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The Longman’s beaked whale (Indopacetus pacificus) is one of the rarest cetaceans worldwide. Since it was first described as its own species in 1926, they have been observed alive at sea on several occasions, and less than 20 strandings have been reported worldwide to date. Thus, basic information regarding this species, such as the maximum size of adult individuals or body length at birth, remains unknown. In this study, the external appearance and DNA analysis of a female Longman’s beaked whale stranded on Miyako Island, Okinawa, Japan, are reported. The external appearance of the specimen matched the features of the Longman’s beaked whale presented in previous studies. The mitochondrial DNA control-region sequences obtained from the specimen also matched the reference sequences of the species deposited in GenBank. Based on these features, the specimen was confirmed as a Longman’s beaked whale. The specimen was estimated to be neonate because of its body length (235 cm) and the clear several fetal folds observed on its body surface. To the best of our knowledge, this is the first report of a confirmed new born neonate of Longman’s beaked whale in the world.

Gobioid larvae collected from the coast of Okinawa Island, southern Japan, were identified on the basis of a combination of morphological characters and a sequence of a hypervariable region of mitochondrial 12S ribosomal RNA (12S rRNA) gene (138–145 base pairs). A short-term formalin fixation technique enabled identification using both morphological and genetic methods. Thirteen of the 21 types of gobioid larvae assessed were identified to the species level. Additionally, we described the morphology of the postflexion larvae of wormfish Paragunnellichthys sp. and shrimp-associated goby Ctenogobiops feroculus, identified for the first time in their respective genera.

Ram ventilation, which is characterized by the production of a respiratory water current over the gill by locomotory effort, widely occurs among pelagic sharks. However, the process by which the juvenile starts this respiratory mechanism remains largely unknown. The captive birth of a Tiger Shark (Galeocerdo cuvier) at the Okinawa Churaumi Aquarium on 23 March 2017 permitted the examination of the parturition process and behavior of newborn juveniles of this species. Sonographic examination of the pregnant female showed that, unlike adult Tiger Sharks, embryos used buccal pumping, revealing that Tiger Shark shifts its respiratory mechanism from buccal pumping to ram ventilation after birth. Our observation also showed that ram ventilation of the neonate was not continuous, and buccal pumping was also used when the neonate intermittently rested on the bottom of the tank. We speculate that this behavior is the transitional phase in the shift from buccal pumping to ram ventilation in neonates, and continuous ram ventilation may be established after the development of continuous and fast swimming abilities.