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One species: Coelophysis bauri. Several other species have been named in the genus, but all have now been found to be the same as C. bauri or moved to other genera.

Coelophysis, a dinosaur of the late Triassic of southwestern North America
Coelophysis, a dinosaur of the late Triassic of southwestern North America

Lived: Triassic to early Jurassic 216 -196 Ma

Location: Fossils have been found in the southwestern U.S., and maybe South Africa, and Zimbabwe.

Coelophysis was first found in the Chinle Formation in New Mexico by collector David Bauer in 1881, Coelophysis was originally described in 1887 by Edward Drinker Cope, for whom Bauer worked. Cope initially assigned it to the genus Coelurus, a dinosaur named by Othniel C Marsh in 1879.

Cope reassigned the species to the new genus Coelophysis in 1889.

In 1947, Edwin Colbert found a huge cache of at least 1,000 Coelophysis fossils at Ghost Ranch, Abiquiú, Rio Arriba County, north-central New Mexico. Several other species of early dinosaurs have also been found at the site.

The ranch was the home of painter Georgia O’Keefe, and is currently open as a retreat and education center. Fossil collecting is not allowed by visitors to the property.

Coelophysis have been found in the Chinle Formation in both New Mexico and Arizona. It is one of the earliest known dinosaurs and probably the best-known of the early dinosaurs because of the number of individuals found.

Only two other dinosaur species have been found from the same time period in the area.

200 million years ago southwestern North America was near the equator. The area of the Chinle Formation was a floodplain, with definite wet and dry seasons.

This is the same time as the animals and plants of Arizona’s Petrified Forest.

Coelophysis was about 9 feet (3 meters) long. They were carnivores, having a varied diet of insects, reptiles, and similar small prey.

Some suggestions of cannibalism have been made, but it appears those are unfounded. The small “babies” found in the region of the stomach were actually lizards, not Coelophysis.

It’s possible that the animals at Ghost Ranch were caught at a waterhole or other sink during a drought, and got caught in a flash flood. This would account for the huge number found at one site.

While this and other finds suggest the animals at least came together at water sources, there is no direct evidence of their hunting in packs. Footprints have been found, however, that have been attributed to Coelophysis or a close relative. They have been found in Connecticut and Rhodesia.

There also is no evidence direct evidence that Coelophysis had feathers. No skin impressions or evidence of other feather-related structures have been found.

Coelophysis would probably have cared for their young, probably for about a year. They laid eggs, and it has been suggested that a clutch would be about two dozen.

Coelophysis was the second dinosaur in space. A skull was taken about the Space Shuttle to the Mir space station in 1998.