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Tyrannosaurinae

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Tyrannosaurinae
Temporal range: Late Cretaceous,
81.9–66 Ma (possible Cenomanian occurrence of Labocania)
Skull of Alioramus.
Skull of Tyrannosaurus.
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: Tyrannosauridae
Subfamily: Tyrannosaurinae
Osborn, 1906
Type genus
Tyrannosaurus
Osborn, 1905
Subgroups[4]

Tyrannosaurinae (or tyrannosaurines) is one of the two extinct subfamilies of Tyrannosauridae, a family of coelurosaurian theropods that consists of at least three tribes and several genera. All fossils of these genera have been found in the Late Cretaceous deposits of western North America and east Asia. Compared to the related subfamily Albertosaurinae, tyrannosaurines overall are more robust and larger though the alioramins were gracile by comparison. This subfamily also includes Lythronax, one of the oldest known tyrannosaurid genera, as well as the youngest and most famous member of the group, Tyrannosaurus rex.

History of discovery

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Deinodon teeth, the earliest known tyrannosaurid remains

The first remains of tyrannosaurids were uncovered during expeditions led by the Geological Survey of Canada, which located numerous scattered teeth. These distinctive dinosaur teeth were given the name Deinodon ("terrible tooth") by Joseph Leidy in 1856. In 1892 Edward Drinker Cope described more tyrannosaur material in the form of isolated vertebrae, and gave this animal the name Manospondylus gigas. This discovery was mostly overlooked for over a century, and caused controversy in the early 2000s when it was discovered that this material actually belonged to, and had name priority over, Tyrannosaurus rex.[5] Later in 1905 Henry Fairfield Osborn described two tyrannosaur specimens that had been collected in Montana and Wyoming during a 1902 expedition of the American Museum of Natural History, led by Barnum Brown. Initially, Osborn considered these to be distinct species. The first, he named Dynamosaurus imperiosus ("emperor power lizard"), and the second, Tyrannosaurus rex ("king tyrant lizard"). A year later, Osborn recognized that these two specimens actually came from the same species. Despite the fact that Dynamosaurus had been found first, the name Tyrannosaurus had appeared one page earlier in his original article describing both specimens. Therefore, according to the International Code of Zoological Nomenclature (ICZN), the name Tyrannosaurus was used.[6]

The second described representative of the tyrannosaurines, Tarbosaurus (originally described as an Asiatic representative of Tyrannosaurus) was in 1955 after a large skull was recovered in a joint Soviet-Mongolian expedition to the Gobi Desert in the Mongolian Ömnögovi Province in 1946. The holotype was named as Tyrannosaurus bataar by Evgeny Maleev as Tyrannosaurus bataar.[7] The genus Tarbosaurus was also described in the same year based on PIN 551–2, a specimen with a skull and skeletal remains discovered by the same expedition in 1948 and 1949 as Tarbosaurus efremovi.[8] It was only in 1965 that Ty. bataar and Ta. efremovi were the same species, the latter being a younger animal, and distinct from Tyrannosaurus recognized by A.K. Rozhdestvensky who recombined the species as Tarbosaurus bataar.[9]

In the 1970s saw the description of two genera. In 1970 saw the publication of Daspletosaurus, with the holotype CMN 8506 consisting of a partial skeleton including the skull, the shoulder, a forelimb, the pelvis, a femur and all of the vertebrae from the neck, torso and hip, as well as the first eleven tail vertebrae. It was discovered in 1921 near Steveville, Alberta, by Charles Mortram Sternberg, who thought it was a new species of Gorgosaurus, but was found to be a new genus by Dale Russell using the aforementioned CMN 8506.[10] The second, Alioramus, described in 1976 by Sergei Kurzanov which the holotype (PIN 3141/1) is a partial skull associated with three metatarsals found by a joint Soviet-Mongolian expedition to the Gobi Desert in the early 1970s found these remains at a locality known as Nogon-Tsav in the Mongolian province of Bayankhongor, Nemegt Formation.[11]

From 1977 to 2009 saw the publications of several genera. In Asia they include Shanshanosaurus (1977),[12] Maleevosaurus (1992),[13] and Raptorex (2009),[14] while in North America saw Nanotyrannus (1988),[15] Dinotyrannus and Stygivenator (1995).[16] These genera, however are controversial as the remains of these animals are immature or juvenile individuals. With the possible exception of Raptorex,[17] it is widely assumed that the Asian specimens are early growth stages of Tarbosaurus,[18][19][20] whereas the North American specimens are those of Tyrannosaurus.[21][22]

Skeletal reconstruction of two tyrannosaurs superimposed over each other, with known bones highlighted in yellow; photographs of various fossils appear below
Skeletal diagrams showing holotype remains of Lythronax (A) and a Teratophoneus specimen (B). N–P show selected bones of the former

Valid genera would not be named until the 2010s, where in 2011 announced the publication of Teratophoneus by Thomas D. Carr and colleagues. The fossils were first found in the Kaiparowits Formation of southern Utah. Later, fossils from the same formation were discovered and identified as the genus. Argon-argon radiometric dating indicates that the Kaiparowits Formation was deposited between 76.1 and 74.0 million years ago, during the Campanian stage of the Late Cretaceous period. This date means that Teratophoneus lived in the middle of the Campanian stage of the Late Cretaceous.[23] In the same year Zhuchengtyrannus was named by David W. E. Hone and colleagues based on the holotype ZCDM V0031, a nearly complete right maxilla and associated left dentary (lower jaw, both with teeth) housed at Zhucheng Dinosaur Museum.[24] In 2014 came Nanuqsaurus, the northern most tyrannosaurid found in Prince Creek Formation of the North Slope of Alaska, United States.[25][26] In the same year also announced Qianzhousaurus known from a partial sub-adult individual consisting of a nearly complete skull with the lower jaws missing all teeth (lost during fossilization), 9 cervical vertebrae, 3 dorsal vertebrae, 18 caudal vertebrae, both scapulocoracoids, partial ilia, and the left hindlimb compromising the femur, tibia, fibula, astragalus with calcaneum, and metatarsals III and IV.[27] Lythronax, the oldest known member of Tyrannosauridae, was described in 2013 by Mark A. Loewen and colleagues from a nearly complete specimen that was uncovered in 2009 in the Wahweap Formation of the Grand Staircase–Escalante National Monument.[28]

Natural history

[edit]

Description

[edit]
Size of A. remotus compared with a human
The specimens "Sue", AMNH 5027, "Stan", and "Jane", to scale with a human.

In comparison to the albertosaurines, tyrannosaurines were more heavily built and larger. The alioramin genera of Qianzhousaurus and Alioramus, however, were the exception, as they were more comparable in built to albertosaurines and have longirostrine snouts.[27] Like albertosaurines, tyrannosaurines also had heterodont dentition, large heads design to catch and kill their prey, and short didactyl arms. Based on the growth stages of Tyrannosaurus (and possibly Tarbosaurus[20]), tyrannosaurines undergone ontogenetic changes from gracile or slender, semi-longirostrine immatures to robust, heavy-headed adults. This implies that these animals occupy different ecological niches as they developed.[22] While there is fossil evidence of earlier tyrannosauroids having feathers,[29][30] the evidence of such structures in tyrannosaurids is controversial as a study in 2017 from Bell and colleagues found no support in feathered integument in tyrannosaurids.[31] The study used skin impressions which are small, found widely dispersed across the post-cranium at different regions of the body with a pattern similar to crocodiles. Further the croc analogy Thomas Carr and colleagues in 2017 by studying the snout of Daspletosaurus suggested they have large scales with sensory sensory neuron pits under the skin.[32] This notion has been challenged from other authors who suggested a more lip-covering of the teeth.[33]

Distribution

[edit]

The temporal range for tyrannosaurines went from almost 80.6 million years ago in the Campanian stage of the Late Cretaceous epoch to 66 million years ago in the Maastrichtian stage. Fossils have been found in different formations in what is now east Asia and western North America. While the Asian alioramins are the basal most group of the tyrannosaurines, the geographic placement of albertosaurines and other eutyrannosaurian tyrannosauroids found in North America suggests greatly the tyrannosaurines are North American in origin.[34]

Systematics

[edit]

Prior to the 2010s, the relationships of the tyrannosaurines was best understood as Tyrannosaurus being a sister taxon to Tarbosaurus. These two genera in turn were the sister taxon to Daspletosaurus, follow by Alioramus. There was an alternative hypothesis from Phil Currie and colleagues (2003) who suggested Daspletosaurus to be more closely related to Tarbosaurus and Alioramus than to Tyrannosaurus based on cranial features.[35] This relationship, however, has not been found in more recent studies.[23][25][28][34][36] In 1988 Gregory Paul considered all tyrannosaurines at the time except Alioramus to be species of Tyrannosaurus.[37] In the second edition of The Princeton Field Guide to Dinosaurs published in 2016, Paul would continue this thought as well as including Bistahieversor, Teratophoneus, Lythronax, and Nanuqsaurus into the genus as well.[38] This multispecies Tyrannosaurus classification is, however, not widely accepted by most paleontologists.[36] In some phylogenetic studies Bistahieversor is nested within Tyrannosaurinae,[25][28] but it is most often recovered as the sister taxon to Tyrannosauridae instead.[34][36]

The cladogram below displays the position of the Tyrannosaurinae within Eutyrannosauria and Tyrannosauridae, based on the results of phylogenetic analyses performed by Voris et al. (2020):[36]

Eutyrannosauria

As of 2023, at least three lineages of tyrannosaurines have been suggested.[36] The basalmost clade is the Alioramini. The second clade to diverge is the Teratophoneini, which comprises the American southwest taxa Dynamoterror, Lythronax, and Teratophoneus. They are sister to a third clade comprising Nanuqsaurus and the clade containing Daspletosaurini, which includes Daspletosaurus and Thanatotheristes, and the Tyrannosaurini, which includes Zhuchengtyrannus, Tarbosaurus, and Tyrannosaurus.[2]

The cladogram below displays the results of the strict consensus phylogenetic analysis performed by Scherer & Voiculescu-Holvad (2023), indicating the distinct lineages of tyrannosaurines.[2]

References

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  1. ^ Zheng, Wenjie; Jin, Xingsheng; Xie, Junfang; Du, Tianming (2024-07-25). "The first deep-snouted tyrannosaur from Upper Cretaceous Ganzhou City of southeastern China". Scientific Reports. 14 (1): 16276. Bibcode:2024NatSR..1416276Z. doi:10.1038/s41598-024-66278-5. ISSN 2045-2322. PMC 11272791. PMID 39054316.
  2. ^ a b c d Scherer, Charlie Roger; Voiculescu-Holvad, Christian (2023-11-28). "Re-analysis of a dataset refutes claims of anagenesis within Tyrannosaurus-line tyrannosaurines (Theropoda, Tyrannosauridae)". Cretaceous Research. 155: 105780. doi:10.1016/j.cretres.2023.105780. ISSN 0195-6671.
  3. ^ Rivera-Sylva, Héctor E.; Longrich, Nicholas R. (2024). "A New Tyrant Dinosaur from the Late Campanian of Mexico Reveals a Tribe of Southern Tyrannosaurs". Fossil Studies. 2 (4): 245–272. doi:10.3390/fossils2040012.
  4. ^ Holtz, Thomas R. Jr. (2012) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2011 Appendix. Archived 2017-08-12 at the Wayback Machine
  5. ^ Breithaupt, B.H.; Southwell, E.H.; Matthews, N.A. (18 October 2005). "In Celebration of 100 years of Tyrannosaurus rex: Manospondylus gigas, Ornithomimus grandis, and Dynamosaurus imperiosus, the Earliest Discoveries of Tyrannosaurus rex in the West". Abstracts with Programs. 2005 Salt Lake City Annual Meeting. Vol. 37. Geological Society of America. p. 406. Archived from the original on 22 October 2019. Retrieved 8 October 2008.
  6. ^ Breithaup, BH; Southwell EH; Matthews NA (2006). "Dynamosaurus imperiosus and the earliest discoveries of Tyrannosaurus rex in Wyoming and the West". New Mexico Museum of Natural History and Science Bulletin. 35: 257–258.
  7. ^ Maleev, Evgeny A. (1955). "Giant carnivorous dinosaurs of Mongolia". Doklady Akademii Nauk SSSR. 104 (4): 634–637.
  8. ^ Maleev, E. A. (1955). "New carnivorous dinosaurs from the Upper Cretaceous of Mongolia" (PDF). Doklady Akademii Nauk SSSR. 104 (5). translated by F. J. Alcock: 779–783.
  9. ^ Rozhdestvensky, Anatoly K. (1965). "Growth changes in Asian dinosaurs and some problems of their taxonomy". Paleontological Journal. 3: 95–109.
  10. ^ Russell, Dale A. (1970). "Tyrannosaurs from the Late Cretaceous of western Canada". National Museum of Natural Sciences Publications in Paleontology. 1: 1–34.
  11. ^ Kurzanov, Sergei M. "A new carnosaur from the Late Cretaceous of Nogon-Tsav, Mongolia". The Joint Soviet-Mongolian Paleontological Expedition Transactions (in Russian). 3: 93–104.
  12. ^ Dong Zhiming (1977). "On the dinosaurian remains from Turpan, Xinjiang". Vertebrata PalAsiatica (in Chinese). 15: 59–66.
  13. ^ Carpenter, Ken. (1992). "Tyrannosaurids (Dinosauria) of Asia and North America". In Mateer, Niall J.; Peiji, Chen (eds.). Aspects of Nonmarine Cretaceous Geology. Beijing: China Ocean Press. pp. 250–268.
  14. ^ Sereno, P.; Tan, L.; Brusatte, S. L.; Kriegstein, H. J.; Zhao, X.; Cloward, K. (2009). "Tyrannosaurid skeletal design first evolved at small body size". Science. 326 (5951): 418–422. Bibcode:2009Sci...326..418S. doi:10.1126/science.1177428. PMID 19762599. S2CID 1953405.
  15. ^ Bakker, R.T.; Williams, M.; Currie, P.J. (1988). "Nanotyrannus, a new genus of pygmy tyrannosaur, from the latest Cretaceous of Montana". Hunteria. 1: 1–30.
  16. ^ Olshevsky, G. (1995). "The origin and evolution of the tyrannosaurids". Kyoryugaku Saizensen [Dino Frontline]. 9–10: 92–119.
  17. ^ Carr, Thomas D. (2022-11-25). "A reappraisal of tyrannosauroid fossils from the Iren Dabasu Formation (Coniacian–Campanian), Inner Mongolia, People's Republic of China". Journal of Vertebrate Paleontology. 42 (5). Bibcode:2022JVPal..42E9817C. doi:10.1080/02724634.2023.2199817. ISSN 0272-4634.
  18. ^ Carr, Thomas D. (1999). "Craniofacial ontogeny in Tyrannosauridae (Dinosauria, Coelurosauria)". Journal of Vertebrate Paleontology. 19 (3): 497–520. Bibcode:1999JVPal..19..497C. doi:10.1080/02724634.1999.10011161. S2CID 83744433.
  19. ^ Currie, Philip J.; Dong Zhiming (2001). "New information on Shanshanosaurus huoyanshanensis, a juvenile tyrannosaurid (Theropoda, Dinosauria) from the Late Cretaceous of China" (PDF). Canadian Journal of Earth Sciences. 38 (12): 1729–1737. Bibcode:2001CaJES..38.1729C. doi:10.1139/cjes-38-12-1729.
  20. ^ a b Fowler, DW; Woodward, HN; Freedman, EA; Larson, PL; Horner, JR (2011). "Reanalysis of "Raptorex kriegsteini": A Juvenile Tyrannosaurid Dinosaur from Mongolia". PLOS ONE. 6 (6): e21376. Bibcode:2011PLoSO...621376F. doi:10.1371/journal.pone.0021376. PMC 3126816. PMID 21738646.
  21. ^ Woodward, Holly N.; Tremaine, Katie; Williams, Scott A.; Zanno, Lindsay E.; Horner, John R.; Myhrvold, Nathan (2020). "Growing up Tyrannosaurus rex: Osteohistology refutes the pygmy "Nanotyrannus" and supports ontogenetic niche partitioning in juvenile Tyrannosaurus". Science Advances. 6 (1): eaax6250. Bibcode:2020SciA....6.6250W. doi:10.1126/sciadv.aax6250. ISSN 2375-2548. PMC 6938697. PMID 31911944.
  22. ^ a b Carr, T.D. (2020). "A high-resolution growth series of Tyrannosaurus rex obtained from multiple lines of evidence". PeerJ. 8: e9192. doi:10.7717/peerj.9192.
  23. ^ a b Carr, T.D.; Williamson, T.E.; Britt, B.B.; Stadtman, K. (2011). "Evidence for high taxonomic and morphologic tyrannosaurid diversity in the Late Cretaceous (Late Campanian) of the American Southwest and a new short-skulled tyrannosaurid from the Kaiparowits formation of Utah". Naturwissenschaften. 98 (3): 241–246. Bibcode:2011NW.....98..241C. doi:10.1007/s00114-011-0762-7. PMID 21253683. S2CID 13261338.
  24. ^ Hone, D. W. E.; Wang, K.; Sullivan, C.; Zhao, X.; Chen, S.; Li, D.; Ji, S.; Ji, Q.; Xu, X. (2011). "A new, large tyrannosaurine theropod from the Upper Cretaceous of China". Cretaceous Research. 32 (4): 495–503. Bibcode:2011CrRes..32..495H. doi:10.1016/j.cretres.2011.03.005.
  25. ^ a b c Fiorillo, A. R.; Tykoski, R. S. (2014). Dodson, Peter (ed.). "A Diminutive New Tyrannosaur from the Top of the World". PLoS ONE. 9 (3): e91287. Bibcode:2014PLoSO...991287F. doi:10.1371/journal.pone.0091287. PMC 3951350. PMID 24621577.
  26. ^ Fiorillo, Anthony R.; Gangloff, Roland A. (2000). "Theropod teeth from the Prince Creek Formation (Cretaceous) of northern Alaska, with speculations on Arctic Dinosaur paleoecology". Journal of Vertebrate Paleontology. 20 (4): 675. doi:10.1671/0272-4634(2000)020[0675:TTFTPC]2.0.CO;2. S2CID 130766946.
  27. ^ a b Lü, J.; Yi, L.; Brusatte, S. L.; Yang, L.; Chen, L. (2014). "A new clade of Asian Late Cretaceous long-snouted tyrannosaurids". Nature Communications. 5 (3788): 3788. Bibcode:2014NatCo...5.3788L. doi:10.1038/ncomms4788. PMID 24807588.
  28. ^ a b c Loewen, M.A.; Irmis, R.B.; Sertich, J.J.W.; Currie, P.J.; Sampson, S.D. (2013). Evans, D.C (ed.). "Tyrant dinosaur evolution tracks the rise and fall of Late Cretaceous oceans". PLoS ONE. 8 (11): e79420. Bibcode:2013PLoSO...879420L. doi:10.1371/journal.pone.0079420. PMC 3819173. PMID 24223179.
  29. ^ Xu Xing, X; Norell, Mark A.; Kuang Xuewen; Wang Xiaolin; Zhao Qi; Jia Chengkai. (2004). "Basal tyrannosauroids from China and evidence for protofeathers in tyrannosauroids" (PDF). Nature. 431 (7009): 680–684. Bibcode:2004Natur.431..680X. doi:10.1038/nature02855. PMID 15470426. S2CID 4381777.
  30. ^ Xu, X.; Wang, K.; Zhang, K.; Ma, Q.; Xing, L.; Sullivan, C.; Hu, D.; Cheng, S.; Wang, S.; et al. (2012). "A gigantic feathered dinosaur from the Lower Cretaceous of China" (PDF). Nature. 484 (7392): 92–95. Bibcode:2012Natur.484...92X. doi:10.1038/nature10906. PMID 22481363. S2CID 29689629. Archived from the original (PDF) on 17 April 2012.
  31. ^ Bell, P. R.; Campione, N. E.; Persons, W. S.; Currie, P. J.; Larson, P. L.; Tanke, D. H.; Bakker, R. T. (2017). "Tyrannosauroid integument reveals conflicting patterns of gigantism and feather evolution". Biology Letters. 13 (6): 20170092. doi:10.1098/rsbl.2017.0092. PMC 5493735. PMID 28592520.
  32. ^ Carr, Thomas D.; Varricchio, David J.; Sedlmayr, Jayc C.; Roberts, Eric M.; Moore, Jason R. (2017-03-30). "A new tyrannosaur with evidence for anagenesis and crocodile-like facial sensory system". Scientific Reports. 7: 44942. Bibcode:2017NatSR...744942C. doi:10.1038/srep44942. ISSN 2045-2322. PMC 5372470. PMID 28358353.
  33. ^ Milinkovitch, Michel; Manukyan, Liana; Debry, Adrien; Di-Po, Nicolas; Martin, Samuel; Singh, Dalijit; Lambert, Dominique; Zwicker, Matthias (January 4, 2013). "Crocodile Head Scales Are Not Developmental Units But Emerge from Physical Cracking". Science. 339 (6115): 78–81. Bibcode:2013Sci...339...78M. doi:10.1126/science.1226265. PMID 23196908. S2CID 6859452.
  34. ^ a b c Delcourt, R.; Grillo, O. N. (2018). "Tyrannosauroids from the Southern Hemisphere: Implications for biogeography, evolution, and taxonomy". Palaeogeography, Palaeoclimatology, Palaeoecology. 511: 379–387. Bibcode:2018PPP...511..379D. doi:10.1016/j.palaeo.2018.09.003. S2CID 133830150.
  35. ^ Currie, Philip J.; Hurum, Jørn H.; Sabath, Karol (2003). "Skull structure and evolution in tyrannosaurid phylogeny" (PDF). Acta Palaeontologica Polonica. 48 (2): 227–234. Archived from the original (PDF) on October 25, 2007.
  36. ^ a b c d e Voris, Jared T.; Therrien, Francois; Zelenitzky, Darla K.; Brown, Caleb M. (2020). "A new tyrannosaurine (Theropoda:Tyrannosauridae) from the Campanian Foremost Formation of Alberta, Canada, provides insight into the evolution and biogeography of tyrannosaurids". Cretaceous Research. 110: 104388. Bibcode:2020CrRes.11004388V. doi:10.1016/j.cretres.2020.104388. S2CID 213838772.
  37. ^ Paul, Gregory S. (1988). Predatory Dinosaurs of the World. New York: Simon & Schuster. pp. 464pp. ISBN 978-0-671-61946-6.
  38. ^ Paul, Gregory S. (2016). The Princeton Field Guide to Dinosaurs. Princeton: Princeton University Press. p. 360. ISBN 9781400883141.