Phylum: Charophyta   Family: Desmidiaceae

Cosmarium sportella var. subnudum West & G.S. West 1908

West & West (1908, p. 186, pl. 82:14) have it as "… abundant among mosses on dripping rocks." This is the situation in the Outer Hebrides and can be described as locally common in this habitat. It has also been found in slightly acidic, mesotrophic, loch-margins.

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