Page "Pteranodon" Paragraph 15

Specimens assigned to Pteranodon have been found in both the Smoky Hill Chalk deposits of the Niobrara Formation, and the slightly younger Sharon Springs deposits of the Pierre Shale Formation.

When Pteranodon was alive, this area was covered by a large inland sea, known as the Western Interior Seaway.

Famous for fossils collected since 1870, these formations extend from as far south as Kansas in the United States to Manitoba in Canada.

However, Pteranodon specimens ( or any pterosaur specimens ) have only been found in the southern half of the formation, in Kansas, Wyoming, and South Dakota.

Despite the fact that numerous fossils have been found in the contemporary parts of the formation in Canada, no pterosaur specimens have ever been found there.

This strongly suggests that the natural geographic range of Pteranodon covered only the southern part of the Niobrara, and that its habitat did not extend farther north than South Dakota.