Key to species (males) of Drabescus from China

( D. albostriatus, D. atratus, D. extensus, D. fuscorufous, D. notatus and D. piceus omitted).

1. Pygofer side without processes and with apex broadly rounded................................................. 2

- Pygofer side with processes or apex narrow and attenuate..................................................... 10

2. Aedeagal shaft with pair of processes basally................................................................ 3

- Aedeagal shaft with pair of processes medially (Figs. 1)............................................... D. peltatus

3. Aedeagal shaft with branched basal processes............................................................... 4

- Aedeagal shaft basal processes unbranched.................................................................8

4. Basal processes each with at least two branches (Figs. 2)............................................ D. jinxiuensis

- Basal processes each with one branch...................................................................... 5

5. Aedeagal shaft expanded subapically...................................................................... 6

- Aedeagal shaft not expanded subapically...................................................................7

6. Valve triangular, subgenital plate slender (Figs. 3–4).................................................. D. furcatus

- Valve arcuate, subgenital plate slightly broadened (Figs. 5–6)......................................... D. lamellatus

7. Aedeagal shaft cylindricall (Figs. 7).................................................................... D. lii

- Aedeagal shaft short spiniform (Figs. 8)............................................................ D. gracilis

8. Connective Y-shaped................................................................................... 9

- Connective U-shaped (Figs. 9–10).............................................................. D. pellucidus

9. Basal processes of aedeagal shaft with evenly curved lateral margins (Figs. 11)............................. D. piceatus

- Basal processes of aedeagal shaft with sinuate lateral margins (Figs. 12)................................. D. minipenis

10. Pygofer side with evenly curved sinuate process............................................................ 11

- Pygofer side with tapering apex or straight process.......................................................... 13

11. Aedeagal shaft with pair of basal processes, longer than shaft (Figs. 13)............................... D. formosanus

- Processes not as above................................................................................ 12

12. Aedeagal shaft in lateral view narrowed from base to apex (Figs. 14).................................... D. ineffectus

- Aedeagal shaft in lateral view with ventral margin expanded medially (Figs. 15).......................... D. henanensis

13. Aedeagus with process................................................................................ 14

- Aedeagus without process (Figs. 16)..................................................... D. cuspidatus sp. nov.

14. Aedeagus with two pairs of processes (Figs. 17)............................................... D. quadrispinosus

- Aedeagus with pair of processes......................................................................... 15

15. Aedeagus with a pair of medial processes................................................................. 16

- Aedeagus with pair of basal processes.................................................................... 17

16. Aedeagus basal processes slightly shorter than shaft (Figs. 18)......................................... D. testaceus

- Aedeagus basal processes very short (Figs. 19)................................................... D. conspicuous

17. Aedeagus basal processes extending to near apex of shaft..................................................... 18

- Aedeagus basal processes extending to midlength of shaft....................................................21

18. Aedeagal shaft with expanded distal part (Figs. 20)................................................. D. albosignus

- Aedeagal shaft with narrowed distal part.................................................................. 19

19. Aedeagal shaft compressed, with broad basal processes (Figs. 21)................................ D. nervosopunctatus

- Aedeagal shaft columnar, with slender basal processes....................................................... 20

20. Aedeagal shaft apex acute ventrally (Figs. 22)........................................... D. multidentatus sp. nov.

- Aedeagal shaft apex round ventrally (Figs. 23)..................................................... D. vilbastei

21. Pygofer side with serrate margin ventrally (Figs. 24).................................................. D. ogumae

- Pygofer side with smooth margin ventrally................................................................ 22

22. Aedeagal shaft in lateral aspect columnar and straight (Figs. 25).................................... D. shillongensis

- Aedeagal shaft in lateral aspect sinuate.................................................................... 23

23. Connective stem twice as long as arms (Figs. 26–27)........................................ D. convolutus sp. nov.

- Connective stem similar in length to arms (Figs. 28–29)................................................ D. nitobei