Dilophosaurus had a large retractable neck frill and the ability to spit venom.
Dilophosaurus possessed two small bony crests on its head but had no retractable frill or venom-delivery mechanism. The iconic frill-and-venom portrayal in Jurassic Park (1993) was a creative invention by filmmaker Steven Spielberg, inspired in part by modern spitting cobras, but entirely absent from the fossil record. Real Dilophosaurus was a 6-metre-long theropod with limited fossil evidence, but no anatomical features supporting venom production or neck displays.