Phylum: Charophyta   Family: Desmidiaceae

Staurastrum striolatum (C. Nägeli) W. Archer 1861

Semicells are close to rhombic with truncate processes and predominantly triradiate with concave sides when viewed apically. It closely resembles S. alternans, but that species has slightly shorted processes that are more rounded, it also has a short isthmus. It also resembles S. dilatatum but that species appears stockier being predominantly 4-radiate. The zygospores of this complex are virtually identical.
Cell dimensions: L: 21-30 µm; B: 20-36 µm; Is: 7-8.2 µm.
Found in slightly acidic to weakly alkaline waters in mesotrophic habitats such as moorland pools and loch-margins. It’s rarely recorded.

References: 
Coesel, P.F.M. & Meesters, K.J. (2013). European Flora of the Desmid Genera Staurastrum and Staurodesmus.
Van Westen, M.C. (2024). Sieralgen in Drenthe.