Review of Japanese Jawfishes of the Genus Opistognathus (Opistognathidae) with Description of Two New Species

Abstract

Two new jawfishes, Opistognathus decorus and O.liturus are described from Okinawa and Shirahama-cho, Wakayama Prefecture, respectively.They are readily distinguished from all other species of Opistognathus having 11 or 12 segmented dorsal fin rays by the possession of prominent, irregular dark blotches on the head.Opistognathus decorus differs from O.liturus most notably in having more gill rakers on the first gill arch, 41-44 (versus 31), smaller orbit diameter, 7.9-9.0% SL (vs.12.3), wider bony interorbital, 3.8-4.3% SL (vs.1.9), fewer cephalic sensory pores and differently shaped infraorbital bones.A key, diagnoses and synonymies are given for all Japanese species of Opistognathus.