Phylum: Charophyta   Family: Closteriaceae

Closterium moniliferum var. submoniliferum  (Woronchin) Willi Krieger

This variety is still accepted taxonomically based purely on the disposition of the pyrenoids which are irregular. The type species has the pyrenoids in a central line. However, this is a variable character of doubtful taxonomic value. Although found in waters with a wide pH range, it favours neutral to slightly alkaline

References: 
Brook, A.J. & Williamson, D.B. (2010) A Monograph on some British Desmids
Coesel, P.F.M. & Meesters, K.J. (2007) Mesotaeniaceae and Desmidiaceae of the European Lowlands
Ruzicka, J. (1977) Die Desmidiaceen Mitteleuropas, Volume 1, Part 1