Genus: Test elastic, punctate; pseudostome round;
few plate-like attached particles (Illustrated Guide, 1985).
Envelope (test) thin, hyaline, changeable with body form; usually elongate-oval
with rounded posterior end; narrowed at other half; envelope finely punctated with a few small plates;
aperture round; cytoplasm clear (Kudo, 1966).
Images of collecting locality:
Ushidome-ike (pond), Norikura highland, Azumi, Matsumoto city, Nagano Pref., Japan, November 4, 2007 by Y. Tsukii