Voalavo

Voalavo is a small rodent resembling a mouse with gray fur. Species of the genus are among the smallest known nesomyines, close in size only to Monticolomys koopmani. In terms of external morphology, Voalavo is barely different from Eliurus; fur coloration patterns, general morphology of the feet, and number of mammae (six) are all the same in both genera. However, all species of Eliurus have a pronounced tuft of elongated hairs at the tip of the tail, a feature that is absent in Voalavo, although the latter does have slightly longer hairs near the tip. The tail is longer than the head and body. Relative tail length in northern voalavo (136% of head and body length) is comparable to that of the longest-tailed species of Eliurus, Grandidier's tufted-tailed rat and Petter's tufted-tailed rat, but V. antsahabensis has a somewhat shorter tail. Furthermore, the pads of the feet are larger in Eliurus, and specifically, the thenar pad (located at the middle of the tarsus) is circular and fairly small in Voalavo, but longer and larger in Eliurus. On the chest, Voalavo species have a gland that produces a sweet-swelling musk in breeding males; this gland is absent in Eliurus. …

Both species of Voalavo occur in montane forest. Northern voalavo is restricted to the Northern Highlands, where it is found at 1,250–1,950 m (4,100–6,400 ft) altitude in Marojejy and Anjanaharibe-Sud. The known range of eastern voalavo is restricted to the vicinity of Anjozorobe at 1,250–1,425 m (4,101–4,675 ft) altitude. Although most of the 450 km (280 mi) between the ranges of the two species consists of montane forest—suitable habitat for Voalavo—the area is bisected by the low-lying Mandritsara Window, which may serve as a barrier between the two species. Subfossil remains of Voalavo have been found in the former Mahajanga Province (northwestern Madagascar). Very little is known of the ecology of eastern voalavo, but northern voalavo is thought to be largely terrestrial with some scansorial (tree-climbing) abilities. It is active during the night, bears up to three young per litter, and probably eats fruits and seeds. Various parasites have been recorded on northern voalavo, including mites and Eimeria.