Two New Species of Halmaheramys (Murinae: Rattini) from Archaeological Deposits on Morotai Island, North Moluccas, Indonesia

Two new species of murine rodents (Halmaheramys funderus sp. nov. and H. bellwoodi sp. nov.) are described from remains in an archaeological site on Morotai Island in North Maluku (Maluku Utara) Province of Indonesia. Both species are approximately the same size, (about the size of a Norway or brown rat, Rattus norvegicus) but they differ from each other in the degree of elongation of the snout and in molar size relative to osseous structures. These morphological contrasts are suggestive of dietary differences. Both species survived into the Holocene, and because the modern mammal fauna of Morotai is very little studied, it is possible that these species may still be extant on the island. Recognition of these taxa helps to demonstrate the distinctive nature of the Morotai murine fauna, which has unique species of Rattus and Halmaheramys compared to Halmahera-Bacan on one hand, and to Obi-Bisa on the other. The subfossil record (and modern fauna) of Morotai also lacks other Australo-Papuan genera that characterize other North Moluccan islands, such as Hydromys and Uromys (known from Obi) and Melomys (known from Halmahera and Obi-Bisa).