A new species of the chirostylid squat lobster genus Uroptychus Henderson, 1888 (Decapoda: Anomura: Chirostylidae) from the Hoei Seamount, Nishi-Shichito Ridge, Northwest Pacific off Japan

A new species of the chirostylid squat lobster, Uroptychus roseus sp. nov., is described based on two specimens (heterosexual pair) from the Hoei Seamount in the Nishi-Shichito Ridge, Northwest Pacific off Japan, at a depth of 2179 m. The specimens were associated with a colony of an unidentified chrysogorgiid coral. It closely resembles U. orientalis Baba & Lin, 2008 and U. occidentalis Faxon, 1893, but is distinguished by the shape of the thoracic sternite, the short, terminally blunt antennal acicle, and less developed denticles on the crista dentata on the third maxilliped ischium.

The discovery of the present new species raises the number of species of Uroptychus known from Japan to 17. Also, U. roseus sp. nov. is the seventh of the name species of the genus inhabiting the depth greater than 2000 m. Sequences of the mitochondrial COI and 16S rRNA genes of the new species are provided.