Meaning "Two Crested Lizard" Dilophosaurus was discovered in 1954 in Arizona's Kayenta Formation. One species is recognized, Dilophosaurus wetherilli, and it is a highly recognizable species. The most characteristic identifiers of Dilophosaurus are in the skull. Two crests run along the roof of the skull from the nares to the temporal fenestrae. The premaxilla and maxilla abutment is also characteristic of Dilophosaurus and many basal theropods in general. The "kink" where the two meet is also found in later Spinosaurids as well as some crocodiles and represents a weakened connection between the two jaw elements. Despite the popular image of a dinosaur with a transparent hood, like that seen in Jurassic Park, there is no evidence that indicates such a hood existed. There is also no evidence for the venomous nature of the silver screen Dilophosaurus; Michael Crichton took complete ownership of the invention of the two ideas. Dilophosaurus was, however, a rather interesting basal theropod, and a fairly hefty one at 23 feet (7 meters) and up to 2,200 pounds (1,000 kilograms).