Parker's initial fossil finds were crocodilian-like armor, but he didn't realize they were from Revueltosaurus until the next day, when he brought a colleague to the site and she picked up a jaw with teeth. During May and June of 2004, Parker, Irmis and their coauthors excavated one complete Revueltosaurus skeleton from the 6-square meter quarry they dug, plus bones from more than a dozen other individuals. In June of 2005, a second relatively complete skeleton was uncovered from the same site.
Irmis, who first started working in the park with Parker in 2002 as an undergraduate at Northern Arizona University, said that this crocodilian ancestor was only three to four feet long, with a stubbier, less flattened skull and a less sprawling leg posture than today's crocodiles have. Also, the armor did not cover the entire body, but was restricted to two lines down the back. The creature is most similar, he said, to a group of Triassic archosaurs - the group that includes crocodiles, dinosaurs and birds - called the aetosaurs.
Irmis, Parker and Nesbitt are continuing their look at the alleged ornithischians of the Late Triassic to ascertain the quality of the fossil record and what it says about early dinosaur evolution.