Revueltosaurus

Revueltosaurus ("Revuelto lizard") is a genus of prehistoric crurotarsan from Late Triassic New Mexico and Arizona. According to William Parker, who discovered the partial skeleton, "we have pretty much erased the record of Triassic ornithischian dinosaurs from North America, Europe and worldwide, except for South America." His co-author Randall Irmis said, "because the teeth look like those we know from herbivorous ornithischians, people assigned them to the dinosaurs. We think we've shown that you can't rely on the dentition to determine what is an early dinosaur, which casts doubt on all the ornithischians from the Triassic of North America".

Classification
It was originally described as an ornithischian dinosaur based on several discoveries of teeth, but was reclassified when a partial skeleton was discovered in 2004. Since all purported Triassic ornithischians are known only from teeth and jaw fragments (with the exceptions of Eocursor and Pisanosaurus), the discovery has challenged their validity.