Phylum: Charophyta   Family: Mesotaeniaceae

Mesotaenium degreyi var. breve sensu lato  West

Mesotaenium degreyi and its varieties and forms seem scarce if not rare. Found in ephemeral moorland depressions and from dripping rocks. The specimens depicted have the length of var. breve and the width of forma major as descibed by West & West (1904). Brook and Williamson (2010) also found populations in Ireland that didn't conform to either suggesting a variable complex. Based on the Wests' quotients: 2.5 for breve and 4 for major, the current samples alines best with the former

References: 
West, W. & West, G.S. (1904) A Monograph of the British Desmidiaceae, Volume 1
Brook, A.J. & Williamson, D.B. (2010) A Monograph on some British Desmids