No fossil record of chimpanzees or gorillas?

Just saw a brief mention of same on Wiki, is this true? How can such a thing be?

FWIW I think there have been numerous fossil apes found.

See Fossil apes

This is the only cite I found on Wiki referencing this claim -An article on Bigfoot.

You are talking two specific genera: Pan for the chimps and Gorilla. Both dwell in tropical forests, by and large, which is not conducive to fossilization. The John Hawks website that astro linked to has any number of fossil ape genera listed. (Note that many of these were “plains apes” and at least one lived in swamps – both better suited to fossilization than forest terrain.)

Some chimpanzee fossils have been found very recently. It seems one wandered out of the rainforest and lost some teeth, half a million or so years ago.