Onisimus turgidus (Sars, 1879) (Amphipoda, Uristidae), an overlooked amphipod from sea anemones in Northern Norway

  • Wim Vader Tromsø Museum, UiT - The Arctic University of Norway, NO 9037 Tromsø
  • Jan Roger Johnsen Ekkerøya, NO 9800 Vadsø
  • Anne Helene S. Tandberg University museum of Bergen, University of Bergen, PO box 78, NO 5020 Bergen https://orcid.org/0000-0003-3470-587X
Keywords: sibling species, Crustacea, species complex


Two Norwegian uristid amphipods, obligate associates of sea anemones, have for a long time been confused sub nomine Onisimus normani Sars, 1890. In reality this species only occurs in south Norway, while the north-Norwegian material belongs to O. turgidus (Sars, 1879), described from the Barents Sea and for a long time forgotten. This paper fully illustrates both species, gives a key, and provides data on their distribution and ecology.


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How to Cite
Vader, W., Johnsen, J. R., & Tandberg, A. H. S. (2020). Onisimus turgidus (Sars, 1879) (Amphipoda, Uristidae), an overlooked amphipod from sea anemones in Northern Norway. European Journal of Taxonomy, 724(1), 34–50. https://doi.org/10.5852/ejt.2020.724.1155
Research article