Coelophysis was a small, bidepal predator. It was about 3 metres and two metres high. It had a long, snake-like neck and tail, and a narrow skull. The jaws were filled with small, pointed teeth.
Coelophysis was a carnivore. It may have eaten insects, baby dinosaurs and other small animals.
It is believed Coelophysis hunted in packs, to bring down larger prey. It has been suggested that they are cannibals, as a fossil of an adult Coelophysis had a baby Coelophysis in its stomach.