Key for identification of suctorian ciliates belong to the genus Rhabdophrya
1(4) Macronucleus ellipsoidal.
2(3) Stalk long, provided with physon................................................. Rhabdophrya mumbaiensis n. sp.
3(2) Stalk short, provided with epicone....................................................... Rhabdophrya trimorpha .
4(1) Macronucleus ribbon-like.
5(6) Stalk long, but its length does not exceed half the length of the body, without widening.............. Rhabdophrya truncata .
6(7) Stalk short, with epicone.
7(8) Body converged to the top............................................................ Rhabdophrya populiformis .
8(7) Body not converged to the top.......................................................... Rhabdophrya nymphonis .