The Coelophysidae are a family of primitive carnivorous theropod dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s. Most species were relatively small in size. The family flourished in the Late Triassic

Late Triassic

The Late Triassic is in the geologic timescale the third and final of three epochs of the Triassic period. The corresponding series is known as the Upper Triassic. In the past it was sometimes called the Keuper, after a German lithostratigraphic group that has a roughly corresponding age...

 and Early Jurassic

Early Jurassic

The Early Jurassic epoch is the earliest of three epochs of the Jurassic period...

 periods.

Under cladistic

Cladistics

Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

 analysis, Coelophysidae was first defined by Paul Sereno

Paul Sereno

Paul Callistus Sereno is an American paleontologist from the University of Chicago who discovered several new dinosaur species on several continents. He has conducted excavations at sites as varied as Inner Mongolia, Argentina, Morocco, and Niger...

 in 1998 as the most recent common ancestor of Coelophysis bauri

Coelophysis

Coelophysis , meaning "hollow form" in reference to its hollow bones , is one of the earliest known genera of dinosaur...

and Procompsognathus triassicus

Procompsognathus

Procompsognathus is a genus of small theropod dinosaur that lived during the late Triassic period , about 210 million years ago. Procompsognathus was named by Eberhard Fraas in 1913. He named the type species, P...

, and all of that common ancestor's descendants.

Coelophysidae is part of the clade Coelophysoidea

Coelophysoidea

Coelophysoids were common dinosaurs of the Late Triassic and Early Jurassic periods. They were widespread geographically, probably living on all continents. Coelophysoids were all slender, carnivorous forms with a superficial similarity to the coelurosaurs, with which they were formerly...

. The older term "Podokesauridae", named 14 years prior to Coelophysidae (which would normally grant it priority), is now usually ignored, since its type specimen was destroyed in a fire and can no longer be compared to new finds.

Classification

• Family Coelophysidae
  • ?Pterospondylus
    Pterospondylus
    Pterospondylus is a dubious genus of theropod dinosaur from the Late Triassic. It was a coelophysoid theropod which lived in what is now Germany . The type species, Pterospondylus trielbae, was described by Jaekel in 1913-14 for a single back vertebra...
    
    
  • Subfamily Coelophysinae
    • Camposaurus
      Camposaurus
      Camposaurus is a coelophysoid dinosaur genus from the Late Triassic of North America. With fossils dating back to the early to middle Norian stage, it is the oldest known neotheropod. It is known from partial lower leg bones, holotype UCMP 34498, and other fragmentary material...
      
      
    • Coelophysis
      Coelophysis
      Coelophysis , meaning "hollow form" in reference to its hollow bones , is one of the earliest known genera of dinosaur...
      
      
    • Megapnosaurus
      Megapnosaurus
      Megapnosaurus was a dinosaur of the theropod family Coelophysidae, formerly called Syntarsus , living during the Early Jurassic. It was renamed by American entomologist Dr. Michael Ivie , Polish Australian Dr...
      
      (formerly Syntarsus)
  • ?Subfamily Podokesaurinae
    • Podokesaurus
      Podokesaurus
      Podokesaurus was a small carnivorous dinosaur of the Early Jurassic Period , and as such is one of the earliest known dinosaurs to inhabit the eastern United States . The small, bipedal carnivore was about 90 cm long and 0.3 m tall...
      
      
  • Subfamily Procompsognathinae
    • Procompsognathus
      Procompsognathus
      Procompsognathus is a genus of small theropod dinosaur that lived during the late Triassic period , about 210 million years ago. Procompsognathus was named by Eberhard Fraas in 1913. He named the type species, P...
      
      
  • Subfamily Segisaurinae
    • Segisaurus
      Segisaurus
      Segisaurus is a genus of small coelophysoid theropod dinosaur, that measured approximately 1 metre in length. The only known specimen was discovered in 1933 in early Jurassic strata in Tsegi Canyon, Arizona, for which it was named. Segisaurus is the only dinosaur to have ever been excavated from...
      
      

Phylogeny

The cladogram

Cladogram

A cladogram is a diagram used in cladistics which shows ancestral relations between organisms, to represent the evolutionary tree of life. Although traditionally such cladograms were generated largely on the basis of morphological characters, DNA and RNA sequencing data and computational...

 below was recovered in a study by Matthew T. Carrano, John R. Hutchinson and Scott D. Sampson, 2005.
The cladogram below follows the topology from a 2011 analysis by paleontologists Martin D. Ezcurra and Stephen L. Brusatte.