[2] Nota bene: A trinomial authority in parentheses indicates that the subspecies was originally described in a genus other than Trioceros.

[3] The four-horned chameleon is found only in some highland areas associated with the Cameroon line across Cameroon and eastern Nigeria; its range includes the Western High Plateau, the Bamboutos massif, Mount Manengouba, Oku Massif, the Bakossi Mountains including Mount Kupe, and the Obudu Plateau in Nigeria.

The species is primarily associated with relatively intact montane forest with limited human activity, where it has a relatively restricted elevational range of 1,150–2,400 m (3,770–7,870 ft).

[1] Because of its small and fragmented range coupled with numerous threats to its population, the four-horned chameleon is ranked Vulnerable by the International Union for Conservation of Nature.

There are concerns that logging and agricultural expansion may contribute to deforestation and potentially threaten the status of the species by degrading its habitat; in addition, despite its status as a protected Class A species in Cameroon, its intensive exploitation by the pet trade has caused significant population declines in some cases.