The following points highlight the two families under which zygamatales has been classified. The families are: 1. Zygnemataceae 2. Desmidiaceae. Family # 1. Zygnemataceae: This family includes fresh-water multicellular filamentous forms of algae. Genus Spirogyra of Zygnemataceae: It is one of the common green algae occurring chiefly in ponds, pools, ditches, and similar other places. […]