ULTRASTRUCTURAL OBSERVATIONS ON THE SPERMIOGENESIS IN THE PAROTOPLANINAE (PLATHELMINTHES, PROSERIATA) WITH SPECIAL REFERENCE TO A STRIATED APPENDAGE OF THE INTERCENTRIOLAR BODY

The spermiogenesis of three species of the Parotoplaninae (Otoplanidae , Proseriata) is described based on electron-microscopical observation s. Special reference is given to organelles which do not persist in ma ture male gametes. One of these organelles is a striated appendage of the intercentriolar body. This differentiation has not been reported f rom any other plathelminth taxa up to now. The striated appendage, whi ch may serve as a strengthening element, is hypothesized to be an auta pomorphic feature of the Parotoplaninae.