Cosmarium pyramidatum
Image © Marien van Westen

Cosmarium pyramidatum in frontal view. Notice rather large cell size and about pyramidal semicells. Upper semicell with three, lower semicell with two pyrenoids.
Cell dimensions (L x B): 72 x 47 µm


 

 

Desmid of the month
October 2017

Cosmarium pyramidatum

C. pyramidatum is a rather large-sized Cosmarium species with smooth-walled cells. Semicells are more or less pyramidal in outline. The cell wall is finely but distinctly punctate and the chloroplast contains two or more pyrenoids. In the Netherlands, C. pyramidatum is of occasional occurrence in acidic, oligotrophic bogs and moorland pools.

Dead, empty cell of C. pyramidatum showing cell wall punctation

Another cell of C. pyramidatum in frontal view

Another cell of C. pyramidatum in frontal view

Cell of C. pyramidatum in apical view

SEM picture of C. pyramidatum showing equally distributed, fine cell wall pores.

 

 

SEM picture of C. pyramidatum in more detail

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