Rattus simalurensis (Miller, 1903) . Proc. U.S. Natl. Mus., 26:458.

TYPE LOCALITY: Indonesia, Sumatra, Pulau Simeulue (Simalur) .

DISTRIBUTION: Simalur Isl and nearby islands of Siumat, Lasia, and Babi.

SYNONYMS: babi, lasiae (see Musser and Heaney, 1985).

COMMENTS: The form simalurensis and its two synonyms were each listed as a separate subspecies of R. rattus by Chasen (1940), but simalurensis is distinct from R. rattus and in morphology represents slightly larger-bodied island variants of R. tiomanicus (Musser, 1986; Musser and Califia, 1982; Musser and Heaney, 1985). Whether populations on Simalur islands are distinct species or insular representatives of R. tiomanicus occurring off the margin of the continental shelf will have to be determined by systematic revision of the R. tiomanicus complex.