Neotheropoda (meaning "new theropods") is a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

that includes

coelophysoid Coelophysoidea 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 ...

s and more advanced theropod

dinosaurs Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

, and is the only group of theropods that survived the Triassic–Jurassic extinction event. All neotheropods became extinct by the end of the Early Jurassic ( Pliensbachian) period except for Averostra.

Classification

Neotheropoda was named by

Robert T. Bakker Robert Thomas Bakker (born March 24, 1945) is an American paleontologist who helped reshape modern theories about dinosaurs, particularly by adding support to the theory that some dinosaurs were endothermic (warm-blooded). Along with his mentor J ...

in 1986 as a group including the relatively derived theropod subgroups Ceratosauria and Tetanurae, and excluding

coelophysoids Coelophysoidea 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 ...

. However, most later researchers have used it to denote a broader group. Neotheropoda was first defined as a

by Paul Sereno in 1998 as '' Coelophysis'' plus modern birds, which includes almost all theropods except the most primitive species.Sereno, 1998. A rationale for phylogenetic definitions, with application to the higher-level taxonomy of Dinosauria. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 210, 41-83. Dilophosauridae was formerly considered a small clade within Neotheropoda, but was later considered to be

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

. The following family tree illustrates a synthesis of the relationships of the early theropod groups compiled by Hendrickx ''et al.'' in 2015.Hendrickx, C., Hartman, S.A., & Mateus, O. (2015)
An Overview of Non- Avian Theropod Discoveries and Classification
''PalArch’s Journal of Vertebrate Palaeontology'', 12(1): 1-73. This second cladogram is based on the redescription of ''Dilophosaurus'' by Marsh and Rowe (2020). This third cladogram is based on the larger analysis in the description of ''

Pendraig milnerae ''Pendraig'' (meaning "chief dragon" in Middle Welsh) is a genus of coelophysoid theropod dinosaur from South Wales. It contains one species, ''Pendraig milnerae'', named after Angela Milner. The specimen was discovered in the Pant-y-Ffynnon quarr ...

'' by Spiekman ''et al.'' 2021:

References

{{Taxonbar, from=Q145206 * Late Triassic first appearances Taxa named by Robert T. Bakker