Image © Marien van Westen

Staurastrum lapponicum. Notice cell that is as long as broad with elliptic semicells.

Cell dimensions (L x B): 37 x 37 µm

Image © Marien van Westen

Empty semicell of Staurastrum lapponicum in apical view showing regular, concentric series of granules around the poles.

 

 

Desmid of the month
March 2018

Staurastrum lapponicum

Staurastrum lapponicum belongs to the group of Staurastra that are characterized by a uniformly granulate cell wall. It is to be distinguished from the widely distributed species Staurastrum punctulatum (species of September 2017) by cells that are about as long as broad, versus longer than broad in St. punctulatum. Moreover, granules are finer, closer together and distributed in more regular series than in St. punctulatum. In the Netherlands, Staurastrum lapponicum is widely distributed in various kinds of mesotrophic pools.


Image © Marien van Westen

Largely empty cell of Staurastrum lapponicum in rear view. Notice regular series of closely set granules.


SEM image © Jan Šťastný

SEM image of St. lapponicum