Eastern gorilla
The eastern gorilla ("Gorilla beringei") is a critically endangered species of the genus "Gorilla" and the largest living primate. At present, the species is subdivided into two subspecies. Grauer's gorilla, formerly known as the eastern lowland gorilla ("G. b. graueri") is more populous, at about 3,800 individuals. The mountain gorilla ("G. b. beringei") has only about 1000 individuals. The International Union for the Conservation of Nature mentioned illegal hunting in its assessment of threats to the species.
Cross River gorilla
According to Sarmiento and Oate's study published by the American Museum of Natural History, the Cross River gorilla has been described as having smaller dentitions, smaller palates, smaller cranial vaults, and shorter skulls than other western gorillas. The Royal Belgian Institute of Natural Sciences depicted the Cross River gorilla as the largest living primate with a barrel-chest, relatively even hair, a bare black face and chest, small ears, bare shaped brows that are joined, and nostril margins that are raised. They are clearly not the largest gorillas and the distinctiveness of their external characters still needs to be verified. 
Other Stats include: