Closterium acerosum Image © Alfred van Geest

Closterium acerosum. Notice that the cell is only slightly curved (almost straight in its middle part) and marked by conical, somewhat recurved apices.

Cell dimensions (L x B): 365 x 30 µm



Desmid of the month
March 2012

Closterium acerosum

Closterium acerosum is marked by fairly stout, slightly curved to almost straight cells with a bit conical, often slightly recurved apices. The cell wall looks smooth or very delicately striate, colourless or a bit brownish. Zygospores are globular and smooth-walled. In its ecology Cl. acerosum deviates from most other desmids in that it is often met with in organically contaminated waters. It also stands relatively high concentrations of mineral salts. In the Netherlands Cl. acerosum is of common occurrence in benthos of alkaline, saprobic waters. Zygospores have been encountered only incidentally.


detail of cell wallImage © Alfred van Geest

Detail of cell wall showing a delicate striation.

cell amongst detritus Image © Henk Schulp

A cell of Closterium acerosum amongst detritus, bacteria and other microbes indicating an organically contaminated environment.

globular, smooth walled zygosporeImage © Henk Schulp

Conjugating cells of Closterium acerosum producing a globular, smooth-walled zygospore.