Abstract
A new triggerfish, Rhinecanthus abyssus, is described from three specimens collected in the Ryukyu Islands at depths of 120-150 m. It is distinguished from the other species of Rhinecanthus by the combination of the following characters: soft dorsal rays 22-23, soft anal rays 20, a large black blotch around anus, and no semicircular white band on posterior side of body.
