New and previously known species of Copepoda and Cladocera (Crustacea) from Svalbard, Norway – who are they and where do they come from?

Arctic landscapes are characterised by an immense number of fresh and brackish water habitats – lakes, ponds and puddles. Due to a rather harsh environment, there is a limited number of species inhabiting these ecosystems. Recent climate-driven regime shifts impact and change Arctic biological communities. New species may appear, and existing communities may become supressed or even disappear, depending on how ongoing changes match their ecological needs. This study provides data on presently existing and probably recently arrived fresh and brackish water microcrustacean species in the Norwegian High Arctic - Svalbard archipelago. The study focused on two taxonomic groups, Cladocera and Copepoda and altogether we found seven taxa new for Svalbard: Alona werestschagini, Polyphemus pediculus, Diaptomus sp., Diacyclops abyssicola, Nitokra spinipes, Epactophanes richardi and Geeopsis incisipes. Compared with an existing overview for the area, our study increased the number of species by more than 20 %, and some of the new species have never been found that far north. Finally, we present a complete and critically updated revised species list of fresh and brackish water cladocerans and copepods for Svalbard.