부산대학교 도서관

Longman's beaked whale (Indopacetus pacificus) is one of the least known cetaceans in the world. Since it was first described as its own species in 1926, they have been observed alive at sea only on a few occasions, and stranding has been reported for less than 20 cases worldwide to date. Thus, biological information regarding this species is still very limited compared to other cetaceans. In this study, the external appearance, osteological characters, DNA analysis, and parasitic organisms of a Longman's beaked whale that was stranded on Ukibaru Island in Okinawa, Japan, are reported. The external appearance and the osteological features of the specimen matched the features of the Longman's beaked whale presented in previous studies. MtDNA control-region sequences obtained from the specimen also matched the reference sequences of the species deposited in GenBank. Based on these features, we concluded that the specimen was a Longman's beaked whale. The specimen was estimated as a juvenile male because of its body length (4.78 m), no eruption of teeth on its lower jaw, and no fusion of the vertebral epiphyses of its vertebral bodies. Whale lice collected from the body surface of the specimen were identified as Isocyamus indopacetus, which are known to parasitize Longman's beaked whales. This was the first record of a stranded Longman's beaked whale in Okinawa and also the first record of a juvenile male for this species confirmed in Japan. The whole skeleton was cataloged in the collection of the Okinawa Churashima Research Center (Okinawa Churashima Foundation). Key Words: Longman's beaked whale, Indopacetus pacificus, external appearance, osteology, genetic analysis, whale lice, Isocyamus indopacetus
Introduction Longman's beaked whale (Indopacetus pacificus) is one of the least known cetaceans in the world. It was first described as a member of the genus Mesoplodon by Longman (1926) [...]