| Aviatyrannis Fossil range: Late Jurassic | |
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| Scientific classification
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Aviatyrannis | |
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Aviatyrannis is a genus of tyrannosaurid dinosaur from the Kimmeridgian stage of the Late Jurassic found in Portugal. It was described by Oliver Rauhut in 2003. The name means "Jurassic grandmother tyrant". Aviatyrannis is one of the oldest tyrannosaurs ever found, the oldest being Guanlong (or, possibly, Iliosuchus).
Aviatyrannis may have been a contemporary of another ancient tyrannosaur, the American Stokesosaurus. Aviatyrannis was even originally assigned to Stokesosaurus, and the fragmentary nature of the referred material fails to fully resolve the possibility that the two taxa are synonyms.
Description[]
Like other early tyrannosaurs, Aviatyrannis was rather small. The holotype (IPFUB Gui Th 1), for example, is an ilium only 90 millimeters long. The type species, Aviatyrannis jurassica, was described by Rauhut in 2003.
Discovery and naming[]
In 2000 Oliver Walter Mischa Rauhut reported the find of tyrannosauroid material in the lignite coal mine of Guimarota near Leiria, which he referred to Stokesosaurus. Later concluding the distinctiveness of the material justified a separate genus, Rauhut in 2003 named and described it as the type species Aviatyrannis jurassica. The species name was by Rauhut given the intended meaning of "tyrant's grandmother from the Jurassic". The generic name is derived from Latin avia, "grandmother", and tyrannus, "tyrant", on the presumption tyrannis would be its genitive. The specific name means "Jurassic".
The holotype, IPFUB Gui Th 1, was found in a layer of the Alcobaça Formation dating from the early Kimmeridgian, about 155 million years old. It consists of a right ilium. Rauhut in 2003 referred two other bones to Aviatyrannis: IPFUB Gui Th 2, a partial right ilium, and IPFUB Gui Th 3, a right ischium. The referred elements represent slightly larger individuals. Additionally sixteen isolated teeth were referred: IPFUB GUI D 89-91: three teeth of the premaxilla, and IPFUB GUI D 174-186: thirteen teeth of the maxilla and dentary. These had in 1998 been described by Jens Zinke. Rauhut also hypothesised that a number of specimens referred to Stokesosaurus might actually belong to Aviatyrannis.
Classification[]
Aviatyrannis was in 2003 by Rauhut placed in the Tyrannosauroidea, in a basal position. Aviatyrannis is one of the oldest tyrannosauroids ever found, the oldest being Proceratosaurus (or, possibly, Iliosuchus).
Twenty years later in 2023 a publication of Tyrannomimus Placed it in the Ornithomimidae.
References[]
- Oliver W. M. Rauhut. (2003). "A tyrannosauroid dinosaur from the Upper Jurassic of Portugal". Palaeontology 46: 903–910. doi:.
External links[]
- Aviatyrannis at DinoData
