Oligoryzomys is a genus of rodents in the tribe Oryzomyini of family Cricetidae. Many species are known as pygmy rice rats or colilargos. The genus is found from Mexico to Tierra del Fuego and include

Oligoryzomys fulvescens, also known as the fulvous colilargo, fulvous pygmy rice rat, or northern pygmy rice rat, is a species of rodent in the genus Oligoryzomys of family Cricetidae. It is found fro