A REAPPRAISAL OF THE SCARIDIIDAE (ROTIFERA, MONOGONONTA)

The morphology, systematics and distribution of the rotifer genus Scar idium Ehrenberg, 1830 are revised. The genus is transferred from Notom matidae to Scaridiidae, which is reinstated. In all, five species are recognized, two of which, S. montanum sp. n. and S. grandis sp. n., ar e new to science. Descriptions, a brief biometrical analysis and a key to the species are provided. Scaridium longicaudum (O.F. Muller, 1786 ) is cosmopolitic, S. bostjani Daems and Dumont, 1974 is probably a co smopolitic warm stenotherm, S. elegans Segers and De Meester, 1994 is pantropic, S. montanum sp. n. occurs in the Mediterranean region and S . grandis sp. n. is recorded from Cameroon, Nigeria and Thailand.