Genus: Unicells, planktonic; cell body spherical, surrounded by many elongated spiny projections, 1/3 from their base thickened, remainings hairly; a single chloroplast cup-shaped, with a pyrenoid (Guide book to the "Photomicrographs of the Freshwater Algae", 1998). Species: Cell body spherical, 8-15 μm in diam., spiny projections 30-38 μm long (Introduction to the Freshwater Algae, 1999).

50 μm 100 μm 150 μm; x 400 : 31 μm 63 μm 94 μm; x 640