Phylum: Charophyta Family: Desmidiaceae
Cosmarium bioculatiforme F.A.C. Kouwets
This is a proposed new name by Kouwets (in manuscript) but it will have no authenticity until published but I will leave it here for reference. He notes: 'This form had been previously listed and figured under C. cf bioculatum in Kouwets (2001). The open, acute-angled sinus is a key character. The author has kindly identified this proposed species for me
References:
Kouwets, F.A.C. (in manuscript) European Flora of the Desmid Genus Cosmarium
Kouwets, F.A.C. (2001) Contributions to the knowledge of the French desmid flora 3. New and rare taxa from the regions of Dordogne and Limousin