Phylum: Charophyta Family: Desmidiaceae
Staurastrum crassangulatum Coesel
A benthic and planktonic species in circumneutral waters. Not thought to be scarce but distribution is vague
References:
Coesel, P.F.M. & Meesters, K.J. (2013) European Flora of the Desmid Genera Staurastrum and Staurodesmus