Arunachal Pradesh is a state in Northeastern India. It borders the states of Assam and Nagaland to the south. It shares international borders with Bhutan in the west, Myanmar in the east, and a disputed border with China in the north at the McMahon Line. Arunachal Pradesh is the largest of the Seven Sister States of Northeast India by area. Arunachal Pradesh shares a 1,129 km border with China's Tibet Autonomous Region.
The major animal species are Tiger, Leopard, snow leopard, Asian elephant, Sambhar deer, Chital deer, Barking deer, Sloth bear, Mithuna, Gaur, Dhole, Giant squirrel, Marbled cat, Leopard cat. A new subspecies of hoolock gibbon has been described from the state which has been named as the Mishmi Hills hoolock gibbon, Three new giant flying squirrels were also described from the state during the last one and half-decade. These were, Mechuka giant flying squirrel, Mishmi Hills giant flying squirrel, and Mebo giant flying squirrel.