Key to the species in the genus Paleosisyra
1 In forewing radius posterior 3-branched....................................................... .. P. minor n. sp.
- In forewing radius posterior 4-branched................................................................... 2
2 In male genitalia ectoproct bulbous, coxopodite digitiform, curved ventrad............................ P. electrobaltica
- In male genitalia ectoproct broader than long, coxopodite long, straight................................... P. eocenica