Open Paleo

Tyrannosauroidea

Osborn, 1906 Type genus Tyrannosaurus

Its genera lived 168.2–66.0 million years ago Middle Jurassic–Late Cretaceous

Tyrannosauroidea is a superfamily of coelurosaurian theropod dinosaurs that unites the family Tyrannosauridae with a range of smaller, more basal relatives such as the proceratosaurids. The group arose on the northern supercontinent Laurasia in the Jurassic and persisted until the end of the Cretaceous, when tyrannosauroids became the dominant large predators of the Northern Hemisphere, culminating in the giant Tyrannosaurus; their fossils are known from what are now North America, Europe, and Asia. All members were bipedal carnivores distinguished by a suite of skull and pelvic features, including a tall premaxilla that blunted the front of the snout, fused and often roughly textured nasal bones, and small, D-shaped premaxillary teeth. Early forms were small animals with long, three-fingered forelimbs, whereas the later giants reached enormous size yet had proportionately tiny, two-fingered arms; the derived forms also developed a pinched third metatarsal, the arctometatarsus, tied to running efficiency. Primitive filamentous feathers are preserved in several species, and many tyrannosauroids bore bony crests of varied shape on the skull that likely served for display.

Diagnosis

  1. Tall premaxilla forming a blunt snout tip
  2. Fused, rugose-textured nasal bones
  3. Small, D-shaped (asymmetric) premaxillary teeth
  4. Braincase with a deep otic recess (columellar canal) bearing an internal fenestra vestibuli
  5. Elongate cochlear duct, indicating heightened sensitivity to low-frequency sound
  6. Tubular brain endocast with only a slight midbrain flexure
  7. Pronounced midbrain peak on the endocast, anterior to the posterior middle cerebral vein
  8. Indistinct flocculus that barely crosses the plane of the anterior semicircular canal

Clades within Tyrannosauroidea

Genera placed directly in Tyrannosauroidea

  • Alectrosaurus Gilmore, 1933 Coniacian–Maastrichtian (89.8–66.0 Ma)China
  • Aviatyrannis Rauhut, 2003 Oxfordian–Tithonian (161.5–143.1 Ma)Portugalunder dispute
  • Calamosaurus Lydekker, 1891 Barremian (125.8–121.4 Ma)United Kingdom
  • Chingkankousaurus Nomen dubium Young, 1958 Campanian (83.6–72.2 Ma)Chinaunder dispute
  • Dilong Xu et al., 2004 Barremian (125.8–121.4 Ma)China
  • Diplotomodon Nomen dubium Leidy, 1868 Campanian–Maastrichtian (83.6–66.0 Ma)United States
  • Eotyrannus Hutt et al., 2001 Barremian (125.8–121.4 Ma)United Kingdom
  • Jinbeisaurus Wu et al., 2020 Cenomanian–Campanian (100.5–72.2 Ma)China
  • Juratyrant Brusatte & Benson, 2013 Tithonian (149.2–143.1 Ma)United Kingdom
  • Khankhuuluu Voris et al., 2025 Turonian–Santonian (93.9–83.6 Ma)Mongolia
  • Labocania Molnar, 1974 Cenomanian–Campanian (100.5–72.2 Ma)Mexicoincertae sedisunder dispute
  • Moros Zanno et al., 2019 Cenomanian (100.5–93.9 Ma)United States
  • Raptorex Disputed Sereno et al., 2009 Maastrichtian (72.2–66.0 Ma)incertae sedis
  • Stokesosaurus Madsen, 1974 Kimmeridgian–Tithonian (154.8–143.1 Ma)United States
  • Suskityrannus Nesbitt et al., 2019 Turonian (93.9–89.8 Ma)United States
  • Timurlengia Brusatte et al., 2016 Turonian (93.9–89.8 Ma)Uzbekistan
  • Xiongguanlong Li et al., 2010 Aptian (121.4–113.2 Ma)China

References

  1. Osborn, H. F. (1906). Tyrannosaurus, Upper Cretaceous carnivorous dinosaur (second communication). Bulletin of the American Museum of Natural History 22: 281-296.

    Proposed the family Tyrannosauridae, from which the superfamily name takes its authorship by coordination.

    osborn1906a
  2. Holtz, T. R. (2004). Tyrannosauroidea. The Dinosauria, Second Edition (Weishampel, D. B.; Dodson, P.; Osmólska, H., eds.) 111-136. University of California Press, Berkeley.

    Defined Tyrannosauroidea as Tyrannosaurus rex and all taxa closer to it than to Ornithomimus velox, Deinonychus antirrhopus or Allosaurus fragilis, and diagnosed it.

    holtz2004b
  3. Brusatte, S. L.; Averianov, A.; Sues, H. D.; Muir, A.; Butler, I. B. (2016). New tyrannosaur from the mid-Cretaceous of Uzbekistan clarifies evolution of giant body sizes and advanced senses in tyrant dinosaurs. Proceedings of the National Academy of Sciences 113(13): 3447-3452. Proceedings of the National Academy of Sciences. doi:10.1073/pnas.1600140113

    Described the braincase and endocast of Timurlengia, showing the shallow endocast and long cochlear duct that earlier studies identify as tyrannosauroid synapomorphies.

    brusatte2016a