Rattus sordidus (Gould, 1858) . Proc. Zool. Soc. Lond., 1857:242 [1858].

TYPE LOCALITY: Australia, Queensland, open plains Darling Downs = locality of lectotype (see Mahoney and Richardson, 1988) .

DISTRIBUTION: Australia; E coast from the tip of Cape York to NE New South Wales, and some off-shore islands (see Watts and Aslin, 1981:239). New Guinea; lowlands south of Central Cordillera from Dobodura in E Papua New Guinea west and north to Koembe in Irian Jaya (see map in Taylor et al., 1983:265).

SYNONYMS: aramia, brachyrhinus, bunae, conatus, gestri, gestroi, youngi .

COMMENTS: One of the two species of native Rattus in the New Guinea-Australian region that occurs on both land masses. On morphological evidence, Taylor and Horner (1973) arranged villosissimus and colletti as subspecies of R. sordidus . Later evaluations, however, based on chromosomal, biochemical, and hybridization data, suggested the three should be viewed as separate species in the same monophyletic cluster (Baverstock et al., 1977d, 1983a, 1986), which is the way they are treated in current faunal accounts and catalogs (Mahoney and Richardson, 1988; Watts and Aslin, 1981).