Saurophaganax, meaning “lizard-eating monster,” is a genus of allosaurid dinosaur from the Late Jurassic Period and lived in what is now North America. It comes from the Morrison Formation. It was discovered in the panhandle of Oklahoma, with more possible fossil material found in northern New Mexico.
The identification of Saurophaganax has been disputed fro some time. While being described as its own genus, it has also been described as a species of Allosaurus (A. maximus). The most recent review of primitive tetanurans places Saurophaganax as a distinct genus. New material unearthed in New Mexico may clear up its status.
A lot of material that had been previously referred to as Saurophagus maximus is actually referable to Saurophaganax maximus. The new genus is needed because the original type specimen of Saurophagus maximus is not diagnostic, whereas the material described by Dan Chure is.
Saurophaganax was about 36 feet long and was considered large for an allosaurid. It was bigger than both its equals Torvosaurus tanneri and Allosaurus fragilis. Little is known about its behavior.
Saurophaganax is the official state fossil of Oklahoma. A large skeleton of this dinosaur is on display at the Jurassic Hall in the Sam Noble Oklahoma Museum of Natural History.