Phylum: Charophyta   Family: Desmidiaceae

Cosmarium bisphaericum var. densegranulatum Grönblad 1920

There are a number of these 'dumbbell-like' cells, which probably comprise a complex. Found in acidic oligotrophic habitats such as shallow vegetated lochans and moorland pools. It's an arctic-alpine species, which is infrequently recorded and thought to be rare. Similar cells can be found under the doubtful C. excavatum f. duplo-maius (see Kouwets 1997, p.44). The Harris finds have been confirmed by Frans Kouwets.

References: 
Kouwets, F.A.C. (1997) Contributions to the Knowledge of the French Desmid Flora I. New and Noteworthy Taxa from the Central and Eastern Pyrenees
Kouwets, F.A.C. (in manuscript) European Flora of the Desmid Genus Cosmarium