[2] Chlorotetraedron consists of cells up that are solitary or rarely found in irregular groups.

[2] Cells are generally angular in shape, varying from tetrahedral to polyhedral.

In cultivation, the cells may become nearly spherical, but the remnants of the angles are present as papillae.

Cells contain one nucleus when young, later having multiple nuclei, and a single parietal chloroplast.

However, Tetraedron has uninucleate cells (i.e. with a single nucleus at maturity), only produces autospores and not zoospores, and has a rough outer sporopollenin layer.