A Beaked Whale Mesoploeen Stranded at Oiso Beach, Japan

Abstract

A beaked whale that belongs to the genus Mesoplodon stranded on 22 Sept. 1957 at Oiso Beach, Sagami Bay, near Tokyo. Skull, vertebral column (C 7 + D 10 + L10 + Ca 21 = 48), and chevrons (11 in number) were collected in a complete set. Four distinctive characters from skull and mandibular are taken into special consideration in classifying the species of Mesoploden, and a key to the species of this genus was summarized basing on these characters. The authors concluded to settle for this specimen a new species and nominated as Mesoploden ginkgodens. The first specimen of Mesoploden from Japan was reported by OGAWA and identified as M. densirostris in 1935. It was examined again in the present work, and identified as the same species to the new specimen, viz. M. ginkgodens. As the space is restricted in this bulletin, the detailed report will be published in the Scientific Reports of the Whales Research Institute No. 13. © 1958, The Japanese Society of Fisheries Science. All rights reserved.