Phylum: Charophyta Family: Closteriaceae
Closterium dianae var. pseudodianae (J. Roy) Willi Krieger 1935
According to Kreiger's (1935) drawings, the degree of arc can be shallow or quite considerable with cells showing some tumidity on the ventral side. Found in mesotrophic boggy pools.
References:
Krieger, W. (1935). Die Desmidiaceen Europas mit Berücksichtigung der aussereuropäischen Arten. Teil 1, Lieferung 2.
Brook, A.J. & Williamson, D.B. (2010) A Monograph on some British Desmids.
Coesel, P.F.M. & Meesters, K.J. (2007) Mesotaeniaceae and Desmidiaceae of the European Lowlands.