Range: Angola, Central African Republic, Equatorial Guinea, Gabon, Republic of Congo, the Democratic Republic of Congo

The Western Lowland Gorilla is the nominate species of the genus Gorilla (Savage, 1847; St. Hilaire, 1852). It is the most numerous and widespread sub-species, being found in seven countries in Central Africa. With a population of approximately 100,000 animals, the critically endangered western lowland gorillas are found in the Democratic Republic of Congo, Cameroon, the Central African Republic, and Equatorial Guinea, Gabon, the Republic of Congo and Angola (Cabinda).

Its distribution is bounded by the Atlantic Ocean to the west, the forest boundary just north of the mouth of the Congo River to the south, the Congo and Oubangui Rivers to the east, and the Sanaga River to the north (with the exception of the small relict population in Ebo Forest, Cameroon, whose taxonomic affiliation is still not absolutely clear, but appears to be to G. g. gorilla even though they are north of the Sanaga, Morgan, et al, 2003).

Males silverback have a coloring that extends onto the thighs, also have redder hair on their heads. Western lowland gorillas can be distinguished from other gorilla subspecies by their slightly smaller size, their brown-grey coats and auburn chests. They also have wider skulls with more pronounced brow ridges and smaller ears and the subspecies is believed to be the smallest of all gorilla species.