desmid

Etymology
From.

Noun

 * 1) Any of about 5000 species of mostly unicellular freshwater green algae belonging to the order Desmidiales.
 * 2) * 1981, Alan J. Brook, The Biology of Desmids, University of California Press, Botanical Monographs 16, page 1
 * Desmids, which are exclusively freshwater algae, are so named because the first of these green microorganisms to be described were thought to be pairs of cells joined together, and the Greek word 'desmos' means a bond or chain.