The term 'long-armed ape' refers to three species of primates: the ORANGUTAN, the GIBBON, and the ORANG. The ORANGUTAN is a large, reddish-brown primate native to Southeast Asia, and is the largest arboreal mammal in the world. The GIBBON is a small, agile ape found in tropical and subtropical rainforests of Southeast Asia, and is known for its loud calls and long arms. The ORANG is a species of great ape native to Indonesia and Malaysia, and is the most arboreal of the great apes. All three species are characterized by their long arms, which they use to swing from tree to tree.