No African fossil apes have been found from between 10 - 7 million years ago (the period during which African apes and hominids diverged).
(Hominini (humans and chimps) split off from Gorillini some 10 mya. Genus
Homo (humans) split off genus
Pan (chimps) some 7 mya.)
From about the 7 - 6 mya period, several possible ancestors of chimpanzees have been found in East and Central Africa, such as:
Sahelanthropus tchadensis (7 mya: Central Africa) Teeth and skull more hominin-like than ape-like.
Possibly latest known common ancestor of chimps and humans, or oldest known human ancestor after the human/chimp split, or related to both but ancestral to neither, or is a female proto-gorilla. Thickened brow ridges similar to later fossil hominids such as
Homo erectus, but different from
Australopithecus and extant humans. Possibly bipedal based on anterior position of foramen magnum. Brain case 340 – 360 cc.
Ardipithecus kadabba (5.8 – 5.2 mya: Northern Africa) Size of modern chimps. Shares certain traits with
Gorilla and
Pan, indicating proper placement on chimp branch rather than human. Shares “canine cutting complex” with modern chimpanzees, not shared by
Homo. Evidence of woodland, grassland and swamp habitat.
Ardipithecus ramidus (4.4 mya: Northern Africa) Size of modern chimps. Shares certain traits with Gorilla and
Pan, indicating proper placement on chimp branch rather than human, but has dentition similar to
Australopithecus ("Lucy"). Lacks “canine cutting complex” which modern chimps have, a primitive trait lost during hominin evolution. Possible biped based on toe structure. Not considered hominin ancestor by scientists. Evidence of woodland, grassland and swamp habitat.
Even after the 7 mya time stamp, chimpanzee and gorilla fossils are rare, but they do exist.
Chimp fossils were first discovered in Kenya in 2005:
These fossils, from the Kapthurin Formation, Kenya, show that representatives of Pan were present in the East African Rift Valley during the Middle Pleistocene [~800 - 125 thousand years ago], where they were contemporary with an extinct species of Homo. Habitats suitable for both hominins and chimpanzees were clearly present there during this period, and the Rift Valley did not present an impenetrable barrier to chimpanzee occupation.
As to gorillas, the fossil record is similarly scarce, but some
fossil 'gorilla' teeth from about 10 million years ago were found in Ethiopia in 2007 and given a new species name,
Chororapithecus abyssinicus.
the teeth, eight molars and a canine, are collectively indistinguishable from modern gorilla subspecies in size, proportion and scan-revealed internal structure.
Does that satisfy? Or may I be of further assistance?
