Desmids are unicellular, microscopic, green algae which are widely distributed in a variety of freshwater habitats, although they are typically found in clear oligotrophic water.
Taxonomically they are members the Closteriinea or Desmidiinea, however, species grouped in the Mesotaeniaceae (saccoderm desmids) are also usually included in the desmids. Although the cell shape varies, they are characteristically symmetrical, often with two semi-cells joined by a bridge, and can have a highly ornamented cell wall. The cell shape and texture are important characteristics used in the identification of desmids.
Over 900 species of desmids have been recorded in the British Isles but in the Outer Hebrides little is known about which species are present or their distribution. The only records on the NBN Atlas Scotland are those published by Outer Hebrides Biological Recording, the results of other surveys remain either unpublished or in the scientific literature.
This is a new project and we would appreciate records of species recorded in the islands or information on the sources of published material.