Genus: Oral polykinetids straight, never sigmoid (Illustrated Guide, 1985).
Small, ovoid or pyriform, anterior pointed; cytostome anterior 1/3 of body where an undulating membrane
on the right and three small membranelles on the left; macrostome forms with large buccal ciliation;
somatic ciliation complete; a contractile vacuole terminal; a spherical macronucleus central (Carey, 1992).
Images of collecting locality:
Drainage ditch, Tanadare-fureai-no-mori (& Center for Environmental Science), Kisai town, Saitama Pref., Japan, March 11, 2006 by Y. Tsukii