Genus: Filamentous colonies covered with mucilagenous sheath; 2, 3 or 4 daughter cells linearly connected by thin filament derived from their mother cell wall; cell body spherical; a single chloroplast parietal with a pyrenoid (Yamagishi, Introduction to the Freshwater Algae, 1999). Species:

31 μm 63 μm 94 μm; x 640