Key to genera of Hemisphaeriini

1. Tegmen with claval suture …………………………………………………………………………2

– Tegmen without claval suture ………………………………………………………………………4

2. Tegmen with claval suture distinct in basal ¼ of wing; metope with median carina rudimentary in its apical part (Genezdilov 2015: figs 1–3) …………………… Bruneastrum Gnezdilov, 2015

– Tegmen with claval suture well-developed; metope with complete median carina or median carina absent ………………………………………………………………………………………3

3. Metope elongate, with median carina, without tubercules (Chen et al. 2014: figs 2-35, 2-36) …………………………………………………… Neohemisphaerius Chen, Zhang & Chang, 2014

– Metope almost as wide as long in middle line, without median carina, with a row of tubercules along lateral margin (Chen et al. 2014: fig. 2-33) ………… Paramongoliana Chen, Zhang & Chang, 2014

4. Metope with large bulge at center (Genezdilov 2013 b: figs 2–4) … Bolbosphaerius Gnezdilov, 2013

– Metope flat or slightly elevated in median area, without such bulge (Figs 1B, D, F–G, J, L, 2C, 8B, 9D, 10H)…………………………………………………………………………………………………5

5. Tegmen depressed at base, costal margin moderately convex at basal one third as “relief shoulder” (Figs 1A, C, 7A) ……………………………………………………………………………………6

– Tegmen not as above (Figs 1E, H–I, K, 8A, 9A, 10A) ……………………………………………8

6. Coryphe almost as wide as long, anteclypeus angularly rounded (Fig. 6 A–B) … Gergithus Stål, 1870

– Coryphe distinctly longer than wide, anteclypeus flat (Fig. 1 A–D) ………………………………7

7. Pronotum with median carina; anterior margin not foliate and elevated (Fig. 1C). Metatibiotarsal formula 6–8–2 …………………………… Neogergithoides Sun, Meng & Wang, 2012

– Pronotum without median carina; anterior margin foliate and elevated (Fig. 1A). Metatibiotarsal formula 6–10–2 …………………………………………………… Macrodaruma Fennah, 1978

8. Coryphe elongate, more or less triangular (Fig. 1E) … Choutagus Zhang, Wang & Che, 2006

– Coryphe broad, quadrangular (Figs 1 H–I, K, 8A, 9A, 10A) …………………………………………9

9. Tegmen distinctly widened at basal costal margin (Figs 8B, 10A) ………………………………10

– Tegmen not widened at basal costal margin …………………………………………………11

10. Coryphe 4.5 times as wide as long; metope very broad below eyes (Fig. 10A, D) …………… …………………………………………………………………… Hemisphaeroides Melichar, 1903

– Coryphe 1.5 times as wide as long; metope not very broad below eyes (Fig. 8 A–B) ……… …………………………………………………………………………… Mongoliana Distant, 1906

11. Metope with lateral margin almost right-angled at mid-length ……………………………………12

– Metope with lateral margin not right-angled at mid-length ………………………………………13

12. Mesonotum elevated, length in midline almost equal to combined length of coryphe and pronotum; tegmen distinctly long, oblong (Melichar 1906: fig. 15) …… Hysteropterissus Melichar, 1906

– Mesonotum flat, twice combined length of coryphe and pronotum in mid line; tegmen relatively wide, nearly rhomboidal (Fig. 1K) …………………… Rotundiforma Meng, Wang & Qin, 2013

13. Clypeus with median carina (Melichar 1906: fig. 16) …………… Hysterosphaerius Melichar, 1906

– Clypeus without median carina ……………………………………………………………………14

14. Fore and mid femora dilated (Melichar 1906: fig. 14) …………………… Hemiphile Metcalf, 1952

– Fore and mid femora not dilated ……………………………………………………………………15

15. Metope with a row of tubercles and median carina (Fig. 1G) ……… Gergithoides Schumacher, 1915

– Metope without tubercles and median carina (Figs 1J, 9 C–D) ……………………………………16

16. Hind wing well-developed, longer than half length of tegmen ………… Gnezdilovius gen. nov.

– Hind wing shorter than half length of tegmen …………………………………………………17

17. Aedeagus with two processes, suspensorium indistinct …………………………………………18

– Aedeagus without process, suspensorium distinct ………………… Hemisphaerius Schaum, 1850

18. Pygofer in profile with hind margin distinctly angulated; phallobase asymmetrical at apex (Chan & Yang 1994: figs 27–30) ………………………………… Euhemisphaerius Chan & Yang, 1994

– Pygofer not distinctly angulated; phallobase symmetrical (Chan & Yang 1994: fig. 26) ………… …………………………………………………………… Epyhemisphaerius Chan & Yang, 1994