Desmid of the month
November 2011

Desmidium aptogonum

Filament of Desmidium aptogonum. Notice the large cavities in between adjacent cells.

Cell dimensions (L x B): 18 x 32 µm

The filamentous species Desmidium aptogonum much resembles D. swartzii. Like in D. swartzii, cells in frontal view are distinctly broader than long and triangular in top view. D. aptogonum mainly differs from D. swartzii by the remarkably large cavities in between adjacent cells. Moreover, cell breadth to length ratio usually is somewhat lower than in D. swartzii and the lateral sides of the semicell are more rounded. In the Netherlands D. aptogonum is of occasional occurrence, particularly in slightly acidic to pH-neutral peat pits and fen hollows.

Another filament of Desmidium aptogonum showing radiating chloroplast lobes.

SEM image of D. aptogonum.