Phylum: Charophyta   Family: Desmidiaceae

Cosmarium sphagnicola West & G.S. West 1897

Common in moorland peaty pools and bogs, often with Sphagnum, sometimes in large numbers. It can be confused with similar species though.

References: 
West, W. & West, G.S. (1908) A Monograph of the British Desmidiaceae, Volume 3
John, D.M. & Williamson, D.B. (2009) A Practical Guide to the Desmids of the West of Ireland
Coesel, P.F.M. & Meesters, K.J. (2007) Mesotaeniaceae and Desmidiaceae of the European Lowlands