Desmid of the month
September 2008
Actinotaenium cucurbita
Actinotaenium
cucurbita is characterized by more or less
cylindric cells, broadly rounded at the apex, and by stelloid chloroplasts
incorporating a central pyrenoid. An important additional feature is found in
the marked pore fields easily to be distinguished in empty cells, even at low
magnification.
In the Netherlands
(and elsewhere in Europe) A. cucurbita is one of the most common desmid
species in acidic, oligotrophic bogs. It may stand desiccation for longer
periods, so may also be encountered in emerse Sphagnum hummocks and on
wet substrates that dry out periodically. |
Image © Marien van Westen
Actinotaenium
cucurbita. Notice the stelloid chloroplasts (one
per semicell) each of them incorporating a big, globular pyrenoid.
Cell dimensions (L
x B): 40 x 20 µm |