Phylum: Charophyta   Family: Desmidiaceae

Cosmarium sp. Geirinish 

Appearing on the periphery there are single, relatively large granules combined with a series of seemingly vertical ridges in the semicell’s centre, as noted in the live cell. However, in the empty semicell the central protuberance shows up as a series of separate granules. There is superficial resemblance to C. subpunctulatum but the cells are more depressed in the taxon in question.
Cell dimensions: L: 39.2 µm; B: 37.2-37.8 µm; Is: 14.2 µm; Th: 22.7-24 µm; L/B: 1.04-1.06.
Found in circumneutral flood-water on machair.

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