Key to the species of Chinese Ocellarnaca

1 Male ninth abdominal tergite with 1 pair of small processes on posterior margin, basal area of each process with 1 spine.... ................................................................................................... 2

- Male ninth abdominal tergite with 1 pair of large processes on posterior marin, middle area or nearly apical area of each with 1 spine............................................................................................... 6

2 Posterior margin of male ninth abdominal tergite as broad as basal area, not narrowing, lateral margin with 1 pair of small processes, widely spaced from each other........................................................ O. brevicauda

- Posterior margin of male ninth abdominal tergite narrowing, middle area with 1 pair of large processes, closely connected each other............................................................................................... 3

3 Frons reddish brown................................................................................... 4

- Frons black.......................................................................................... 5

4 The spine of process in male ninth abdominal tergite large, which basal area wider, strongly narrowing, slightly curved; apical area of female seventh abdominal sternite with 1 pair of lobiform processes............................... O. angulata

- The spine of process in male ninth abdominal tergite small, nearly triangular; apical area of female seventh abdominal sternite with 1 process, its apex bifurcate............................................................ O. fuscotessellata

5 Black stripes of posterior margin of pronotal lateral lobes extendting to forward........................... O. emeiensis

- Black stripes of posterior margin of pronotal loteral lobes not extending to forward........................... O. wolffi

6 Male subgenital plate with 1 conspicuous process............................................................ 9

- Male subgenital plate without process............................................................. O. furcifera

7 Apical area of male subgenital plate with 1 long conical process, apex acute; apical area of female seventh abdominal sternum with 1 short conical process...................................................................... O. conica

- Middle area of male subgenital plate with 1 short conical process, apex obtuse; apical area of female seventh abdominal stergite with 1 long cylinderical process......................................................................... 10

8 Body large, brown, dark area of wing membranous very small; the process of female seventh abdominal sternum stout, ventral margin of apical area obviously expanded........................................................... O. braueri

- Body small, brown to dark brown, dark area of wing membranous very large, nearly occupying whole membrance of cells; the process of female seventh abdominal sternite slender, ventral margin of apical area slightly or not expanded....... O. fallax