Phylum: Charophyta   Family: Desmidiaceae

Cosmarium vexatum var. lacustre Messikommer 1935

Cosmarium vexatum is regarded as a doubtful species and Kouwets (in manuscript) is proposing to rename this taxon as a reclassified species. Because of taxonomic confusion, distribution is unclear. It would seem to prefer slightly acidic condition.

References: 
Messikommer, E. (1935) Die Algenwelt der innern Plessuralpen.
Kouwets, F.A.C. (in manuscript) European Flora of the Desmid Genus Cosmarium.