Phylum: Charophyta   Family: Desmidiaceae

Cosmarium kinhemense F.A.C. Kouwets 2025

A small cell with the semicells hexagonal, sinuses linear and closed. Lower part of the sides divergent and retuse, upper half markedly convergent and concave, side angle quite broadly rounded. Apices truncate and retuse. Cell-wall smooth, apical view with a slightly swelling. Chloroplast axile with a central pyrenoid.
Single cell dimensions: L: 15.9-17.31 µm; B: 12.3-13.2 µm; Is: 4.3-4.5 µm; Th: c.7-9 µm; L/B: 1.30-1.32.
Dutch material has be found occurring atmophytically on wet sand. The Outer Hebridean finds (confirmed by Frans Kouwets) were from a shallow, acidic, boggy pool.

References: 
Kouwets, F.A.C. (2025). European Flora of the Desmid Genus Cosmarium. Part 1: Text. Part 2: Plates.