Cell of X. basidentatum. The cell wall in the centre of the semicell is furnished with a circle of granules. At each of the angles a number of stout spines is inserted. Notice also the additional granules near the basal angles.

Cell dimensions (L x B): 82 x 75 µm

 

 

Desmid of the month
August 2011

Xanthidium basidentatum

Xanthidium basidentatum differs from the allied species X. cristatum and X. fasciculatum by a more exuberant ornamentation. Each of the semicell angles is beset with a bundle of spines. In addition to that there is a number of marked granules near each of the basal angles. In the Netherlands X. basidentatum is a very rare species, encountered in acidic, mesotrophic moorland pools.

Same cell of X. basidentatum photographed at lower magnification, showing the bundles of spines at each of the semicell angles.

Xanthidium basidentatum from another Dutch population.

Cell of X. basidentatum in apical view

Cell of X. basidentatum in lateral view