Genus (Dujardin, 1841): Test round or oval in cross-section; pseudostome anteroventral;
scales in regular rows (Illustrated Guide, 1985).
Species: Test 25-60 μm long, 14-40 μm wide, pseudostome 6.5-16 μm wide (Cash, The British Freshwater Rhizopoda and Heliozoa vol. III, 1915).
Images of collecting locality:
No.5, Shibayachi marsh, Odate city, Akita Pref., Japan, September 22, 2007 by Y. Tsukii