- Tetanurae
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Tetanurans
Temporal range: Early Jurassic–Recent, 189–0 Ma
Possible Late Triassic recordScientific classification Kingdom: Animalia Phylum: Chordata Class: Reptilia Superorder: Dinosauria Order: Saurischia Suborder: Theropoda Node: Neotheropoda Branch: Tetanurae
Gauthier, 1986Subgroups Tetanurae, or "stiff tails", is a clade that includes most theropod dinosaurs, as well as birds. Tetanurans (or tetanurines) first appear during the early or middle Jurassic Period.
Contents
Definition
Tetanurae meaning "stiff tails", was named by Jacques Gauthier on cladistic grounds in 1986 for a large group of theropod dinosaurs. Gauthier's paper was the first serious application of the science of cladistics to vertebrate paleontology.
Tetanurae are defined as all theropods more closely related to modern birds than to Ceratosaurus (e.g. Padian et al., 1999). Gauthier considered it to consist of Carnosauria and Coelurosauria, although many of what he considered carnosaurs have been regarded as coelurosaurs or basal tetanurans by subsequent workers (but see Rauhut, 2003). Paul Sereno (1999) named Neotetanurae for the node joining Carnosauria (his Allosauroidea) and Coelurosauria, excluding other tetanurans such as megalosauroids. Padian et al. (1999) gave a synonymous definition for Gregory Paul's (1988) Avetheropoda, but this definition was published slightly later.
Range
It is not entirely clear where the origins of Tetanurae are. Cryolophosaurus has been claimed as the first true member of the group (although this identification has been disputed and Cryolophosaurus now appears to be closer to the dilophosaurids). Even if Cryolophosaurus was a tetanuran, this leaves no true tetanuran fossils from the Triassic, when the group should have originated based on the presence of coelophysoids (if the old definition of Ceratosauria is used). This gives heavier validity to the more recent view of tetanurans and ceratosaurs sharing a common ancestor and forming a clade of advanced theropods together.
Large, predatory spinosaurids and allosaurids flourished during the Late Jurassic and Early Cretaceous, especially in Gondwana, but seem to have died out before the end of the Cretaceous, possibly due to competition from abelisaurid ceratosaurs and tyrannosaurid coelurosaurs. The diverse coelurosaurs persisted until the end of the Mesozoic Era, when all except for crown clade avians died out. Modern birds are the only living representatives of the clade Tetanurae.
Classification
- Tetanurae
- †Cruxicheiros
- †Gasosaurus
- †Kaijiangosaurus
- †Kayentavenator
- †Shidaisaurus
- †Szechuanosaurus
- †Xuanhanosaurus
- †Megalosauroidea [=Spinosauroidea]
- Avetheropoda
- †Allosauroidea (see also Carnosauria)
- Coelurosauria (incl. Aves)
Popular tetanurans
Many popular dinosaurs are tetanurans, including Allosaurus, Oviraptor, Spinosaurus, Tyrannosaurus, Velociraptor, as well as the ancient bird Archaeopteryx and all species of modern birds. The first Mesozoic dinosaur to be named was Megalosaurus bucklandii, a basal tetanuran.
References
- Gauthier, J. A. (1986). "Saurischian monophyly and the origin of birds". In Padian, K.. The Origin of Birds and the Evolution of Flight. Memoirs of the California Academy of Sciences. 8. California Academy of Sciences. pp. 1–55. ISBN 780940228146
- Padian, K.; Hutchinson, R. M.; Holtz, T.R. Jr. (1999). "Phylogenetic definitions and nomenclature of the major taxonomic categories of the carnivorous Dinosauria (Theropoda)". Journal of Vertebrate Paleontology 19 (1): 69–80. doi:10.1080/02724634.1999.10011123.
- Paul, G. S. (1988). Predatory Dinosaurs of the World. New York: Simon and Schuster. ISBN 0671619462.
- Rauhut, O. W. M. (2003). The interrelationships and evolution of basal theropod dinosaurs. Special Papers in Palaeontology. 69. Wiley. ISBN 090170279X.
- Sereno, P. C. (1999). "The evolution of dinosaurs". Science 284 (5423): 2137–2147. doi:10.1126/science.284.5423.2137. PMID 10381873.
Categories:- Theropods
- Tetanurae
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