Polypedilum (Tripodura) Townes

Zhang, Ruilei, Song, Chao, Qi, Xin & Wang, Xinhua, 2016, Taxonomic review on the subgenus Tripodura Townes (Diptera: Chironomidae: Polypedilum) from China with eleven new species and a supplementary world checklist, Zootaxa 4136 (1), pp. 1-53 : 38-39

Key to male imagines of Polypedilum (Tripodura) Townes from China

1. Tergite IX without lateral projections or shoulders............................................................ 2

- Tergite IX with lateral projections or conspicuous shoulders.................................................... 9

2. Anal point elongation extremely reduced.................................. P. (T.) conghuaense Zhang & Wang sp. n.

- Anal point elongation normal............................................................................ 3

3. Anal point slender and nearly parallel-sided................................................................. 4

- Anal point broad or apically expanded..................................................................... 5

4. AR 0.80, terminal scale of front tibia oval and apically rounded, superior volsella with 3–5 long apical setae............................................................................................. P. (T.) masudai (Tokunaga)

- AR 1.32–1.66, terminal scale of front tibia triangular and apically pointed, superior volsella with 2 long apical setae...................................................................................... P. (T.) udominutum Niitsuma

5. Wing without markings, anal lobe reduced............................... P. (T.) absensilobum Zhang & Wang sp. n.

- Wing with markings, anal lobe normal..................................................................... 6

6. Superior volsella spatulated and inferior volsella with less than 5 setae............................... P. (T.) spathum Zhang & Wang

- Superior volsella pad-like and inferior volsella with more than 10 setae........................................... 7

7. Terminal scale of fore tibia pointed, distal margin of superior volsella with 2–3 setae, anal point broad, distal part of r4+5 clear................................................................................................................................. P. (T.) japonicum (Tokunaga)

- Terminal scale of fore tibia rounded, distal margin of superior volsella with more than 19 setae, anal point spatula-shaped api- cally, distal part of r4+5 cloudy............................................................................ 8

8. Anal point with 6 setae at base, superior volsella goblet-shaped; gonostylus slender and apex narrowed...................................................................................................................................... P. (T.) cypellum Qi et al.

- Anal point with 2 rows of short setae on dorsal lamella, each row with 8−10 setae; superior volsella pediform; gonostylus moderately broad, apex not narrowed...................................................................... P. (T.) harteni Andersen & Mendes

9. Anal point slender and almost parallel-sided, spot in cell m1+2 proximal to spot in cell r4+5........ P. (T.) unifascia (Tokunaga)

- Anal point broad or apically expanded, spot in cell m1+2 not proximal to spot in cell r4+5 or wing without marking........ 10

10. Wing without markings, superior volsella slender and S-shaped.......................... P. (T.) procerum Zhang et al.

- Wing with markings, usually boldly marked with several dark spots and clouds, sometimes faint and restricted to a few areas; superior volsella not S-shaped........................................................................... 11

11. Wing with 0–1 spot in cell r4+5.......................................................................... 12

- Wing with 2–3 spots in cell r4+5......................................................................... 17

12. Wing marking faint, without spot in cell r4+5, superior volsella sickle-shaped.......................... P. (T.) falcatum Zhang et al.

- Wing with 1 spot in cell r4+5, superior volsella not sickle-shaped................................................ 13

13. Fore tibial scale rounded apically.................................................... P. (T.) scalaenum (Schrank)

- Fore tibial scale pointed apically........................................................................ 14

14. Lateral projections of anal point strongly sclerotized and without microtrichia, the superior volsella clavate............................................................................... P. (T.) nudiprostatum Zhang, Wang & Saether

- Lateral projections of anal point covered with microtrichiae, the superior volsella trapezium-shaped or pad-like......... 15

15. The superior volsella trapezium-shaped, wing cloudy on distal margin............. P. (T.) trapezium Zhang & Wang sp. n.

- The superior volsella pad-like, wing clear on distal margin.................................................... 16

16. Gonostylus slender and parallel-sided basal 1/4, lateral projection of anal point slender, marking in cell m1+2 long and opposite to marking in cell r4+5.................................................... P. (T.) parallelum Zhang & Wang sp. n.

- Gonostylus not as above, lateral projection of anal point broad, marking in cell m1+2 long and distal to marking in cell r4+5................................................................................. P. (T.) quadriguttatum Kieffer

17. Wing with 3 dark spots in cell r4+5...................................................................... 18

- Wing with 2 dark spots in cell r4+5........................................................................ 19

18. AR 1.80–1.95, superior volsella pad-like...................................... P. (T.) decematoguttatum (Tokunaga)

- AR 0.70–0.75, superior volsella clavate.................................. P. (T.) mengmanense Zhang & Wang sp. n.

19. Setae on vein R4+5 less than 7 and situated distal 1/3 to apex................. P. (T.) apiculusetosum Zhang & Wang sp. n.

- Setae on vein R4+5 more than 15 and situated from basal 1/4 to apex............................................ 20

20. Superior volsella clavate.............................................................................. 21

- Superior volsella pad-like.............................................................................. 22

21. Superior volsella toe-like, narrowed in the middle, covered with microtrichia and with 3 apical setae........................................................................................... P. (T.) pollicium Zhang & Wang sp. n.

- Superior volsella slightly curved and gradually tapering to apex, with 2 strong spines directed inwards in middle and 1 outer sub-apical setae.............................................................. P. (T.) bispinum Zhang & Wang

22. AR more than 1.10, the superior volsella with 6–7 apical setae....................... P. (T.) cochlearum Zhang & Wang

- AR less than 0.80, the superior volsella with 1–3 apical setae................................................. 23

23. The gonostylus expanded in the middle and bent like a bow...................... P. (T.) arcuatum Zhang & Wang sp. n.

- The gonostylus not expanded in the middle................................................................ 24

24. The spots in cell m1+2 dark and cloudy on wing distal margin..................... P. (T.) bilamella Zhang & Wang sp. n.

- The spots in cell m1+2 faint and clear on wing distal margin.................................................... 25

25. AR 0.61. Superior volsella with 2 long apical setae. Anal point with transparent lobes in middle part........................................................................................ P. (T.) napahaiense Zhang & Wang sp. n.

- AR 0.28-0.40. Superior volsella with 1 long apical seta. Anal point lanceolate, without transport transparent lobe in middle part....................................................................... P. (T.) dengae Zhang & Wang sp. n.