Staurastrum diacanthum

St. diacanthum belongs to the section of Staurastrum species characterized by arm-like cell processes. It is closely related to  St. paradoxum * , the type species of the genus Staurastrum. In apical view, the semicell body is 3- or 4-radiate, each of the angles being attenuated to form a rather long, dentate process tipped with some four stout spines. Characteristic of St. diacanthum is the presence of two extra large, spiny, dorsal dentations near the base of each process. In the Netherlands, St. diacanthum is of rather rare occurrence in acidic, oligotrophic bogs and moorland pools.

* Some authors consider St. diacanthum a variety of St. paradoxum

Image © Henk Schulp

Cell of St. diacanthum in frontal view. Of each semicell there are only two processes in focus (the third one is projected towards the observer).

Cell dimensions (L x B) = ca 55 x 70 µm

<< Image on the left:

Cell of St. diacanthum in apical view. Note the pair of furcate spines near the base of each of the three processes.