A new species of Arenallianassa (Decapoda: Axiidea: Callianassidae) from hydrothermal vents with notes on its ecology and a redescription of Arenallianassa arenosa (Poore, 1975)

The hitherto monotypic genus Arenallianassa Poore, Dworschak, Robles, Mantelatto and Felder, 2019 is revised following the discovery of a new species, Arenallianassa katrinae sp. nov. from New Zealand and Tonga. The original description of the type species Arenallianassa arenosa (Poore, 1975) is augmented. The new species has been found in localised high abundance in the vicinity of shallow (111–181 m depth) hydrothermal vents at each end of the Kermadec–Tonga Volcanic Arc system. This brings the number of callianassoids in New Zealand to six.