Melomys lanosus Thomas, 1922 . Ann. Mag. Nat. Hist. ser. 9, 9:263.

TYPE LOCALITY: New Guinea, Irian Jaya, Doormanpad-bivak (3°30'S, 138°30'E), 2400 m .

DISTRIBUTION: Mountain forests (not recorded below 1500 m) of N New Guinea; from the type locality in Irian Jaya eastward along Central Cordillera through the Telefomin region, Schrader Range, Kratke Mts, and Mt Hagen region to the Wau area of Papua New Guinea; also from Cyclops Range in the N coastal mts; not known from Huon Peninsula.

SYNONYMS: shawmayeri .

COMMENTS: Once treated as a subspecies of M. levipes, lanosus, as Flannery (1990b:230) noted, is a separate species. It is unrelated to M. levipes, but instead is phylogenetically allied with M. rattoides, a larger-bodied species that displaces it in lower altitudes. This close association was also reflected in Menzies' (1990) similarity coefficient analysis. Our study of specimens in the American Museum of Natural History revealed that Melomys lanosus and M. rattoides share derived traits (only one pair of teats, and the derived cephalic arterial circulation and its osseous reflection in the cranium; see figures in Musser and Heaney, 1992) not found in any other species of Melomys . Any systematic revision of Melomys will have to determine whether these two species are members of that genus, which seems unlikely. Flannery listed shawmayeri as a synonym of M. rattoides, but holotype is example of M. lanosus .