Wikipedia
Goniaceae
In taxonomy, the Goniaceae are a family of algae, specifically of the Chlamydomonadales, that includes the genera Astrephomene and Gonium. Members of the Goniaceae are distinguished from those of the Volvocaceae by having each cell surrounded by a tripartite boundary of the extracellular matrix, as opposed to the entire colony being surrounded by the tripartite boundary in Volvocaceae.