New records of the rare little rufous mouse opossum, Marmosa lepida (Thomas,1888) (Mammalia, Didelphidae) in southeastern Amazonia, Brazil

Here we present new records of the mouse opossum Marmosa (Stegomamosa) lepida (Thomas, 1888) collected in the recently flooded region of the Xingu River during the construction of the Belo Monte hydropower dam in the state of Pará, Brazil. This taxon is rarely captured, and it has often been misidentified as other similar genera of arboreal marsupials, such as Gracilinanus. Our specimens were identified morphologically and genetically using partial DNA of the mitochondrial cytochrome b gene. The new records increase the known distribution by about 250 km to the southeast.