Genus: Body ovoid, inflexible; ventral surface flattened, dorsal surface convex; peristome broadly triangular (Kudo, 1966). Cell body is ovoid, dorsoventrally flattened; dorsal surface may be equipped with some ornamentation; three groups of cirri (frontoventral, transverse & caudal); macronucleus C-shaped, "3"-shaped, or horsehoe-shaped (Carey, 1992). Species:

50 μm 100 μm 150 μm; x 400 : 31 μm 63 μm 94 μm; x 640