Phylum: Charophyta   Family: Closteriaceae

Closterium subscoticum R. Gutwinski 1902

Closely related to Cl. directum but that species is broader with little or no overlap. A feature of Cl. subscoticum is slightly swollen apices giving a capitate appearance. However, cells exist where this feature is not at all obvious.
Cell dimensions: L: 200-290 µm; B: 9.5-12.5 µm; Ap: 6.9-8.0; L/B: 19-30.
A rare species found in slightly to more pronounced acidic condition such as peaty pools, bogs and loch-margins.

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.
Van Westen, M.C. (2024). Sieralgen in Drenthe.