A short filament of Sphaerozosma vertebratum. Notice the rod-like, apical tubercles between adjoining cells.

Cell dimensions (L x B): 17 x 20 µm



Desmid of the month
May 2007

Sphaerozosma vertebratum

Like Spondylosium, Sphaerozosma is a filamentous genus composed of Cosmarium-like cells. The difference with Spondylosium is in the occurrence of a couple of rod-like processes at each of the cell apices. By way of those processes cells are interconnected to filamentous colonies. In Sphaerozosma vertebratum the apical processes, located near the middle of the apex, are short and incidentally even may be overlooked. In the Netherlands it is a very rare species recorded from only a few mesotrophic moorland pools.

two more fragmented filaments of Sphaerozosma vertebratum

Two more (fragmented) filaments of Sphaerozosma vertebratum. Apical tubercles are hardly visible in this picture.