Date: Late Cretaceous Period (145-65 million years old), excavated in the 1880s.
Description: The Plesiosaur was an aquatic reptile that roamed the Iowan seas during the Cretaceous Period, along with several varieties of fish and sharks. Their four limbs developed into flippers that could propel them through the water. Plesiosaurs could be anywhere from five feet to nearly fifty feet long, depending on the species. Some had strong jaws to feed on shelled marine animals and bony fish, while others were filter feeders who ate plankton. They were wiped out at the end of the Cretaceous Period by some mass extinction event.
These vertebrae, nearly complete, were discovered by D. H. Talbot, a scientist who worked in Stone State Park. Talbot and a team of workmen discovered these pieces while digging a cistern, and nearly a whole skeleton was excavated under the direction of Mr. J. C. C. Hoskins. The skeleton then became the property of the Sioux City Academy of Science and Letters, who gifted these pieces to the Sioux City Public Museum.
Donor: Sioux City Academy of Science and Letters