Genus: Outer envelop made of two kinds of siliceous element; tangential scales or pearls and radial
spicules (Illustrated Guide, 1985).
Similar genus ->> Nuclearia; Rabdiophrys sp. ?,
cell body nearly spherical, 24 μm in diam., axopodia very thin,
x 640, near Oh-hashi (large bridge), Asa-kawa (Asa river), Hachioji city, Tokyo, Japan, March 26, 2005 by Y. Tsukii
94 μm; x 640