Desmodesmus (Radiococcaceae)

Diagnostic features

Colonial chlorophyte with roughly ovoid cells, most often seen as colonies of 4 cells arranged side to side (although colonies of up to 32 cells are possible). The cell walls are ornamented with spines, and sometimes warts and ribs (although these are harder to see).  Spines may sometimes be absent, and Desmodesmus may also occur as a unicell or in pairs under some conditions.  In some species, spine production has been demonstrated to occur in the presence of herbivores, the spines making the cells too large to be grazed.  Chloroplasts contain pyrenoids. Similar to Scenedesmus, but wall ornamentation does not occur in the latter.

Typical habitats

Found in the plankton of nutrient-rich ponds including sewage ponds

Classification