Key to species of Okubasca Dworakowska

1. Aedeagus with preatrium shorter than shaft in lateral view..................................................... 2

- Aedeagus with preatrium equal to or longer than shaft in lateral view............................................ 4

2. Anal tube appendage curved posterad at apex, apex of aedeagus with lateral teeth.............. O. dianella (Qin & Zhang)

- Anal tube appendage straight or curved anterad; apex of aedeagus without teeth.................................... 3

3. Aedeagal shaft with toothlike projection on dorsal margin of shaft near midlength.............. O. paracalvata Yu & Yang

- Aedeagal shaft with dorsal margin smooth, without tooth..................................... O. calvata (Qin & Liu)

4. Male pygofer ventral appendage extended to pygofer lobe apex (Fig. 8); anal tube appendage weakly developed, lobe-like (Figs 8, 10, 11)............................................................... O. wuningensis Zhang & Xu, sp. nov.

- Male pygofer ventral appendage undeveloped, not extended to pygofer lobe apex; anal tube appendage elongate, extended about half distance to ventral margin of genital capsule....................................................... 5

5. Aedeagus in lateral view with shaft broadest in middle, with lateral teeth subapically............. O. okubella (Matsumura)

- Aedeagus in lateral view with shaft broadest basally, without lateral teeth...................... O. convoluta Yu & Yang