Staurastrum margaritaceum. Notice campanulate outline of the semicell body with short processes.

Cell dimensions (L x B): 33 x 28 µm

 

 

Desmid of the month
July 2018

Staurastrum margaritaceum

Cell of S. margaritaceum somewhat resemble those of S. sexcostatum (desmid of December 2011) but are a bit smaller whereas their ornamentation is less marked. Moreover, the arm-like processes are inserted near the semicell apex giving rise to a more or less campanulate outline of the semicell body (versus about elliptic in S. sexcostatum). In apical view, semicells are 4- to 6-radiate. Processes are relatively short and ornamented with concentric series of granules. Semicells at their base often with a supraisthmial whorl of granules. In the Netherlands, S. margaritaceum is a common inhabitant of acidic, oligotrophic bogs and moorland pools.

Empty, 4-radiate semicell of S. margaritaceum in apical view.

Empty cell of S. margaritaceum showing pattern of cell wall granulation.

SEM picture of S. margaritaceum in frontal view.

SEM picture of S. margaritaceum in apical view.