Family: Unicells; cell body spherical or broad ellipsoidal;
chloroplasts 1 to several in number, cup-shaped or plate-like, reticulated or star-shaped;
with or without pyrenoids; reproduction by autospores and zoospores; many species found in soil
(Illustrations of The Japanese Fresh-water Algae, 1977).
Genus: (Guide book to the "Photomicrographs of the Freshwater Algae", 1998).