The variety of habitats found in the Simandou Range include humid Guinean savanna, Western Guinean lowland forest, montane and gallery forests, and the rare and endangered West African montane grassland habitat. The Pic de Fon forest at the southern end of the range is a relatively intact area of approximately 25,600 ha that contains many typical flora and fauna of the Guinean montane forests ecosystem, including endangered species such as the Nimba otter shrew (Micropotamogale lamottei), the West African chimpanzee (Pan troglodytes verus), the Diana monkey (Cercopithecus diana diana) and the Sierra Leone prinia (Schistolais leontica), a bird of the West African highlands known from only three other sites in the world. Frog Hylarana fonensis is known from nowhere else.