We report a new locality for the Brazilian Merganser (Mergus octosetaceus), a critically endangered species from Southern and Central South America. The species’ range is considerably extended to the East, and a new habitat and basin used by the species are given. The species was found near the city of Ouro Preto, Minas Gerais State, Brazil, located in a transition zone between the Cerrado and the Atlantic Forest biomes. Our finding improve a little bit the hope for the conservation of the species but more detailed studies to determine if there is a resident population, or if we recorded a vagrant bird, are necessary.