Revision of the Tubenose Poacher Genus Pallasina Cramer (Perciformes: Cottoidei: Agonidae)

Abstract

Species of the tubenose poacher genus Pallasina are assessed following examination of over 450 specimens from throughout the Pacific Rim, from the coast of California to the Chukchi Sea and Sea of Japan. The results presented here, including both morphological and mitochondrial DNA datasets, indicate that three species of Pallasina occur in the North Pacific and surrounding seas. Pallasina aix is found in the eastern North Pacific from California to southeast Alaska and in the Salish Sea. It has the shortest barbel of the three species and a unique haplotype in the mitochondrial COI region. Pallasina barbata is the most widespread species, ranging from the Gulf of Alaska to the Chukchi Sea and west to northern Japan. It is distinguished by having a moderate barbel length and can be separated from the other two species using a variety of meristic characters. Pallasina eryngia is found only in the central and northern Japanese Archipelago, and it is a relatively deep-water species. It is distinguished by having a long barbel, as well as relatively high counts of vertebrae and dermal plates. This study presents redescriptions of all three species and a key to their identification.