Phylum: Chlorophyta   Family: Oocystaceae

Eremosphaera viridis A. De Bary 1858

First described and illustrated by De Bary (1858: 56, pl. 8: 26-27). A large alga that can be found singly or in 2 or 4 celled coenobia.
Cell diameters: 30-150 µm.
Mainly reported from acidic waters but has also been found in circum-neutral habitats.

References: 
De Bary, A. (1858) Untersuchungen über die Familie der Conjugaten (Zygnemeen und Desmidieen) Ein Beitrag zur physiologischen und beschreibenden Botanik.
John, D.M., Whitton, B.A. & Brook, A.J. (2011 second edition) The Freshwater Algal Flora of the British Isles.