Family & Genus: With branching, anastomosing pseudopodia, mainly at extermities (Illustrated Guide, 1985). When inactive, rounded or ovoid; when active, expanded; 1 or more contractile vacuoles; fresh water (Kudo, 1966). Species:

31 μm 63 μm 94 μm; x 640

Images of collecting locality: Yakebe-ike (pond), Sayama park, Higashi-Murayama city, Tokyo, Japan, February 11, 2006 by Y. Tsukii