Phylum: Heterokontophyta   Family: Sciadiaceae

Ophiocytium cochleare (K.E. Eichwald) A. Braun 1855

First described and illustrated by Eichwald (1847: 301; pl. 8: 4) as Spirodiscus cochlearis. It was later moved to its current position by (Braun 1855: 54). A coiled alga that has a prominent spine at one end and a swollen base at the other, occasionally also with a short spine.
Cell dimensions: L: 10-500 µm; B: 5-9 µm.
Fairly common in moorland pools and bogs.

References: 
Braun, A. (1855) Algarum unicellularium genera nova et minus cognita praemissis observationibus de algis unicellularibus in genere.
Eichwald, K.E. (1847) Erster Nachtrag zur Infusorienkunde Russlands.
John, D.M., Whitton, B.A. & Brook, A.J. (2011 second edition) The Freshwater Algal Flora of the British Isles.