The northern voalavo (Voalavo gymnocaudus), also known as the naked-tailed voalavo or simply the voalavo, is a rodent in the family Nesomyidae found in the Northern Highlands of Madagascar. Discovered in 1994 and formally described in 1998, it is the type species of the genus Voalavo; its closest relative is the eastern voalavo of the Central Highlands. DNA sequencing suggests that it may be more closely related to Grandidier's tufted-tailed rat than to other species of the closely related genus Eliurus. The northern voalavo is found at 1,250 to 1,950 m (4,100 to 6,400 ft) above sea level in montane wet and dry forests in the Marojejy and Anjanaharibe-Sud massifs. Nocturnal and solitary, it lives mainly on the ground, but it can climb and probably eats plant matter. Despite having a small