A review ofLeptocarisincluding a description ofL. ryukyuensissp. nov. (Copepoda: Harpacticoida: Darcythompsoniidae)

Abstract

We provide a review on scientific contributions concerned withLeptocaris(Harpacticoida: Copepoda) that includes the zoogeography, ecology, biology, and morphology of this genus. A tabular key is given to aid in the identification of theignavus-group.Leptocaris ryukyuensissp. nov. is included on the basis of specimens collected from Akeijima sandy beach of the Ryukyu Islands in Japan. The new species can be distinguished from its congeners by an abexopodal seta and 3 exopodal setae on A2, a barbed inner seta on the proximal, endopodal segment of female P1 to P3, setae of the caudal ramus (setae I and II are very small, and the basal seta is transformed to a big spine), and modified inner setules of P2 enp-2 and P3 enp-2 in the males. The new species belongs to theignavus-group established by Kunz (1994) and is the third species of the genusLeptocarisin East Asia.