Pronounced: see - low - FI - sis
Diet: Carnivore (meat-eater)
Name Means: "hollow form"
Length: 10 feet (3 m)
Height: 4 feet (1.3 m)
Weight: 66 pounds (30 kilos)
Time: Late Triassic - 220 mya
Fossil remains for this Dinosaur have been found in
Southwestern United States
Coelophysis is a very well known early dinosaur as scientists have
discovered hundreds of skeletons of this meat-eater. It is the oldest
dinosaur known in North America. It was a swift hunter that seemed to
eat almost anything it could catch - including other Coelophysis! Some
of the skeletons found in New Mexico had the remains of other
Coelophysis in their stomachs, making it a cannibalistic dinosaur.
Coelophysis could get fairly large for an early dinosaur, with adults
ranging in size from 5 to 10 feet. These sizes are generally divided
into two specimen types - robust and graceful- and are thought to
represent gender differentiation. Being a basal (one of the first)
therapod, it had some characteristics that were lost on later members of
the therapod family. It still had four fingers, although the fourth
digit was quite small.
The remains of hundreds of individuals were found at Ghost Ranch in
New Mexico, which provided scientists with an unprecedented opportunity
to study the individual differences within a large herd of the same
Like other early carnivores, Coelophysis had many small, sharp teeth.
As is shown by the vast numbers of individuals at Ghost Ranch, it is
evident that early dinosaurs exhibited social behavior to the extent of
congregating in large herds. The exact purpose of this large gathering
is not known, but some scientists feel that it may have been breeding
Coelophysis is at the base of the family tree of a great many
dinosaurs including all the Dilophosaurs,
Oviraptor , Ornithomimids and the ever-popular "raptor"
family, which includes Velociraptor
Note that the original type material, which may or may not belong to
the same kind of animal as those later found at Ghost Ranch, has been
given its own (disputed) genus: Eucoelophysis ("true Coelophysis").
A Coelophysis skull became the first dinosaur fossil to be taken into
space in January, 1998 when the Space Shuttle "Endeavor" carried a
specimen from the Carnegie Museum to the Mir Space Station.