A group of plants the members of which are usually regarded as algae, although they resemble bryophytes in the structure of the male gametes and in the presence of a sterile envelope enclosing the sex organs. Many species are heavily calcified. Fossil charophytes (from the Triassic on-wards) are known only by their calcified oogonia, which often have a spiral ornament. Charophytes are aquatic, occurring primarily in fresh water, although some species are found in brackish water. Charophytes are sometimes included in a class within the division Chlorophyta and sometimes as a dis-tinct division (Charophyta). Genera include Chara and Nitella. See also stonewort.
Subjects: Plant Sciences and Forestry.