Remarks: The specimen depicted below are in literature often classified as Cosmarium crenatum. The outline of the cells differs from to the original figures of Ralfs and match better with two forms described by Nordstedt as Cosmarium crenatum «Crenae laterales 2» and «Crenae laterales 3» from Svalbard and must be provided with a new taxonomic name. This taxon has three crenations on each side of the semicell and four at the apex. Sometimes a small granule is visible at the basal corner.