Coenobium

For "coenobium" in the sense of communal monasticism, see Cenobite

Pediastrum duplex

A coenobium (plural coenobia) is a colony containing a fixed number of cells, with little or no specialization. They occur in several groups of algae. The cells are often embedded in a mucilaginous matrix and may be motile or non-motile.

Examples include Volvox and its relatives, Scenedesmus, Pediastrum, and Hydrodictyon.