Micrasterias radiosa. Notice that the upper lateral semicell lobes of the first order are divided to a higher order than the lower ones.

Cell dimensions (L x B): ca 160 x 150 µm



Desmid of the month
January 2014

Micrasterias radiosa*

Micrasterias radiosa is affiliated** to M. papillifera. As compared to the latter species, lateral semicell lobes in M. radiosa are divided to a higher order. Moreover, invaginations of those lobes are deeper and wider resulting in more slender lobules, often with an undulate margin. In the Netherlands, M. radiosa is of very rare occurrence and only known from some oligo-mesotrophic moorland pools in the southern part of the country. 

* Synonym: Micrasterias sol, in flora West & West (1905)

** The mutual relationship of M. radiosa and M. papillifera appears from the occurrence of transitional forms (formally described as M. radiosa var. murrayi and M. papillifera var. pseudomurrayi).

Dividing cell of M. radiosa. Notice wide invaginations of the cell wall.