Berylmys

Berylmys is a genus of large, arboreal rats found in Southeast Asia. These rodents are characterized by their glossy, reddish-brown fur, large ears, and long, bushy tails. The genus currently contains three recognized species: Berylmys bowersi, Berylmys mackenziei, and Berylmys berdmorei.

Berylmys bowersi, commonly known as Bowers's rat, is the largest species and is found in the mountains of Borneo and Sumatra. It inhabits primary forests and is typically found at elevations between 1,000 and 2,000 meters. Berylmys mackenziei, or Mackenzie's rat, has a more restricted distribution, found only in parts of Thailand and Myanmar. Berylmys berdmorei, known as Berdmore's rat, is widespread across mainland Southeast Asia, from Myanmar to Vietnam and southern China.

These rats are primarily nocturnal and are thought to feed on a variety of fruits, seeds, and insects. They are skilled climbers, and their large size and arboreal lifestyle are distinguishing features within the Muridae family. Little is known about the specific reproductive biology or social behavior of Berylmys species due to their elusive nature and inhabitation of dense, remote forests. Conservation statuses vary among the species, with some facing threats from habitat loss and degradation.