Phylum: Charophyta   Family: Desmidiaceae

Staurastrum aculeatum G. Meneghini ex J. Ralfs 1848

First described by Meneghini and illustrated by Jenner in Ralfs (1848: 142, pl. 23: 2). Cells slightly broader than long, extravagantly ornamented with simple and compound spines.
Cell dimensions: L: 45-61 µm; B: 48-70 µm; Is: 16-18.5 µm; L/B: 0.87-0.98.
Found in acidic habitats such as moorland pools and bogs. It has a wide geographical distribution but never common.

References: 
Coesel, P.F.M. & Meesters, K.J. (2013) European Flora of the Desmid Genera Staurastrum and Staurodesmus.
Ralfs, J. (1848) The British Desmidieae.
West, W., West, G.S. & Carter, N. (1923) A Monograph of the British Desmidiaceae, Volume 5.