Key to species of genus Brithura

1. Wings (male) with costal border opposite stigma bulged (Fig. 1) ............................................................................... 2

- Wings with costal border smooth in either sex (Fig. 2) ................................................................................................ 8

2. Wings (male) with costal border opposite stigma broken and toothed......................................................................... 3

- Wings (male) with costal border opposite stigma unbroken ........................................................................................ 4

3. Pleura dark brown, uniform in color except by pale dorsal surface of pleurotergal tubercle; antennal flagellum brownish yellow; male hypopygium with outer spine of outer gonostylus large and conspicuous ............................... ..................................................................................................................................................... fracticosta Alexander

- Pleura reddish brown, variegated with silvery, additional to pale pleurotergal tubercle; antennal flagellum uniformly dark brown; male hypopygium with outer spine of outer gonostylus small and thin ............... fractistigma Alexander

4. Femora with conspicuously subterminal ring............................................................................................................... 5

- Femora not as above .................................................................................................................................................... 6

5. Femora brownish yellow, apical ring yellow, preceded by a narrow black ring; outer gonostylus with two dissimilar spines at middle outer side .................................................................................................................... crassa Edwards

- Femora light brown with a narrow virtually terminal yellow ring, preceded by a subequal brown annulus; outer gonostylus not as above ............................................................................................................. nielseniana Alexander

6. Femora reddish brown, outer ends narrowly pale yellow, extreme apical border brown; outer gonostylus at near apex with a cylindrical finger-like lobe on outer margin ..................................................................... keiliniana Alexander

- Femora unmarked or only with an inconspicuous subterminal ring; outer gonostylus not as above .......................... 7

7. Abdominal tergites dark brown; outer gonostylus slightly bent forward, basal outer margin with an erect slender rod ......................................................................................................................................................... imperfecta Brunetti

- Abdominal tergites light brownish orange; outer gonostylus apically bent forward greatly with a short subtriangular posterior process (Fig. 5) .............................................................................................................. jinpingensis sp. nov.

8. Femora with conspicuously subterminal ring .............................................................................................................. 9

- Femora without subterminal ring ............................................................................................................................... 10

9. Fore and middle femora yellow with a narrow dark brown subterminal ring, posterior femur uniformly yellow; outer gonostylus anteriorly with a long slender rod ............................................................................... brulleana Alexander

- Femora brown with tips black, preceded by a yellow subterminal ring; outer gonostylus with a short slender rod at outer margin ....................................................................................................................................... sancta Alexander

10. Tip of vertical tubercle polished, light yellow; abdominal tergites uniformly orange, outer lateral angles not pale .... .................................................................................................................................................... argyrospila Alexander

- Vertical tubercle uniformly darkened; color of abdominal tergites not as above, outer lateral angles of basal abdomi- nal tergites pale ........................................................................................................................................................... 11

11. Abdominal tergites cinnamon brown; outer gonostylus with two processes terminating in long slender rod .............. ....................................................................................................................................................... nymphica Alexander

- Abdominal tergites dark orange; outer gonostylus with two lobe-like processes (Fig. 9) .......... guangxiensis sp. nov.