Stauridium

Stauridium is a genus of green algae in the family Hydrodictyaceae. It is very common in freshwater regions throughout the world.

==Description== Stauridium forms flat colonies, termed coenobia, of cells in powers of two, usually four, eight, or 16. Coenobia are disc-shaped in outline, composed of cells laid contiguously next to each other with no spaces in between cells. The marginal cells are trapezoidal, with (in S. tetras) or without (in S. privum) a V-shaped incision in the middle. The cell wall is smooth or covered in granules, warts, or ridges. Cells have one chloroplast filling the cell, each with a single pyrenoid.