Phylum: Charophyta   Family: Desmidiaceae

Micrasterias jenneri  Ralfs

Widespread in acidic moorland pools and peat cuttings but infrequently recorded in the Outer Hebrides

References: 
West, W. & West, G.S. (1905) A Monograph of the British Desmidiaceae, Volume 2
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