Nectomys apicalis, also known as the western Amazonian nectomys, is a semiaquatic species of rodent in the genus Nectomys of family Cricetidae. It is found east of the Andes in Ecuador, Peru, and Bolivia, east into western Brazil; further to the east, it is replaced by N. rattus. It lives near watercourses in lowland tropical rainforest. Its karyotype has 2n = 38–42, and it probably actually represents several distinct undescribed species.