Phylum: Chlorophyta   Family: Hydrodictyaceae

Pseudopediastrum boryanum (P.J.F. Turpin) E. Hegewald 2005

First described and illustrated by Turpin (1828: 319, pl. 13: 22) as Helierella boryana. More recently, it has been renamed by Hegewald (2005: 1052).
Coenobia spherical with 25-180 cells: diameters: 20-27 µm. Marginal cells: 8-30 µm across.
Common in lochs, ponds, etc. Considered an indicator of mildly enriched waters.

References: 
Hegewald, E. [in] Buchheim, M. et al. (2005). Phylogeny of the Hydrodictyaceae (Chlorophyceae): inferences from rDNA data.
John, D.M., Whitton, B.A. & Brook, A.J. (2011 second edition). The Freshwater Algal Flora of the British Isles.
Turpin, P.J.F. (1828). De la description de plusieurs genres et espèces nouvelles très remarquables, découverte parmi les productions végétales et microscopiques.