Micrasteria sp. Agardh, 1827
All members are unicellular except for a filamentous species. Generally, the cells have lengths somewhat greater then the breadths. The cells are bilaterally symmetrical and strongly compressed. The median constriction is always deep and mostly linear to sublinear. The front outline of the semicells are semicircular to hexagonal. The cell walls are generally smooth although some species have rows of marginal spines or spines all over the wall. The semicell has a single, massive, plate-like, axial chloroplast with numerous pyrenoids.
These desmids occur in the freshwater plankton. There is a wide range of shapes depending on the species.
Conjugation between adult cells results in a zygote that germinate to give daughter cells.
Bold, H. C., C. J. Alexopoulos & T. Delevoryas, 1987. Morphology of plants and fungi. Harper & Row, New York. (5th ed.). 912pp.