Key to the species of the genus Troglocollops Wittmer, 1965

(males only)

1. Pronotum uniformly dark; antennomeres 1 and 3 feebly enlarged ( Troglocollops ( Troglocollops))..................... 2

- Pronotum mixed yellow and black; antennomeres 1 and 3 distinctly swollen...................................... 8

2. Elytra dark, with yellow spots at the middle of suture, outer edge and apex.............. T. bituberculatus Wittmer, 1979

- Elytra uniformly dark.................................................................................. 3

3. Interocular area of head flat, with small ribs or protuberances.................................................. 4

- Interocular area of head distinctly impressed or hollowed..................................................... 5

4. Pronotum longitudinal; interocular area of head with two narrow transversal ribs (one in the midspan between eyes, the other in the distal part).............................................................. T. wittmeri Tshernyshev, 1995

- Pronotum transversal; interocular area of head with a short transversal crown-shaped protuberance in the middle....................................................................................... T. coronatus Wittmer, 1992

5. Frons with a deep transverse hollow.......................................... T. mordkovitshi Tshernyshev, 1994

- Frons or interocular area of head without transversal hollow................................................... 6

6. Dorsal surface of pronotum and elytra wrinkled; head with two longitudinal depressions, forming a peculiar median rib...................................................................................... T. niger Wittmer, 1992 - Dorsal surface of pronotum and elytra shagreened; head with one depression or crest............................... 7

7. Interocular area of head with a deep, rounded depression............................ T. sundukovi Tshernyshev, 1994

- Interocular area of head with a long and simple longitudinal crest, forming a little horn.................................................................................................... T. obscuricornis (Motschulsky, 1860)

8. Antennomere 3 prolonged and slightly impressed, distinctly smaller than 1 ( Troglocollops (Alexeus))................... 8

- Antennomere 3 impressed with outer edge slightly curved inwards, feebly larger than 1 ( Troglocollops (Troglocollopsoides)) .................................................................................................. 11

8. Pronotum dark with narrow yellow edges.................................................................. 9

- Pronotum dark with wide yellow edges................................................................... 10

9. Interocular area of head yellow with a little dark spot; antennae with a little dark spot at apex.................................................................................................. T. tshemerisi Tshernyshev, 1994

- Interocular area of head yellow with a wide longitudinal dark spot; antennae entirely yellow.. T. mongolicus Wittmer, 1965

10. Sculpture of frons with two emarginations, median bristles black; antennomere 1 roundish.. T. logunovi Tshernyshev, 1994

- Sculpture of frons with one emargination, median bristles brown; antennomere 1 sharpened apically.................................................................................................. T. dlabolai Wittmer, 1968

11. Pronotum yellow with a black median longitudinal stripe reaching anterior and posterior edges; elytra dark with yellow apices; antennae yellow with a small black spot at apex................................... T. sinicus Tong & Yang, sp. nov.

- Pronotum and elytra dark with yellow edges; antennae yellow basally with antennomeres 6–11 entirely black........... 12

12. Interocular area of head flat, with small protuberances..................................... T. kaszabi (Evers, 1965)

- Interocular area of head hollowed or depressed............................................................ 13

13. Interocular area of head with a deep transversal hollow above eyes.......................... T. cinctus (Gebler, 1847)

- Interocular area of head with a round depression between eyes................................................ 14

14. Interocular depression wide and mostly black; elytra with narrow yellow edges...... T. latecavus latecavus Wittmer, 1969

- Interocular depression mixed black and yellow; elytra with wide yellow edges................................... 15

15. Interocular area of head black with yellow ribs of depression................... T. latecavus medvedevi Wittmer, 1979

- Interocular area of head with a narrow longitudinal dark spot.............. T. latecavus urianchaicus Tshernyshev, 1994