Cretaceous fauna. Artwork depicting animals that existed in the Cretaceous period (144 to 65 million years ago). Depicted on the left are the dinosaurs Saltasaurus (upper left), Protoceratops with young and Brachiosaurus (large, lower left), also with young. The pterosaur Nyctosaurus is at top. Depicted at upper right is Styracosaurus (multi-horned,) and Tarbosaurus (orange, top right). Below these (left to right) are: Maiasaura, Stegoceras and Euoplocephalus. The bird at bottom right is Ichthyornis, opposite the mammal Deltathridium.