Desmid of the month
January 2006
Xanthidium armatum
Xanthidium armatum is a conspicuous desmid that is readily to be recognized. In frontal view, semicells are about octangular in outline and marked by stout, bi-or trifurcate spines on the angles. The semicell centre is somewhat inflated and furnished with a corona of simple or bifurcate teeth. In the Netherlands, X. armatum is confined to oligotrophic habitats where there is a slight input of minerals from the subsoil. As a consequence of the highly acidified precipitation in the last century its occurrence is much decreased. Today it is a rare species.
Image © Wim van Egmond
Cell of Xanthidium armatum(in frontal view) marked by stout, furcate spines on the angles.
Cell dimensions (L x B): 150 x 100 µm.
