Family: Unicells; cell body spherical, ellipsoidal, or spindle-shaped; without spiny projections or stipes (Illustrations of The Japanese Fresh-water Algae, 1977).
Genus:
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Similar genus -->> Excentrosphaera;
E. gigas ?
or Excentrosphaera ?
36-65 x 11-22 μm
Koshigaya
Saitama, 2001
E. gigas ?
or Excentrosphaera ?
76 x 32 μm
Ikenokochi marsh
Tsuruga
Fukui, 2004
E. gigas ?
or Excentrosphaera ?
105 x 36 μm
Ikei-no-ike
Nasu
Tochigi, 2006