Desmid of the month
Like in Cylindrocystis brebissonii cells of Cylindrocystis gracilis are
cylindric in shape with broadly rounded ends. However, whereas the chloroplasts
in C. brebissonii are provided with ridges that, from a central core,
radiate in all directions, the chloroplast ridges in C. gracilis run
more or less parallel in a longitudinal direction. Cylndrocystis gracilis was described by Ilse Hirn (1953). As an additional diagnostic characteristic
(against C. brebissonii) she found a different stainability of cell sap
when treated with specific dyes. In the Netherlands C. gracilis is
locally of abundant occurrence in (semi)emersed Sphagnum vegetation.
Hirn, I., 1953.
Vitalfärbungsstudien an Desmidiaceen. — Flora 140: 453-473.
Image © RIZA (mouseover)
of Cylindrocystis gracilis (in different focus). Notice the longitudinal
dimensions (L x B): 40 x 13 µm.