Seven new species of freshwater diatoms (Bacillariophyceae) from the Canadian Arctic Archipelago
Antoniades, Dermot; Hamilton, Paul B.; Hinz, Friedel; Douglas, Marianne S.V. Smol
Seven new species of freshwater diatoms are described from three islands situated along the northern and western margins of the Canadian Arctic Archipelago. The new species are Caloneis fusus, Cavinula vincentii, Cymbopleura venetaeformis, Diadesmis ingeaeformis, Microcostatus turritus, Sellaphora pseudonana and Sellaphora tibia. These species are benthic taxa associated with littoral sediments and mosses. Six of the new species are small forms which are difficult to distinguish in LM and can be rare. The two largest-celled taxa are within genera that have welldocumented species complexes (demes), and in standard LM studies they could not be separated from other related species without the use of SEM. To confirm species differences within the genus Cavinula, Hustedt's type materials for the species C. pseudoscutiformis and C. jaernefeltii were examined. A floristic study of diatoms from freshwater Arctic environments directly related to this work also shows that many more freshwater taxa are present and await further study.