Cell of Penium spirostriolatum (var. amplificatum). Notice cell wall girdle bands marked by irregular transitions in the cell outline.

Cell dimensions (L x B): ca 180 x 20 µm


Desmid of the month
December 2008

Penium spirostriolatum

Penium spirostriolatum differs from P. margaritaceum by its cell wall sculpture consisting of longitudinal, more or less spiralized ridges (instead of scattered granules). Cells are roughly cylindric in shape and display distinct girdle bands. In the Netherlands P. spirostriolatum is of occasional occurrence in slightly acidic, mesotrophic moorland pools and fen hollows. Zygospores have been encountered a few times.

Dividing cell of P. spirostriolatum (var. amplificatum) Notice the spiralized striation of the cell wall.

mouse-over: detail

Zygospore of P. spirostriolatum (multifocus composition).


Focus-through video of the cell top of P. spirostriolatum var. amplificatum in apical view showing spiralization of the ridges on the cell wall.