[1] Tetanurans are defined as all theropods more closely related to modern birds than to Ceratosaurus and contain the majority of predatory dinosaur diversity.

[2] The group was named by Jacques Gauthier in 1986 and originally had two main subgroups: Carnosauria and Coelurosauria, the clade containing birds and related dinosaurs such as compsognathids, tyrannosaurids, ornithomimosaurs, and maniraptorans.

[2] It is however agreed that Megalosauroids, Allosauroids and Coelurosaurians are all members of the Orionides, a subset within Tetanurae that contains dinosaurs more derived than animals such as Chuandongcoelurus and Kayentavenator.

Tetanuran evolution was characterized by parallel diversification of multiple lineages, repeatedly attaining large body size and similar locomotor morphology.

[8] Shared tetanuran features include a ribcage indicating a sophisticated air-sac-ventilated lung system similar to that in modern birds.

[10] At least in South America, carcharodontosaurid allosaurs may have persisted until the end of the Mesozoic Era, and died out at the same time as the non-avian coelurosaurs.

In this type, the skull is about three times longer than tall, with a blunter snout and frequent elaborations such as horns or spikes along the lacrimals, nasals, and frontals.

[2] Most tetanurans possess specialized wrist bones, the absence or reduction of the fourth digit of the hand, a strap-like scapula, stiffened tails, and a laminar astragalar ascending process.

[2] For a century after the description of Megalosaurus, most large carnivorous dinosaurs were serially arrayed into the family Megalosauridae within the order Theropoda.

[2] The size-based arrangement persisted until Gauthier, who redefined Carnosauria and Coelurosauria based on new cladistic analyses but retained the terms.

[16] Initial cladistics studies supported the arrangement of primitive megalosaurs as serial outgroups to a clade of allosaurids, followed by the Coelurosauria.

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.

[17] In 2015, Hendrickx, Hartman and Mateus clarified this definition, specifying it as the least inclusive clade including Allosaurus fragilis, Megalosaurus bucklandii, and Passer domesticus.

In 1999, Paul Sereno named another group, Neotetanurae, for the clade containing Allosauroidea and Coelurosauria, and excluding other tetanurans such as megalosauroids,[20] but this definition was published slightly later.

[10] †Cryolophosaurus †Sinosaurus †Chuandongocoelurus †Monolophosaurus †Piatnitzkysauridae †Spinosauridae †Megalosauridae Coelurosauria †Metriacanthosauridae †Allosauridae †Neovenatoridae †Carcharodontosauridae In 2019, Rauhut and Pol described Asfaltovenator vialidadi, a basal allosauroid displaying a mosaic of primitive and derived features seen within Tetanurae.

[22] Chuandongocoelurus Coelurosauria Monolophosaurus Spinosauridae Megalosauridae Xuanhanosaurus Piatnitzkysauridae Asfaltovenator Metriacanthosauridae Allosaurus Carcharodontosauria The biogeographical history of non-avian Tetanurae spans over 110 million years and all continents.