A new species of Aspidophryxus G.O. Sars, 1883 (Crustacea, Isopoda, Dajidae) from Caribbean mysid shrimp.

A new species of dajid isopod in the genus Aspidophryxus G.O. Sars, 1883 is described from three females and one male found infesting the lateral carapace of Heteromysis (Olivemysis) actiniae Clarke, 1955 (Mysidae: Heteromysinae) associated with the corkscrew anemone Bartholomea annulata (Lesuer, 1817) (Anthozoa: Aiptasiidae) from the British Virgin Islands. This is the first record of the genus from the western Atlantic; three other species are known from northern European waters, the central Atlantic and Japan, all on mysid hosts. The new species is the first dajid recorded from tropical Caribbean waters. A key to species in the genus and a list of all known hosts with parasite orientation are provided.