Phylum: Dinoflagellata   Family: Peridiniaceae

Peridinium willei H. Huitfeldt-Kaas 1900

First described and illustrated by Huitfeldt-Kaas (1900: 5, figs 6-9). A worldwide distribution and common in the plankton of moorland pools, lochs, and bogs.

References: 
Huitfeldt-Kaas, H. (1901) Die limnetischen Peridineen in norwegischen Binnenseen.
John, D.M., Whitton, B.A. & Brook, A.J. (2011 second edition) The Freshwater Algal Flora of the British Isles.