Phylum: Heterokontophyta   Family: Goniochloridaceae

Pseudostaurastrum enorme (J. Ralfs) R. Chodat 1921

First described by Ralfs (1848: 140, pl. 33: 11) and illustrated by Jenner as Staurastrum enorme. It was much later moved from the desmid genus to its current position by Chodat (1921: 304). John et al. (2011: 332) described it thus: “Irregularly tetrahedral or polyhedral, with a stout central body and short thick bifurcating arms ending in 5-10 µm long spines; ...”.
Cell diameters: 25-45 µm.
Commonly found in the phytoplankton and marginal vegetation in moorland pools and shallow bogs.

References: 
Chodat, R. (1921) Algues de la région du Grand St-Bernard. I. Algues rares ou nouvelles du Plan de Jupiter. II. Sur la place à attribuer aux genres Tetraedron et Polyedrium.
John, D.M., Whitton, B.A. & Brook, A.J. (2011 second edition) The Freshwater Algal Flora of the British Isles.
Ralfs, J. (1848) The British Desmidieae.