The first Japanese record of mammalian tridactyl fossil footprints is reported from the Plio-Pleistocene Kobiwako Group at two sites: Otsu City, Shiga Prefecture and Iga City, Mie Prefecture, Japan. The first site, Ikadachi-mukouzaichi, Otsu City, is the Middle Pleistocene Katata Formation, the uppermost horizon of the Kobiwako Group, and the second site, at Midoro, Iga Ciry, is the Pliocene Iga Formation, the lowest horizon of the Group.
Comparisons with the footprints and sole shape of extant rhinocerotids and tapiroids indicates that these fossils are identifiable as rhinocerotids, based on morphological characters of the front hoof, the third toe tip, and the posterior margin. This type of footprint is reported from the Pliocene and the Middle Pleistocene of Japan for the first time, although several rhinocerotid molars and postcranial elements have previously been described from these ages.
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