Staurodesmus dejectus. Notice the upwardly projected apical spines and the slightly elongate isthmus.

Cell dimensions (L x B, inclusive of spines): 34 x 32 µm



Desmid of the month
December 2013

Staurodesmus dejectus

Cells of Staurodesmus dejectus usually are triadiate. Semicells are bowl-shaped and each of the apical angles is furnished with a rather short, upwardly projected spine. An important, additional characteristic is in the slightly elongate isthmus. Zygospores, as in most Staurodesmus species, are globose and provided with stout spines. Std. dejectus is a widely distributed species. In the Netherlands it is rather common in meso-oligotrophic fens and moorland pools; zygospores are but incidentally encountered.


Staurodesmus dejectus, zygospore.

Cell of Std. dejectus in apical view. As in many Staurodesmus species, spines at the angles are bent (anti)clockwise.