Cell of Cosmarium crenulatum. Notice outline of the semicells with eight, about equally sized undulations.
Cell dimensions (L x B): 30 x 22 µm


Desmid of the month
August 2023

Cosmarium crenulatum

Cosmarium crenulatum could be compared with C. impressulum (desmid of March 2023). Both species are characterized by small, smooth-walled cells with semicells that in frontal view are marked by an 8-undulate outline. However, whereas the marginal undulations in C. impressulum are relatively weak and unevenly placed, those in C. crenulatum are distinctly deeper and more regularly positioned. In the Netherlands, C. crenulatum is of rather common occurrence in various mesotrophic water bodies.

Empty cell of C. crenulatum of Cosmarium crenulatum. Notice that cell wall is destitute of any granulation.

SEM picture of C. crenulatum. Notice faint scrobiculation of the cell wall.