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).

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

Euplotes, x 400, x 640, Uruguay Nov. 1999, photo by Yuuji Tsukii

E. aspheronicus Agamaliev, 1966: Cell body ellipsoid, not ornamented, 60 μm long; peristome 1/2 of the body length; 9 frontoventral, 5 transverse, 4 caudal cirri; macronucleus C-shaped (Carey, 1992).

E. zenkewitchi Burkovsky, 1970: Cell body elongate rather than ovoid, not ornamented, 80 μm long; peristome narrow, 1/2 of the body length; 9 frontoventral, 5 transverse, 3 or 4 caudal cirri; macronucleus C-shaped (Carey, 1992).

E. cristatus Kahl, 1930-5: Cell body small and ovoid, dorsally six prominent ridges, 60 μm long; peristome narrow, 1/2 of the body length; 10 frontoventral, 5 transverse, 4 caudal cirri; macronucleus C-shaped (Carey, 1992).