ichthyosaur swimming in the ocean, extinct marine reptile from early triassic to late cretaceous, 3d paleoart rendering

animal aquatic carnivore carnivorous creature cretaceous dangerous dinosaur early era eurhinosaurus evolution extinct fish giant huge ichthyosaur ichthyosaurus jurassic large late life lizard marine monster ocean paleoart paleontologist paleontology predator prehistoric primeval rendering reptile sea shastasaurus shonisaurus stenopterygius swimming triassic underwater vertebrate water