This species can grow from about 30 to 40 cm in length and weigh 120 to 150 grams.
The Usambara three-horned chameleon is found in Afrotemperate rain forest patches in multiple mountain ranges. It lives in isolated populations, usually away from the forest edge, within a range of about 1,400 km2. It is endemic to East Usambara, Uluguru, Nguu and Nguru Mountains, and Udzungwa Mountains.