Berylmys Ellerman, 1947 . Proc. Zool. Soc. Lond., 117:261.

TYPE SPECIES: Epimys manipulus Thomas, 1916 .

COMMENTS: Originally proposed as a subgenus of Rattus by Ellerman (1947-1948), but elevated to generic rank in a revision by Musser and Newcomb (1983) which recorded taxonomic history of names and groups associated with Berylmys, and reported past evolutionary histories of species (which have been centered in Indochina), finding that Berylmys was dentally similar to Niviventer, Maxomys, and Leopoldamys, but shared some derived cranial characters with Rattus and that phylogenetic relationships were still unknown. Sperm morphology united Berylmys with Sundamys, Rattus, and Leopoldamys (Breed and Yong, 1986), but that union was based on a shared spermatozoal form which is probably primitive.