fossil of a flounder-like flatfish on white background

fossil flounder flatfish isolated white background fish dinosaurs fossilized relic ancient animal archaeological archaeology body bone extinct fauna fossile fossilisation fossils fulllength historic history life million nature neogene old palaeontology palaeotheriidae paleogene percomorph petrification petrified pre prehistoric prehistorical prehistory primeval remain science single skeleton species stone times vestige vestiges wild years