A species of monkey unknown to science has been discovered in Arunachal Pradesh, according to the New York-based Wildlife Conservation Society.

Named after Arunachal Pradesh, where it was found, the Arunachal macaque -- a relatively large, brown primate with a comparatively short tail -- is described in a forthcoming issue of the International Journal of Primatology.

The last species of macaque discovered in the wild, the Indonesian Pagai, was described in 1903.

"This new species comes from a biologically rich area that is perhaps India's last unknown frontier," said WCS conservation scientist M D Madhusudan, who was part of the discovery team that included the Nature Conservation Foundation, and its associates.

The Arunachal macaque (Macaca munzala) is the latest addition to the macaque family, a group with some 20 different species occurring mainly in Asia across a variety of different habitats.

It is also one of the highest dwelling primates in the world -- between 1600 and 3500 metres above sea level.

Although it is new to science, the animal is well known to the residents of Tawang and West Kameng districts.