Phylum: Charophyta   Family: Closteriaceae

Closterium littorale F. Gay 1884

First described by Gay (1884: 339). Recent finds have been with filamentous algae and cyanobacteria in flowing water. Brook & Williamson (2010: 262) specifically mention: “It also occurs attached to macrophytes and associated with other algae, in rivers.”
Cell dimensions: L: 97-200 µm; B: 11-20 µm; Ap: 2.5-5.0 µm; L/B: 8.5-12.
A rare species that, apart from flowing water, also occurs in lochs and pools.

References: 
Brook, A.J. & Williamson, D.B. (2010). A Monograph on some British Desmids.
Coesel, P.F.M. & Meesters, K.J. (2023 second edition). Desmids of the Lowlands.
Gay, F. (1884). Essai d'une monographie locale des Conjugées.