The Arizonasaurus....Can you guess where it was found? That's right. Arizona , Texas for the most part. It wasn't actually considered an actual dinosaur although it looks like it would fit under that category. It was part of a group of prehistoric Crocodiles. These "Croc's" where as large as 10 feet in length and are thought to have been vicious predators of the middle ages of the Triassic period. The Arizonasaurus had a strange sail on its back just like the Dimetrodon, even though these two dinosaurs are not closely related. The only reason they had that in common because the area they are from is the same climate. The hot desert Ecosystem. Actually this would explain the huge sail too because its' purpose for being there would be to take in a lot of heat and draw out heat. This would be a great way of the dinosaur to control its activity being fast when it needs to be, but relaxed when resting. This was very necessary to be able to catch some of the faster herbivores.