Key to species of the genus Oncopsis from China (males)
1. Face as wide as long, tegmina with 2 anteapical cells (subgenus Parasitades)................................ O. fusca
- Face narrower than long, tegmina with 3 anteapical cells (subgenus Oncopsis)..................................... 2
2. Dorsal connective without bifurcated processes.............................................................. 3
- Dorsal connective with bifurcated processes................................................................ 5
3. Processes of dorsal connective short and slender................................................... O. aurantiaca
- Processes of dorsal connective long and wide............................................................... 4
4. Processes of dorsal connective with serrated ventral margin......................................... O. cuneiforma
- Processes of dorsal connective without serrated ventral margin........................................ O. flavovirens
5. Dorsal connective processes with a short and degraded shaft................................................... 6
- Dorsal connective processes with a long and obvious shaft.................................................... 12
6. Branches of dorsal connective processes not obviously separated........................................ O. testacea
- Branches of dorsal connective processes clearly separated..................................................... 7
7. Upper branch of dorsal connective process shorter than other one................................................ 8
- Upper branch of dorsal connective process longer than other one............................................... 10
8. One dorsal connective branch reduced, without serrated inner margin................................. O. odontoidea
- Both branches slender, with serrated inner margin............................................................ 9
9. Aedeagus shaft tapering from base to apex in ventral view, apex blunt................................... O. melichari
- Aedeagus shaft with parallel margins in ventral view, apex with distinct dent......................... O. kangdingensis
10. S-shaped dorsal connective separated from the upper process branch..................................... O. fumosa
- S-shaped dorsal connective crossed from the upper process branch.............................................. 11
11. Dorsal connective large, both branches long, basally slender........................................... O. kuluensis
- Dorsal connective relatively small, both branches short, basally wide....................................... O. tristis
12. Branches of dorsal connective processes relatively short...................................................... 13
- Branches of dorsal connective processes long.............................................................. 14
13. Face largely black, remaining area light yellowish................................................. O. nigrofaciala
- Face yellow, with wide black transverse band, clypellus black......................................... O. serrulota
14. Upper branch clearly shorter than lower one, tip sharpened............................................ O. obstructa
- Upper branch longer than lower one, tip blunt.............................................................. 15
15. Both branches of dorsal connective with serrated inner margin................................................. 16
- One or neither branch with serrated inner margin............................................................ 19
16. Body black, style with blunt end........................................................... O. latusoid sp. nov.
- Body brown, style with normal end...................................................................... 17
17. Black transverse band between eyes not concave, frontoclypeus brown............................... O. nigrofaciatus
- Black transverse band between eyes concave at lower margin, frontoclypeus black................................. 18
18. Style tip without additional spine, connective of usual width........................................... O. convexus
- Style tip sharpened with additional spine, connective moderately slender.................................. O. spinosa
19. Both branches without serrated inner margin............................................................... 20
- One branch with serrated inner margin.................................................................... 21
20. Median aedeagal shaft not inflated.............................................................. O. anchorous
- Median aedeagal shaft slightly inflated............................................................... O. furca
21. Upper branch of dorsal connective with serrated outer margin, tips sharpened..................... O. taibaiensis sp. nov.
- Upper branch without serrated outer margin, tips blunt................................................... O. alni