Genus: Oral polykinetid 3 rectangular; oral area midventral (Illustrated Guide, 1985).
Cytostome right of median line in posterior half; with 3-4 caudal cilia; contractile vacuole terminal
(Kudo, 1966).
Species:
Cinetocilum margaritaceum Perty, 1852:
Cell body 15-45 μm long; oral area in lower right quadrant of ventral surface;
body ovoid, anterior and posterior rounded (Carey, 1992).