Key to females of Dianphasma Chen & He, 1997

1. Posterior apices of wing-rudiments on metanotum not reaching anterior margin of median segment.................... 2.

- Posterior apices of wing-rudiments on metanotum reaching anterior margin of median segment....................... 3.

2. Fifth to sixth abdominal tergites with a flattened elevation posteromedially, anterior area of sixth abdominal tergum lacking paired humps................................................................................... D. cheni

- Fifth to sixth abdominal tergites with a tubercle posteromedially, anterior area of sixth abdominal tergum with a pair of humps......................................................................................... D. yui sp. nov.

3. Fifth abdominal tergum to anal segment granulated................................................ D. microptera

- Fifth abdominal tergum to anal segment lacking granulation............................. D. sparsigranulatum sp. nov.