Genus: Greater part of axopodia and cell body covered by a thick gelatinous mantle (Kudo, 1966).
Species:
Sphaerastrum sp.,
cell body 30 μm in diam., axonemes up to 55 μm long,
x 640, Akebono marsh, Nidanuma (Nitanuma), Tsuchiyu-onsen, Fukushima city, Fukushima Pref., Japan, October 28, 2005 by Y. Tsukii
31 μm
63 μm
94 μm; x 640