Named By: R. K. Hunt & J. H. Quinn - 2018.
Classification: Chordata, Reptilia, Dinosauria, Saurischia, Ornithomimosauria.
Species: A. fridayi (type).
Size: Unknown due to lack of remains.
Known locations: USA, Arkansas.
Time period: Albian to Aptian of the Cretaceous.
Fossil representation: Partial foot consisting of three metatarsals, four phalanges, and three claws.
discovered in 1973, Arkansaurus was due to be
formally named in
1977, tragically however the papers author Dr. James H. Quinn
was killed in a fall while searching for fossils. Because the paper
was not formally published, the name Arkansaurus
was technically not
valid. The name Arkansaurus however was not
unknown and even got
printed in popular science. Arkansaurus was even
named the state
dinosaur of Arkansas in 2017, and in 2018 a paper formally
describing the genus was published.
As a dinosaur, Arkansaurus was an ornithomimosaur. At the time of writing Arkansaurus is known only from a single partially preserved foot. The claws of the foot have strong curves, something that makes Arkansaurus stand out from other ornithomimosaurs that usually have flat claws. Many relative genera of ornithomimosaurs have been confirmed to have been feathered. By association it is likely that Arkansaurus would have had a feather covering, but the extent and placement is unknown.
- A new ornithomimosaur from the Lower Cretaceous Trinity Group of Arkansas. Journal of Vertebrate Paleontology 38(1):e1421209:1-12. - R. K. Hunt & J. H. Quinn - 2018.