Eastern gorilla
There are two recognised subspecies of eastern gorilla: the mountain gorilla ("Gorilla beringei beringei") of the volcanic slopes of Rwanda, Uganda and eastern Democratic Republic of Congo; and Grauer's gorilla or eastern lowland gorilla ("Gorilla beringei graueri") in eastern Democratic Republic of Congo.
Aye-aye
It is the world's largest nocturnal primate, and is characterized by its unusual method of finding food: it taps on trees to find grubs, then gnaws holes in the wood using its forward slanting incisors to create a small hole in which it inserts its narrow middle finger to pull the grubs out. This foraging method is called "percussive foraging", and takes up 5–41% of foraging time. The only other animal species known to find food in this way is the striped possum. From an ecological point of view, the aye-aye fills the niche of a woodpecker, as it is capable of penetrating wood to extract the invertebrates within.