Phylum: Charophyta   Family: Desmidiaceae

Cosmarium regnellii var. kerguelense Willi Krieger & Gerloff 1969

Cosmarium regnellii is a complex with many varieties and forms. This variety by Willi Krieger & Gerloff (1969: p.246, pl. 43: 5) represents the larger end of the range. Coesel (1979: p. 391, pl. 15: 35-37) dscribes it as "Common in tychoplankton of pools and ditches." This is the first record from the Outer Hebrides and represents a different habitat from mosses on dripping rocks.

References: 
Krieger, W. & Gerloff, J. (1962-9) Die Gattung Cosmarium.
Coesel, P.F.M. (1979) Desmids of the broads area of N.W.-Overijssel (The Netherlands) II.
Kouwets, F.A.C. (in manuscript) European Flora of the Desmid Genus Cosmarium.