Genus: Filamentous algae without branching, no rhizoids, covered with gelatinous sheath;
cell body cylindrical or ellipsoidal, cells attached side by side or separated;
a single chloroplast band-form, with a pyrenoid
(Guide book to the "Photomicrographs of the Freshwater Algae", 1998).
Species: Filament covered with a thick gelatinous coat; 2 or 4 cells closely contacted; cell body elongated ellipsoid or ovoid, 4-6 μm long, 7-9 μm wide; chloroplasts parietal, with a single pyrenoid (Photomicrographs of the Freshwater Algae, vol.4, 1985).