Phylum: Charophyta Family: Desmidiaceae
Staurastrum aculeatum Meneghini ex Ralfs
Found in acidic habitats such as moorland pools and bogs. It has a wide geographical distribution but never common.
References:
Ralfs, J. (1848) The British Desmidieae
West, W., West, G.S. & Carter, N. (1923) A Monograph of the British Desmidiaceae, Volume 5
Coesel, P.F.M. & Meesters, K.J. (2013) European Flora of the Desmid Genera Staurastrum and Staurodesmus