Pediastrum duplex

Pediastrum duplex is a type species of fresh water green algae in the genus pediastrum.

They form nonmotile coenobia (colonies) with a fixed number of cells. These coenobia are flat and have a circular shape. The cell bodies are polygonal, are granulated and have horn-like projections. They reproduce these autocolonies asexually. The colonies usually contain 8 to 32 cells, with examples of 4, 64 or 128 occurring rarely.