Cell of Xanthidium variabile. Notice trapeziform semicells with at each angle a number of rather short spines.

Cell dimensions (L x B, exclusive of spines): 24 x 24 µm



Desmid of the month
May 2013

Xanthidium variabile

X. variabile is a rather small-sized Xanthidium species that owes its name to a variable ornamentation, in particular the number of apical spines and the appearance of the central protuberance.  Yet, it is easily to be recognized (besides its cell dimensions) by its distinctly trapeziform semicells. X. variabile is characteristic of acidic, oligotrophic bog pools. In the Netherlands, the latest find dates from more than half a century ago but recently it was encountered in a nearby moorland area in Belgian Flanders.

Cell of X. variabile in apical view. Notice prominent central papilla.

Semicell of X. variabile in isthmial view showing three spines at each of its basal angles (a fixed number contrary to the number of apical spines).