a class of unicellular and colonial blue-green algae. The cells are differentiated into a base and an apex. The algae are always attached to a substrate and often have more or less fully formed thalli. In the thallus the filaments of the cells usually concresce at their sides, forming a false parenchyma and sometimes radically changing the initial structure of the colony. The cell membranes are for the most part thick; they may be strong or mucilaginous. They are sometimes bright orange or red-brown in color. Reproduction is effected by means of endospores or exospores.
The Chamaesiphonophyceae include four orders: Pleurocapsales, Dermocarpales, Siphonemales, and Entonemales. The orders embrace approximately 25 genera. The algae are found in both fresh and marine waters.