Phylum: Charophyta   Family: Desmidiaceae

Cosmarium tyrolicum var. beanlandii (West & G.S. West) Willi Krieger & Gerloff 1962

A rare desmid found in Ireland and the Outer Hebrides. More finds are needed to get a better geographical perspective but the Atlantic north-west would appear to be its stronghold. A main characteristic is the crenate lateral sides as seen in face-view: these traverse the sides. Found in moorland peaty pools and quaking Sphagnum bogs.

References: 
John, D.M. & Williamson, D.B. (2009) A Practical Guide to the Desmids of the West of Ireland.
Kouwets, F.A.C. (in manuscript) European Flora of the Desmid Genus Cosmarium.