Key to genera of Tropidocephalini Muir, 1915 from China

(Modified from Qin & Zhang, 2010)

1. Body strongly flattened (Figs 1B, 3B, 5B) ........................................ Aodingus Chen & Li gen. nov.

– Body not flattened ............................................................................................................................. 2

2. Vertex subtriangular .......................................................................................................................... 3

– Vertex quadrate or nearly so ............................................................................................................. 4

3. Vertex raised upwards at apex; frons in midline more than 3.0 × as wide as maximum width .......... ....................................................................................................................... Conocraera Muir, 1916

– Vertex not raised upwards at apex; frons in midline less than 3.0 × as wide as maximum width ...... .................................................................................................................. Tropidocephala Stål, 1853

4. Antennal segment I distinctly large and flattened, longer than segment II .... Purohita Distant, 1906

– Antennal segment I not as above, if flattened, then shorter than segment II .................................... 5

5. Antennal segment I sagittate or strongly widening towards apex .................................................... 6

– Antennal segment I not sagittate or strongly widening towards apex .............................................. 7

6. Antennal segment I with median longitudinal carina .................... Neobelocera Ding & Yang, 1986

– Antennal segment I without median longitudinal carina ................................... Belocera Muir, 1913

7. Frons in front of vertex acutely convex in dorsal aspect, in profile apex of frons strongly bent caudad ................................................................................................. Arcifrons Ding & Yang, 1986

– Frons not as above ............................................................................................................................ 8

8. Postclypeus in profile strongly bent at right angle to frons .............................................................. 9

– Postclypeus in profile in the same plane as frons, or curved caudad but not at right angle to frons ................................................................................................................................................ 10

9. Head and thorax with longitudinal whitish stripe along midline from apex of postclypeus to end of mesonotum bordered with dark brown; frons in midline more than 2.0 × as wide as maximum width ............................................................................................................... Arcofacies Muir, 1915

– Head and thorax without longitudinal whitish stripe along midline; frons in midline about 1.4 × as wide as maximum width .......................................................................... Arcofaciella Fennah, 1956

10. Scutellum with median carina strongly keeled .......................... Carinodelphax Ding & Yang, 1987

– Scutellum with median carina not keeled ........................................................................................11

11. Vertex devoid of submedian carinae ............................................................................................... 12

– Vertex with submedian carinae ....................................................................................................... 13

12. Lateral carinae of pronotum reaching posterior margin; parameres divergent apically ..................... ............................................................................................................................ Gufacies Ding, 2006

– Lateral carinae of pronotum not reaching posterior margin; parameres convergent apically ............ ........................................................................................................... Mucillnata Qin & Zhang, 2010

13. Antennal segments fairly long, reaching or surpassing apex of clypeus ........................................ 14

– Antennal segments short, at most reaching anteclypeus ................................................................ 16

14. Male anal segment without process ........................................................ Lauriana Ren & Qin, 2014

– Male anal segment with process at left laterodistal angle .............................................................. 15

15. Submedian carinae of vertex percurrent and uniting at apex; male anal segment with cluster of hairlike setae at base of the left laterodistal process .................................... Malaxella Ding & Hu, 1986

– Submedian carinae of vertex uniting before apex of vertex; male anal segment bare at base of left laterodistal process ........................................................................................ Malaxa Melichar, 1914

16. Post-tibial spur devoid of apical tooth ........................................... Paranectopia Ding & Tian, 1981

– Post-tibial spur with apical tooth .................................................................................................... 17

17. Lateral carinae of pronotum not reaching hind margins ................................................................. 18

– Lateral carinae of pronotum reaching hind margins ....................................................................... 21

18. Anterior margin of vertex rounded ......................................................... Epeurysa Matsumura, 1900

– Anterior margin of vertex truncate or sinuate ................................................................................. 19

19. Median carina of frons not forked; parameres divergent apically ................. Mirocauda Chen, 2003

– Median carina of frons forked at basal third; parameres convergent apically ................................ 20

20. Submedian carinae of vertex uniting at apex .................................... Laticlypenus Ding & Hu, 2013

– Submedian carinae of vertex not confluent at apex ............................ Carinofrons Chen & Li, 2000

21. Anterior margin of vertex evenly rounded or truncated ................................................................. 22

– Anterior margin of vertex distinctly sinuate ................................................................................... 23

22. In profile, posterior margin of male pygofer strongly incised .... Specinervures Kuoh & Ding, 1980

– In profile, posterior margin of male pygofer not incised ......... Bambusiphaga Huang & Ding, 1979

23. Parameres convergent apically; male pygofer with laterocaudal margin strongly produced in pillarlike projection at each side .................................................... Neocarinodelphax Chen & Tsai, 2009

– Parameres divergent apically; male pygofer with laterocaudal margin sinuate but not produced ..... ............................................................................................................... Yuanchia Chen & Tsai, 2009