Palaemonella hachijo, a new species of shrimp (Crustacea : Decapoda : Palaemonidae) from a submarine cave in southern Japan

A new species of the pontoniine shrimp genus Palaemonella Dana, P. hachijo, is described and illustrated on the basis of single male specimen from a s ubmarine cave at Hachijo-jima Island, Izu Islands, southern Japan. It close ly resembles P. dolichodactylus Bruce, but is readily distinguished by the antennal spine overreaching the distal margin of the antennal basicerite, t he posteroventral margin of the fifth abdominal somite armed with an acute tooth, and the ambulatory propodi not segmented.