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Tyrannosaurs Fossil range: Late Cretaceous
Tyrannosaurus rex skull at Palais de la Découverte in Paris.
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Superorder: Dinosauria Order: Saurischia Suborder: Theropoda Superfamily: Tyrannosauroidea Family: Tyrannosauridae Osborn, 1906
Genera
See text.

Tyrannosaurs, tyrant lizards or members of the Tyrannosauridae are a carnivorous dinosaur family whose name is derived from the Greek words tyrannos, meaning 'tyrant' and sauros, meaning 'lizard'.

Tyrannosaurids were originally classified as 'carnosaurs', along with most of the rest of the large theropods. Recent phylogenetic studies, however, have determined that tyrannosaurids are coelurosaurs, a group which also includes the ornithomimids and the maniraptorans. Thus, they are more closely related to dromaeosaurids than to other large predatory dinosaur groups such as the allosaurids. Discoveries of basal, coelurid-like tyrannosauroids have helped solidify this link. ^[1] These discoveries also give evidence that tyrannosauroids may have been feathered.

Tyrannosaurs are characterized by broad, massive skulls, short, powerful necks, and small forelimbs. It was once thought that the tyrannosaurs had only two fingers on each hand, but paleontologists have since discovered that T. rex had three (two primary fingers and one small vestigial finger), raising the probability of the fact that the other tyrannosaurs had them. Notable specimens include "Jane", the world's most complete juvenile T. rex.

• Weight: up to 6.4 tonnes (up to 7 US tons)
• Length: up to 12 metres (up to 40 ft)
• Location: Western Europe, North America, Central and East Asia (area dependent on species)
• Period: Late Cretaceous

The Tyrannosaurids contain several genera and species, of which Tyrannosaurus rex is undoubtedly the most well-known.

• Superfamily Tyrannosauroidea
  • Family Tyrannosauridae
    • Subfamily Albertosaurinae
      • Appalachiosaurus
      • Bagaraatan
      • Tribe Albertosaurini
        • Albertosaurus
        • Gorgosaurus
    • Subfamily Tyrannosaurinae
      • Alioramus
      • Daspletosaurus
      • Tribe Tyrannosaurini
        • Nanotyrannus
        • Tarbosaurus
        • Tyrannosaurus
    • Uncertain placement (incertae sedis)
      • Aublysodon
      • Deinodon

Cladogram after Carr (2005) and Mortimer (2006, online)[1].

Tyrannosauridae
|-?Aublysodon
|-?Deinodon
|--Albertosaurinae
|  |--+--Appalachiosaurus
|  |  `-?+--Bagaraatan
|  |     `-?Xinjiangovenator
|  `--Albertosaurini
|     |--Gorgosaurus
|     `--Albertosaurus
`--Tyrannosaurinae
   |--Daspletosaurus
   `--+-?Alioramus
      |--Tarbosaurus
      |-?Tyrannosaurus? zhuchengensis
      `--Tyrannosaurus