Phylum: Charophyta Family: Closteriaceae
Closterium dianae var. brevius (S.P. Petkoff) Willi Krieger 1935
There are few records of this variety which is thought to be rare in Britain. An acidophile of moorland bogs and pools. It differs from the nominate in being shorter and broader (mainly due to its tumidity), giving an L/B ratio of about 8.
References:
Brook, A.J. & Williamson, D.B. (2010) A Monograph on some British Desmids.