Phylum: Charophyta Family: Desmidiaceae
Cosmarium sp. (02)
This unidentified species has some affinity with Cosmarium tinctum in terms of size, general shape, and the cell wall being generally coloured yellowish- to reddish-brown due to incrustation with iron salts. It differs in having a closed sinus from the isthmus and, for the most part, distinctly retuse apices. The habitat is acidic moorland bogs and pools, especially with Sphagnum. Two populations have now been found which are remarkably consistant in size, shape and colour. I'm grateful to Frans Kouwets for helpful comments
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