Rattus lugens (Miller, 1903) . Smithson. Mise. Coll., 45:33.

TYPE LOCALITY: Indonesia, Kepulauan Mentawai, Pulau Utara Pagai (North Pagai Isl) .

DISTRIBUTION: Islands of Siberut, Sipora, Pagai Utara, and Pagai Selattan in the Mentawai Archipelago off coast of SW Sumatra; these islands lie on a slender peninsula of the continental shelf.

SYNONYMS: mentawai.

COMMENTS: Chasen (1940) listed lugens and mentawai each as a subspecies of R. rattus, but the Mentawai endemic is a morphologically distinctive species closely related to R. adustus from Enggano Isl, and to the R. tiomanicus complex (Musser, 1986; Musser and Califia, 1982; Musser and Heaney, 1985). Part of the rodent fauna endemic to Mentawi Archipelago (see account of Leopoldamys siporanus).