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.[1] Later concluding the distinctiveness of the material justified a separate genus, Rauhut in 2003 named and described it as the type speciesAviatyrannis jurassica.[2] The species name was by Rauhut given the intended meaning of "tyrant's grandmother from the Jurassic".[2] The generic name is derived from Latinavia, "grandmother", and tyrannus, "tyrant", on the presumption tyrannis would be its genitive.[2] The specific name means "Jurassic".[2]
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.[2] These had in 1998 been described by Jens Zinke.[3] Rauhut also hypothesised that a number of specimens referred to Stokesosaurus might actually belong to Aviatyrannis.[2]
Descriptionedit
Estimated size of Aviatyrannis (here depicted as a tyrannosauroid).
Aviatyrannis was a rather small theropod. The holotype specimen IPFUB Gui Th 1, for example, is an ilium only ninety millimeters long. In 2016, Gregory S. Paul estimated its length at 1 m (3.3 ft) and its body mass at 4 kg (8.8 lb); he also suggested that the holotype possibly belongs to a juvenile.[4] The ilium is elongated and low with the typical tyrannosauroid vertical ridge on the outer blade surface above the hip joint.[2] The teeth of the praemaxilla have a D-shaped cross-section. The maxillary and dentary teeth are elongated, only recurving near the top, with perpendicular denticles on both edges. Their bases are circular in cross-section; the top of the tooth crown is more flattened.[3]
Classificationedit
Aviatyrannis was in 2003 by Rauhut placed in the Tyrannosauroidea, in a basal position.[2] If this placement is correct, Aviatyrannis is one of the oldest tyrannosauroids ever found, the oldest being Proceratosaurus (or, possibly, Iliosuchus).[2] However, a 2023 paper by Hattori et al. noted that the Aviatyrannis ilium is strikingly similar to that of the newly described deinocheiridTyrannomimus. The authors argue that, though more detailed study is needed, Aviatyrannis could be the earliest known ornithomimosaur. The results of their phylogenetic analyses are displayed in the cladogram below:[5]
^Rauhut, O.W.M., 2000, "The dinosaur fauna from the Guimarota mine", pp 75-82 In: Martin and Krebs (eds.). Guimarota - A Jurassic Ecosystem Verlag Dr. Friedrich Pfeil, München
^ abcdefghiOliver W. M. Rauhut. (2003). "A tyrannosauroid dinosaur from the Upper Jurassic of Portugal". Palaeontology. 46 (5): 903–910. doi:10.1111/1475-4983.00325.
^ abZinke, J., 1998, "Small theropod teeth from the Upper Jurassic coal mine of Guimarota (Portugal)", Paläontologische Zeitschrift72(1/2): 179-189
^Paul, Gregory S. (2016). The Princeton Field Guide to Dinosaurs. Princeton University Press. p. 106. ISBN978-1-78684-190-2. OCLC 985402380.
^Hattori, Soki; Shibata, Masateru; Kawabe, Soichiro; Imai, Takuya; Nishi, Hiroshi; Azuma, Yoichi (2023-09-07). "New theropod dinosaur from the Lower Cretaceous of Japan provides critical implications for the early evolution of ornithomimosaurs". Scientific Reports. 13 (1): 13842. doi:10.1038/s41598-023-40804-3. ISSN 2045-2322. PMC10484975.
May 10, 2024
aviatyrannis, genus, coelurosaurian, theropod, dinosaur, possibly, tyrannosauroid, from, oxfordian, tithonian, stages, late, jurassic, found, portugal, temporal, range, late, jurassic, preꞒ, diagram, fossils, assigned, scientific, classification, domain, eukar. Aviatyrannis is a genus of coelurosaurian theropod dinosaur possibly a tyrannosauroid from the Oxfordian Tithonian stages of the Late Jurassic found in Portugal AviatyrannisTemporal range Late Jurassic 160 145 Ma PreꞒ Ꞓ O S D C P T J K Pg N Diagram of fossils assigned to Aviatyrannis Scientific classification Domain Eukaryota Kingdom Animalia Phylum Chordata Clade Dinosauria Clade Saurischia Clade Theropoda Clade Tyrannoraptora Superfamily Tyrannosauroidea Clade Pantyrannosauria Genus AviatyrannisRauhut 2003 Species A jurassica Binomial name Aviatyrannis jurassicaRauhut 2003 Contents 1 Discovery and naming 2 Description 3 Classification 4 See also 5 ReferencesDiscovery and naming editIn 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 1 Later concluding the distinctiveness of the material justified a separate genus Rauhut in 2003 named and described it as the type species Aviatyrannis jurassica 2 The species name was by Rauhut given the intended meaning of tyrant s grandmother from the Jurassic 2 The generic name is derived from Latin avia grandmother and tyrannus tyrant on the presumption tyrannis would be its genitive 2 The specific name means Jurassic 2 The holotype IPFUB Gui Th 1 was found in a layer of the Alcobaca 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 2 These had in 1998 been described by Jens Zinke 3 Rauhut also hypothesised that a number of specimens referred to Stokesosaurus might actually belong to Aviatyrannis 2 Description edit nbsp Estimated size of Aviatyrannis here depicted as a tyrannosauroid Aviatyrannis was a rather small theropod The holotype specimen IPFUB Gui Th 1 for example is an ilium only ninety millimeters long In 2016 Gregory S Paul estimated its length at 1 m 3 3 ft and its body mass at 4 kg 8 8 lb he also suggested that the holotype possibly belongs to a juvenile 4 The ilium is elongated and low with the typical tyrannosauroid vertical ridge on the outer blade surface above the hip joint 2 The teeth of the praemaxilla have a D shaped cross section The maxillary and dentary teeth are elongated only recurving near the top with perpendicular denticles on both edges Their bases are circular in cross section the top of the tooth crown is more flattened 3 Classification editAviatyrannis was in 2003 by Rauhut placed in the Tyrannosauroidea in a basal position 2 If this placement is correct Aviatyrannis is one of the oldest tyrannosauroids ever found the oldest being Proceratosaurus or possibly Iliosuchus 2 However a 2023 paper by Hattori et al noted that the Aviatyrannis ilium is strikingly similar to that of the newly described deinocheirid Tyrannomimus The authors argue that though more detailed study is needed Aviatyrannis could be the earliest known ornithomimosaur The results of their phylogenetic analyses are displayed in the cladogram below 5 Ornithomimosauria LH 02 01 Shenzhousaurus Pelecanimimus Beishanlong Nqwebasaurus Deinocheiridae Harpymimus Aviatyrannis Tyrannomimus Paraxenisaurus Deinocheirus Garudimimus Ornithomimidae Archaeornithomimus asiaticus Bissekty ornithomimid Rativates Sinornithomimus Qiupalong Struthiomimus Ornithomimus edmontonicus Gallimimus AnserimimusSee also editTimeline of tyrannosaur researchReferences edit Rauhut O W M 2000 The dinosaur fauna from the Guimarota mine pp 75 82 In Martin and Krebs eds Guimarota A Jurassic Ecosystem Verlag Dr Friedrich Pfeil Munchen a b c d e f g h i Oliver W M Rauhut 2003 A tyrannosauroid dinosaur from the Upper Jurassic of Portugal Palaeontology 46 5 903 910 doi 10 1111 1475 4983 00325 a b Zinke J 1998 Small theropod teeth from the Upper Jurassic coal mine of Guimarota Portugal Palaontologische Zeitschrift 72 1 2 179 189 Paul Gregory S 2016 The Princeton Field Guide to Dinosaurs Princeton University Press p 106 ISBN 978 1 78684 190 2 OCLC 985402380 Hattori Soki Shibata Masateru Kawabe Soichiro Imai Takuya Nishi Hiroshi Azuma Yoichi 2023 09 07 New theropod dinosaur from the Lower Cretaceous of Japan provides critical implications for the early evolution of ornithomimosaurs Scientific Reports 13 1 13842 doi 10 1038 s41598 023 40804 3 ISSN 2045 2322 PMC 10484975 Retrieved from https en wikipedia org w index php title Aviatyrannis amp oldid 1218691481, wikipedia, wiki, book, books, library,
