First record of the rare deep-water benthopelagic genus <i>Crassarietellus </i>(Copepoda: Calanoida: Arietellidae) from the high Arctic with the description of a new species <i>Crassarietellus septentrionalis </i>sp.n
A new deep-water benthopelagic copepod species Crassarietellus septentrionalis is described from the Svalbard area in the high Arctic. The new species shares the main characters of the body structure and the morphology of oral parts and swimming legs with the genus Crassarietellus Ohtsuka, Boxshall et Roe, 1994 of the Arietellidae and differs from its congeners in the smaller size, the integument, which is not pitted, some details of the antennule and oral parts armament and the caudal rami seta IV, which is of peculiar swollen shape. An intact male P5 of Crassarietellus septentrionalis sp.n. is herein described for the first time for the genus. The genus Crassarietellus is for the first time recorded in the high Arctic (81°N). This represents the northernmost finding of the genus.