarse punctuation. (Hunan, Guangdong)............ T. pinnatus Shen & Yin

- Pronotum partially, finely and sparsely punctate........................................................... 27

27 Antennomere XI lacking rounded impression. (Zhejiang, Anhui)............................ T. anfractus Shen & Yin

- Antennomere XI with distinct rounded impression......................................................... 28

28 Antennomere XI with rounded impression surrounding slightly prominent disc-like protuberance near base; apical lamina of abdominal sternite VII broadest near middle and arcuate toward apex. (Zhejiang, Jiangxi)........... T. contus Shen & Yin

- Antennomere XI with rounded impression surrounding strongly prominent disc-like protuberance near base; apical lamina of abdominal sternite VII slender, apex slightly curved laterally. (Zhejiang)....................... T. aculeus Shen & Yin