Phylum: Dinoflagellata   Family: Peridiniaceae

Peridinium cinctum (O.F. Müller) C.G. Ehrenberg 1832

First described and illustrated by Müller (1773: 98) as Vorticella cincta. It was later moved by Ehrenberg (1832: 74) to its current position. A widespread and common species found in the plankton of pools, lochs and ditches.

References: 
Ehrenberg, C.G.(1832) Über die Entwickelung und Lebensdauer der Infusionsthiere; nebst ferneren Beiträgen zu einer Vergleichung ihrer organischen Systeme.
John, D.M., Whitton, B.A. & Brook, A.J. (2011 second edition) The Freshwater Algal Flora of the British Isles.
Müller, O.F. (1786) Animalcula infusoria fluviatilia et marina quæ detexit, systematice descripsit et ad vivum delineari curavit Otho Fridericus Müller ; sistet opus hoc posthumum, quod cum tabulis Aeneis L. in lucem tradit vidua ejus nobilissima cura Othonis Fabricii.