Species: Colonies of 4, 8, 16 or 32 cells, pyramidal, cubical or polygonal in shape; cells conical or tetrahedral in shape, sides concave, corners truncated, 6-17 μm in diam.; cells connected to adjacent cells by the projected corners forming a large polygonal space between the cells (Photomicrographs of the Freshwater Algae, vol. 2, 1984).

31 μm 63 μm 94 μm; x 640