The brown brocket deer is found east of the dry, pre-Andean regions in Argentina and Bolivia, extending to the Atlantic coast on the west; its northern limit is south of the Amazon region and its southern limit includes all of Uruguay and up to the province of Entre Rios in Argentina. Although some authors report its distribution throughout all of Brazil, more recent evidence indicates its substitution by M. nemorivaga in the region of the Amazon (Duarte 1996; Duarte and Jorge 1998; Rossi 2000; Weber and Gonzalez 2003).