Open Paleo

Aviatyrannis

Rauhut, 2003 AY-vi-uh-TIE-ran-iss

From Latin 'avia' (grandmother) and 'tyrannis' (genitive of 'tyrannus', tyrant); meaning 'the tyrant's grandmother'.

161.5–143.1 million years ago Oxfordian–Tithonian, Late Jurassic
Late Jurassic stages

Aviatyrannis is a genus of coelurosaurian theropod dinosaur, either a tyrannosauroid or an ornithomimosaurian, from the Oxfordian-Tithonian stages of the Late Jurassic found in Portugal.

Under dispute

The affinities of Aviatyrannis are contested. It was described as a basal tyrannosauroid (Rauhut, 2003) and is treated as such by most subsequent work, but Hattori and colleagues (2023) argued from the holotype ilium that it is instead an ornithomimosaur, recovering it in supplementary analyses either as the earliest deinocheirid, sister to Tyrannomimus, or outside both ornithomimosaur families near Shenzhousaurus; that result is unstable and was excluded from their primary tree. It is placed conservatively at Tyrannosauroidea following the prevailing view.

Diagnosis

  1. Ilium low and elongate, with a well-developed, vertical, hollow ridge above the acetabulum
  2. Dorsal half of anterior margin of preacetabular blade shallowly concave
  3. Anterodorsally facing concavity set off from the dorsal rim of the preacetabular blade
  4. Narrow, sharply defined, rounded vertical ridge extending over almost the complete height of the ilium above the acetabulum
  5. Pubic peduncle of ilium transversely narrow, more than three times longer anteroposteriorly than wide at its middle

Species

Aviatyrannis jurassica Rauhut, 2003

Type species

Refers to the Jurassic age of the holotype.

Holotype
IPFUB Gui Th 1 , Museu Geológico do Instituto Geológico e Mineiro
Material
Almost complete right ilium
Notes
Originally held at the Lehrstuhl für Paläontologie of the Free University, Berlin, and marked with the acronym IPFUB; the Guimarota material is now in the Museu Geológico, Lisbon.
Horizon
Alcobaça Formation, Oxfordian–Tithonian, Late Jurassic , 161.5–143.1 million years ago
Locality
Guimarota, Leiria, Portugal

References

  1. Rauhut, O. W. M. (2003). A tyrannosauroid dinosaur from the Upper Jurassic of Portugal. Palaeontology 46(5): 903-910. Wiley. doi:10.1111/1475-4983.00325 rauhut2003a
  2. Hattori, S.; Shibata, M.; Kawabe, S.; Imai, T.; Nishi, H.; Azuma, Y. (2023). New theropod dinosaur from the Lower Cretaceous of Japan provides critical implications for the early evolution of ornithomimosaurs. Scientific Reports 13(1). Springer Science and Business Media LLC. doi:10.1038/s41598-023-40804-3

    Phylogenetic re-evaluation arguing the holotypic ilium shares ornithomimosaur features; recovered alternately as earliest deinocheirid or as sister to Shenzhousaurus.

    hattori2023a
  3. Paul, G. S. (2024). The Princeton Field Guide to Dinosaurs (3rd ed.). Princeton University Press.

    Source of the body length and mass estimates.

    paul2024a
  4. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.

    Source of the hip height estimate.

    jones2026c
  5. Mateus, O.; Milàn, J. (2009). A diverse Upper Jurassic dinosaur ichnofauna from central-west Portugal. Lethaia 43: 245-257. doi:10.1111/j.1502-3931.2009.00190.x

    Records the holotype as held by the Museu Geológico, formerly IPFUB Gui Th 1.

    mateus2009b