Chroococcus is a large genus of cyanobacteria whose species are difficult to differentiate. However, they are typically characterized as living in small colonies of 2, 4, or 8 cells that are surrounded by a clear, mucus sheath. Occasionally unicells or colonies with as many as 16 individuals may occur as well. The sheaths of Chroococcus colonies are sometimes moderately stratified or layered, as demonstrated by C. turgidus, which is most often found in soft water habitats frequented by desmids. Also, the cytoplasm of the cells contains photosynthetic pigments and may exhibit a granular texture.