STL Science Center

STL Science Center

26 September 2014

Stokes and Cleveland

Illustrated by Conty
William Lee Stokes and James Madsen are famous for the remains they recovered from the Cleveland-Lloyd Quarry in Utah. Thousands of bones were recovered by the pair including a number of Allosaurus remains. In 1974 Madsen cataloged those remains not then described, numbered, and stored. One of these sets of remains he noted as being entirely new to science. This dinosaur he described and named Stokesosaurus clevelandi in honor of his partner and the small Utah town of Cleveland where the quarry is located. The name has stood for 40 years now (there was a brief window from 1976-1980 when Peter Galton considered these remains to be potentially synonymous with British remains of the genus Iliosuchus) despite the holotype consisting of an isolated juvenile ilium, a paratype consisting of an ilium one and a half times larger, and a referred premaxilla. The premaxilla has somewhat recently been referred to Tanycolagreus, another small theropod considered to be more advanced. Opinions are somewhat divided but some consider Tanycolagreus a junior synonym of Stokesosaurus. In 1991 and 1998 new materials, ischia and caudal vertebrae and a partial braincase respectively, were attributed to Stokesosaurus. Studies of the remains continue to show up now and again and in 2012 novel characters were described from Stokesosaurus that allow it to continue to retain its position as a valid taxon. Things have changed drastically in where Stokesosaurus belongs on the family trees however. Described as a small generic tyrannosaur, Stokesosaurus is presently considered to be, more specifically, a proceratosaurid tyrannosaur. Tomorrow we will attempt to explain what that means exactly through the use of imagery and artistic interpretation.

No comments:

Post a Comment