Cell of Gonatozygon brebissonii. Notice the finely granulate cell wall and the axile, plate-like chloroplasts (provided with a longitudinal, median ridge and some two pyrenoids)

Cell dimensions (L x B): 115 x 8 µm

 


Desmid of the month
September 2009

Gonatozygon brebissonii

Unlike in Gonatozygon monotaenium cells of G. brebissonii rather gradually taper towards the apices, so are fusiform rather than cylindric in shape. Moreover, cells are often pretty abruptly attenuated just below the truncate ends giving rise to capitate apices. The wall of the vegetative cell is beset with delicate, rounded or acute granules, but zygospores (only rarely encountered) are perfectly smooth-walled. In the Netherlands, G. brebissonii is occasionally found in various types of mesotrophic, slightly acidic to pH-neutral water bodies.

Another, more slender cell of G. brebissonii

Gonatozygon brebissoniiImage © Marien van Westen

A rather thick-set cell of G. brebissonii shortly after division, the lower semicell showing a narrower segment, to be interpreted as a girdle band, next to the site of division. 

Gonatozygon brebissonii, zygosporeImage © Henk Schulp

Zygospore of G. brebissonii