desmid

desmid, a protist of the class Charophyceae (see Chlorophyta).

---

desmid

Desmid (Micrasterias), highly magnified

(credit: Winton Patnode—Photo Researchers)

Any of a group of one-celled, microscopic green algae characterized by great variation in cell shape. Typically the cell is divided symmetrically into semicells connected at a central point. Desmids are found worldwide, usually in acid bogs or lakes. Since most species have a limited range, the presence of specific desmids is helpful in characterizing water samples.