Key to males of Planososibia Seow-Choen, 2016 from China
1. Posterior apices of alae extending beyond fifth abdominal tergum.............................................. 2.
- Posterior apices of alae not extending beyond fifth abdominal tergum........................................... 4.
2. Posterior margin of tegmina with yellow margin..................................................... P. yunnana
- Posterior margin of tegmina lacking yellow margin.......................................................... 3.
3. Posterior margin of anal abdominal segment truncate.................................................. P. cornuta
- Posterior margin of anal abdominal segment emarginated........................................... P. liui sp. nov.
4. Posterior margin of anal segment with emargination.......................................... P. brevialata sp. nov.
- Posterior margin of anal segment rounded................................................................. 5.
5. Cerci strongly curved inwards.................................................................. P. platycerca
- Cerci weakly curved inwards........................................................................... 6.
6. Posterior apices of alae extending beyond fourth abdominal tergum...................................... P. truncata
- Posterior apices of alae not extending beyond fourth abdominal tergum........................ P. qiongensis comb. nov.