Notes on the Chelonian Bones Included in an Old Collection of Vertebrate Remains from the Ogido Shell Mound on Okinawajima Island, Japan, with Special Reference to the Soft-shell Turtle Pelodiscus sinensis Reported for That Collection

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Chelonian skeletal remains from the Ogido Shell Mound were examined. Detailed comparisons of the remains with skeletal materials of extant and extinct turtles known from Okinawajima Island and adjacent waters revealed that the Ogido remains do not contain representatives of Pelodiscus sinensis or any other trionychids at all, although recent literature referred to the original excavation report of this shell mound as the only prehistoric record of the soft-shell turtles from the Central Ryukyus. Instead, two of the three bone pieces identified to particular taxa with certainty, were identified to Geoemyda japonica, and the other to a cheloniid species. Discovery of G. japonica from this site further supports the idea that this species, currently confined to the northern part on Okinawajima, had a much broader distribution on this island until recently.