Treatise on Invertebrate Paleontology (2005), Part B, Protoctista 1, vol. 1. Shipped INTERNATIONAL ONLY

The Charophyta, commonly called charophytes or stoneworts, are green algae that occur worldwide, sometimes abundantly, in fresh and brackish water. Long considered a distinctive group, recent morphological and molecular studies have shown conclusively that charophytes are members of the evolutionary lineage of green algae that gave rise to land plants. Their importance is enhanced by a fossil record more complete and well studied than nearly any other calcareous algae, with the exception of the Dasycladales.