Revision of the Western North Pacific Species of the Genus Raja

Abstract

Comparison of a sizable material of the genus Raja from the western North Pacific with the type specimens of almost all the nominal species in the area revealed a new species, Raja (Okamejei) boesemani. Among the western North Pacific Raja (Okamejei) , the new species shows the closest resemblance to R.(O.) hollandi Jordan et Richardson. The new species, however, differs from R.(O.) hollandi mainly in having a relatively narrow interdorsal distance, rosette-like color patches of the disc and a pair of dark rings at the pectoral axils. The comparison also re-vealed that there were a total of five Raja (Dipturus) and six Raja (Okamejei) species in the western North Pacific. A revised key is given to the species also including the eastern North Pacific Raja (Dipturus) species, R. binoculata Girard and R. rhina Jordan et Gilbert.