coelophysis

Coelophysis is a genus of small theropod dinosaurs that lived during the Late Triassic period, about 210 to 200 million years ago. It is one of the earliest well-known theropods, and its fossils have been found mainly in the southwestern United States, with some material reported from Africa (notably Zimbabwe). The genus was named by Edward Drinker Cope in 1887, and the type species is Coelophysis bauri.

Coelophysis was a slender, bipedal predator with a light, elongated skeleton. Adults were typically around 2 to 3 meters long and weighed roughly 20 to 40 kilograms. It had a long neck, a narrow skull with sharp, serrated teeth, and long hind limbs suited to running. The hands had three slender fingers, and the tail was long to aid balance.

Fossils from the Ghost Ranch area near Abiquiu, New Mexico constitute one of the best-known Triassic assemblages of Coelophysis and have provided substantial information about the genus. The Ghost Ranch material includes individuals at various growth stages, which has led to discussion about population structure and mortality events. African specimens once attributed to Coelophysis, including some from Zimbabwe, have been debated and are often considered either a closely related species or a separate genus.

Coelophysis was likely carnivorous, feeding on small vertebrates and possibly insects or carrion. Its proportionally long legs and probable agility suggest it was a fast runner, useful for pursuing prey or evading larger predators.

As an early theropod, Coelophysis contributes to understanding the early radiation of predatory dinosaurs and the ecosystems of the Triassic period.