Pteranodon ("wing" and "toothless"), from the Late Cretaceous geological period of North America in present day Kansas, Alabama, Nebraska, Wyoming, and South Dakota, was one of the largest pterosaur genera and had a maximum wingspan of over 20 ft. Pteranodon is known from more fossil specimens than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved, with complete skulls and articulated skeletons. Pteranodon was a reptile, but not a dinosaur. Shown here is S.W. Williston's reconstruction of Ornithostoma ingens, a synonym of P. longiceps.