Eastern lowland gorilla

The eastern lowland gorilla or Grauer's gorilla ("Gorilla beringei graueri") is a subspecies of eastern gorilla. It is native to the mountainous forests of eastern Democratic Republic of the Congo. 
It is the largest of the four gorilla subspecies. It has jet black coats like the mountain gorilla ("Gorilla beringei beringei"), although the hair is shorter on the head and body. The male's coat, like that of other gorillas, greys as the animal matures, resulting in the designation "silverback".