The narwhal, or narwhale (Monodon monoceros), is a medium-sized toothed whale and possesses a large "tusk" from a protruding canine tooth. It lives year-round in the Arctic waters around Greenland, Canada, and Russia. It is one of two living species of whale in the Monodontidae family, along with the beluga whale. The narwhal males are distinguished by a long, straight, helical tusk, which is an elongated upper left canine. The narwhal was one of many species described by Carolus Linnaeus in his publication Systema Naturae in 1758.Like the beluga, narwhals are medium-sized whales. For both genders, excluding the male's tusk, the total body size can range from 3.95 to 5.5 metres (13.0 to 18.