Oryzomys chacoensis Myers and Carleton, 1981 . Misc. Publ. Mus. Zool. Univ. Michigan, 161:19.

TYPE LOCALITY: Paraguay, Boqueron Dept., 419 km, by road, N.W. of Villa Hayes (along the trans-Chaco Highway) .

DISTRIBUTION: Chaco of Paraguay, Bolivia, Argentina, and S.W. Mato Grosso (Brazil).

COMMENT: Subgenus Oligoryzomys; see Myers and Carleton, 1981:20.