Orionidans
Temporal range:
Middle JurassicPresent, 175.6–0 Ma
Possible Early Jurassic record
Piatnitzkysaurus floresi2.jpg
Skeleton of Piatnitzkysaurus floresi
Keel-billed toucan woodland.jpg
Keel-billed toucan perched on a branch
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Clade: Tetanurae
Clade: Orionides
Carrano, Benson & Sampson, 2012
Clades

Orionides is a clade of tetanuran theropod dinosaurs from the Middle Jurassic to the Present. The clade includes most theropod dinosaurs, including birds.[1]

Relationships

Although many phylogenetic analyses found basal tetanurans that were outside both Megalosauroidea and Avetheropoda, the core dichotomy was named only in 2012. Carrano, Benson and Sampson (2012) named that clade Orionides, and defined it as the node comprising Megalosauroidea, Avetheropoda, their most recent common ancestor, and all its descendants. In 2015, Hendrickx, Hartman and Mateus clarified this definition, specifying it as the most recent common ancestor of Allosaurus fragilis, Megalosaurus bucklandii, and Passer domesticus, and all its descendants. The cladogram presented below follows a phylogenetic analysis published by Zanno and Makovicky in 2013.[2]

Orionides
Megalosauroidea

Piatnitzkysauridae Piatnitzkysaurus floresi by Paleocolour.jpg

Megalosauria

SpinosauridaeSpinosaurus aegyptiacus.png

MegalosauridaeTorvosaurus tanner DBi.jpg

Avetheropoda

CoelurosauriaMeyers grosses Konversations-Lexikon - ein Nachschlagewerk des allgemeinen Wissens (1908) (Antwerpener Breiftaube).jpg

Allosauroidea

MetriacanthosauridaeYangchuanosaurus NT (flipped).jpg

Allosauria

AllosauridaeAllosaurus Revised.jpg

Carcharodontosauria

NeovenatoridaeGualicho shinyae restoration.jpg

CarcharodontosauridaeConcavenator corcovatus by Daniel Vidal 2012.png

In 2019 saw the description and publication of Asfaltovenator vialidadi, a basal allosauroid that curiously has characteristics displaying primitive and derived features seen in Tetanurae. Their phylogenetic analysis has found Megalosauroidea to be a basal grade of carnosaurs in respect to Allosauroidea.[3]

 Orionides 
 Avetheropoda 

CoelurosauriaMeyers grosses Konversations-Lexikon - ein Nachschlagewerk des allgemeinen Wissens (1908) (Antwerpener Breiftaube).jpg

Carnosauria

SpinosauridaeSpinosaurus aegyptiacus.png

MegalosauridaeTorvosaurus tanner DBi.jpg

Piatnitzkysauridae Piatnitzkysaurus floresi by Paleocolour.jpg

Allosauroidea

Asfaltovenator vialidadi

MetriacanthosauridaeYangchuanosaurus NT (flipped).jpg

Allosauria

AllosauridaeAllosaurus Revised.jpg

Carcharodontosauria

NeovenatoridaeNeovenator.png

CarcharodontosauridaeCarcharodontosaurus.png

Range

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.

Etymology

The clade name "Orionides" was first established by Matthew T. Carrano, Roger B. J. Benson and Scott D. Sampson in 2012. It is derived from Orion, the giant hunter of Greek mythology in references to the large size and carnivorism of basal orionidans. The name also refers to the alternative name for the constellation of Orion, Alektropodion, meaning "rooster foot".[1]

References

  1. ^ a b Carrano, M. T.; Benson, R. B. J.; Sampson, S. D. (2012). "The phylogeny of Tetanurae (Dinosauria: Theropoda)". Journal of Systematic Palaeontology. 10 (2): 211–300. doi:10.1080/14772019.2011.630927.
  2. ^ Zanno, L. E.; Makovicky, P. J. (2013). "Neovenatorid theropods are apex predators in the Late Cretaceous of North America". Nature Communications. 4: 2827. Bibcode:2013NatCo...4.2827Z. doi:10.1038/ncomms3827. PMID 24264527.
  3. ^ Rauhut, Oliver W. M.; Pol, Diego (2019-12-11). "Probable basal allosauroid from the early Middle Jurassic Cañadón Asfalto Formation of Argentina highlights phylogenetic uncertainty in tetanuran theropod dinosaurs". Scientific Reports. 9 (1): 18826. doi:10.1038/s41598-019-53672-7. ISSN 2045-2322. PMC 6906444. PMID 31827108.