The earliest fossil record of the bandicoot rat (Bandicota indica) from the early Middle Pleistocene of Taiwan with discussion on the Quaternary history of the species

摘要

Three molar fossils of murine rodents were newly discovered from an outcrop in the Tsailiao area of Tainan City, ROC. They were dated to the early Middle Pleistocene (ca. 0.7 Ma) based on the stratigraphic and chronological data for the layers distributed at and around the outcrop. A detailed systematic analysis of the fossils reliably referred them to Bandicota indica. This species is now distributed widely in the Oriental Region, including Taiwan, where it usually lives in human-associated environments. Therefore, it is generally believed that this species was introduced artificially into Taiwan very recently. However, the fossils demonstrate that B. indica inhabited Taiwan in the early Middle Pleistocene. They also imply that this species has inhabited Taiwan continuously since the early Middle Pleistocene, although this inference must be tested with nonmorphological methods. The literature on the fossil record of Bandicota was examined to understand its chronospatial distribution throughout the Oriental Region, and indicates that the fossils from the Tsailiao area represent the earliest record of B. indica. The history of the species is discussed on the basis of these data.