Biogeography of Living Mammals in the Ryukyu Islands.

Abstract

The faunas of the living non-volant mammals in the Ryukyu Islands are geographically different among northern, central and southern islands, and the Senkaku Group. The Tokara Gap and the Kerama Gap are recognized as important borders of distributional ranges. The northern Ryukyu species are the same as those on the main-islands of Japan; probably they have been isolated only since the late Pleistocene. The central Ryukyu species include endemic elements that are considered as Miocene immigrants. The southern Ryukyu Islands has one endemic species, Prionailurus iriomotensis, which was possibly derived from the ancestral form of P. bengalensis in the middle Pleistocene. The Senkaku Group has two species, of which Nesoscaptor uchidai is endemic to this island group at the generic level. This mole may be closely related to Mogera insularis in Taiwan. The second species, Apodemus agrarius, is a continental species and probably immigrated in the late Pleistocene.