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. 
Tyrannosaurs are characterized by broad, massive skulls, short, powerful necks, and reduced 'arms' with only two digits. 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 14 metres (up to 46 ft)
- Location: Western Europe, North America, Central Asia, and East Asia (area dependent on species)
- Period: Late Cretaceous
- Superfamily Tyrannosauroidea (primitive tyrannosaurs)
Tyrannosauridae |-?Aublysodon |-?Deinodon |--Albertosaurinae | |--+--Appalachiosaurus | | `-?+--Bagaraatan | | `-?Xinjiangovenator | `--Albertosaurini | |--Gorgosaurus | `--Albertosaurus `--Tyrannosaurinae |--Daspletosaurus `--+-?Alioramus |--Tarbosaurus |-?Tyrannosaurus? zhuchengensis `--Tyrannosaurus
- Xu, X., Norell, M. A., Kuang, X., Wang, X., Zhao, Q., and Jia, C. (2004). "Basal tyrannosauroids from China and evidence for protofeathers in tyrannosauroids." Nature, 431: 680-684.