A bizarre, humped Carcharodontosauria (Theropoda) from the Lower Cretaceous of Spain

Abstract

Carcharodontosaurs were the largest predatory dinosaurs, and their early evolutionary history seems to be more intricate than was previously thought. Until recently, carcharodontosaurs were restricted to a group of large theropods inhabiting the Late Cretaceous Gondwanan land masses1,2, but in the last few years Laurasian evidence3,4,5 has been causing a reevaluation of their initial diversification6. Here we describe an almost complete and exquisitely preserved skeleton of a medium-sized (roughly six metres long) theropod from the Lower Cretaceous series (Barremian stage) Konservat-Lagerstätte of Las Hoyas7 in Cuenca, Spain. Cladistic analysis supports the idea that the new taxon Concavenator corcovatus is a primitive member of Carcharodontosauria6, exhibiting two unusual features: elongation of the neurapophyses of two presacral vertebrae forming a pointed, hump-like structure and a series of small bumps on the ulna. We think that these bumps are homologous to quill knobs present on some modern birds; the knobs are related to the insertion area of follicular ligaments that anchor the roots of the flight feathers (remiges) to the arm. We propose that Concavenator has integumentary follicular structures inserted on the ulna, as in modern birds. Because scales do not have follicles, we consider the structures anchored to the Concavenator arms to be non-scale skin appendages homologous to the feathers of modern birds. If this is true, then the phylogenetic bracket for the presence of non-scale skin structures homologous to feathers in theropod dinosaurs would be extended to the Neotetanurae, enlarging the scope for explaining the origin of feathers in theropods.

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Figure 1: Holotype of Concavenator corcovatus.
Figure 2: Time-calibrated reduced consensus of the phylogeny of Neotetanurae theropods.
Figure 3: Details of the holotype of Concavenator corcovatus.
Figure 4: Forearm of Concavenator corcovatus.

References

  1. 1

    Currie, P. J. & Carpenter, K. A new specimen of Acrocanthosaurus atokensis (Theropoda, Dinosauria) from the Lower Cretaceous Antlers Formation (Lower Cretaceous, Aptian) of Oklahoma, USA. Geodiversitas 22, 207–246 (2000)

    Google Scholar 

  2. 2

    Novas, F. E., de Valais, S., Vickers-Rich, P. & Rich, T. A large Cretaceous theropod from Patagonia, Argentina, and the evolution of carcharodontosaurids. Naturwissenschaften 92, 226–230 (2005)

    ADS  CAS  Article  Google Scholar 

  3. 3

    Brusatte, S. L. & Sereno, P. C. Phylogeny of Allosauroidea (Dinosauria: Theropoda): comparative analysis and resolution. J. Syst. Paleontol. 6, 155–182 (2008)

    Article  Google Scholar 

  4. 4

    Brusatte, S. L., Benson, R. B. J. & Hutt, S. The osteology of Neovenator salerii (Dinosauria: Theropoda) from the Wealden Group (Barremian) of the Isle of Wight. Monogr. Palaeontogr. Soc. 162, 1–75 (2008)

    Google Scholar 

  5. 5

    Brusatte, S. L. et al. The first definitive carcharodontosaurid (Dinosauria: Theropoda) from Asia and the delayed ascent of tyrannosaurids. Naturwissenschaften 96, 1051–1058 (2009)

    ADS  CAS  Article  Google Scholar 

  6. 6

    Benson, R. B. J., Carrano, M. T. & Brusatte, S. L. A new clade of archaic large-bodied predatory dinosaurs (Theropoda: Allosauroidea) that survived to the latest Mesozoic. Naturwissenschaften 97, 71–78 (2010)

    ADS  CAS  Article  Google Scholar 

  7. 7

    Sanz, J. L., Fregenal-Martínez, M. A., Meléndez, N. & Ortega, F. in Paleobiology II (eds Briggs, D. E. G. & Crowther, P. R.) 356–359 (Blackwell Science, 2001)

    Google Scholar 

  8. 8

    Holtz, T. R., Jr, Molnar, R. E. & Currie, P. J. in The Dinosauria 2nd edn (eds Weishampel, D. B., Dodson, P. & Osmólska, H.) 71–110 (Univ. of California Press, 2004)

    Google Scholar 

  9. 9

    Carrano, M. T. & Sampson, S. D. The phylogeny of Ceratosauria (Dinosauria: Theropoda). J. Syst. Paleontol. 6, 183–236 (2008)

    Article  Google Scholar 

  10. 10

    Sereno, P. C. & Brusatte, S. L. Basal abelisaurid and carcharodontosaurid theropods from the Lower Cretaceous Elrhaz Formation of Niger. Acta Palaeontol. Pol. 53, 15–46 (2008)

    Article  Google Scholar 

  11. 11

    Turner, A. H., Makovicky, P. J. & Norell, M. A. Feather quill knobs in the dinosaur Velociraptor . Science 317, 1721 (2007)

    ADS  CAS  Article  Google Scholar 

  12. 12

    Holtz, T. R., Jr in The Dinosauria 2nd edn (eds Weishampel, D. B., Dodson, P. & Osmólska, H.) 111–136 (University of California Press, 2004)

    Google Scholar 

  13. 13

    Madsen, J. H. Allosaurus fragilis: a revised osteology. Utah Geol. Mineral. Surv. Bull. 109, 1–163 (1976)

    Google Scholar 

  14. 14

    Coria, R. A. & Salgado, L. A new giant carnivorous dinosaur from the Cretaceous of Patagonia. Nature 377, 224–226 (1995)

    ADS  CAS  Article  Google Scholar 

  15. 15

    Coria, R. A. & Currie, P. J. A new carcharodontosaurid (Dinosauria, Theropoda) from the Upper Cretaceous of Argentina. Geodiversitas 28, 71–118 (2006)

    Google Scholar 

  16. 16

    Chuong, C.-M., Chodankar, R., Widelitz, R. B. & Jiang, T.-X. Evo-Devo of feathers and scales: building complex epithelial appendages. Curr. Opin. Genet. Dev. 10, 449–456 (2000)

    CAS  Article  Google Scholar 

  17. 17

    Chuong, C. -M. et al. Adaptation to the sky: defining the feather with integument fossils from Mesozoic China and experimental evidences from molecular laboratories. J. Exp. Zool. B 298, 42–56 (2003)

    Article  Google Scholar 

  18. 18

    Sawyer, R. H. & Knapp, L. W. Avian skin development and the evolutionary origin of feathers. J. Exp. Zool. B 298, 57–72 (2003)

    Article  Google Scholar 

  19. 19

    Taquet, P. Géologie et Paléontologie du Gisement de Gadoufaoua (Aptien du Niger) Cahiers de Paléontologie, CNRS, 1976)

    Google Scholar 

  20. 20

    Norman, D. B. On the anatomy of Iguanodon atherfieldensis (Ornithischia: Ornithopoda). Bull. Inst. R. Sci. Nat. Belg. Sci. Terre 56, 281–372 (1986)

    Google Scholar 

  21. 21

    Paul, G. S. in Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs (ed. Carpenter, K.) 69–77 (Indiana University Press, 2007)

    Google Scholar 

  22. 22

    Brown, B. A new trachodont dinosaur, Hypacrosaurus, from the Edmonton Cretaceous of Alberta. Bull. Am. Mus. Nat. Hist 32, 395–406 (1913)

    Google Scholar 

  23. 23

    Stromer, E. Wirbeltier-Reste der Baharije-Stufe (unterstes Cenoman). 3. Das Original des Theropoden Spinosaurus aegyptiacus nov. gen. Abh. K. Bayer. Akad. Wiss. Mathematisch-physikalische Klasse Abhandlung 28, 1–32 (1915)

    Google Scholar 

  24. 24

    Sereno, P. C. et al. A long-snouted predatory dinosaur from Africa and the evolution of spinosauroids. Science 282, 1298–1302 (1998)

    ADS  CAS  Article  Google Scholar 

  25. 25

    Stovall, J. W. & Langston, W., Jr Acrocanthosaurus atokensis, a new genus and species of Lower Cretaceous Theropoda from Oklahoma. Am. Midl. Nat. 43, 696–728 (1950)

    Article  Google Scholar 

  26. 26

    Olshevsky, G. A revision of the parainfraclass Archosauria Cope, 1869, excluding the advanced Crocodylia. Mesozoic Meanderings 2, 1–196 (1991)

    Google Scholar 

  27. 27

    Bailey, J. B. Neural spine elongation in dinosaurs: sailbacks or buffalo-backs? J. Paleontol. 71, 1124–1146 (1997)

    Article  Google Scholar 

  28. 28

    Zheng, X.-T., You, H., Xing, X. & Dong, Z. An Early Cretaceous heterodontosaurid dinosaur with filamentous integumentary structures. Nature 458, 333–336 (2009)

    ADS  CAS  Article  Google Scholar 

  29. 29

    Mayr, G., Peters, D. S., Plodowski, G. & Vogel, O. Bristle-like integumentary structures at the tail of the horned dinosaur Psittacosaurus . Naturwissenschaften 89, 361–365 (2002)

    ADS  CAS  Article  Google Scholar 

  30. 30

    Alibardi, L. & Toni, M. Cytochemical and molecular characteristics of the process of cornification during feather morphogenesis. Prog. Histochem. Cytochem. 43, 1–69 (2008)

    CAS  Article  Google Scholar 

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Acknowledgements

We thank S. Prieto for information about the location of the specimen; C. Díaz-Romeral, R. de la Fuente, M. García Oliva and N. Santamaría for participating in the field; P. García, M. Llandres, P. Moyano and J. Saiz for specimen preparation; L. Chiappe (Natural History Museum of LA County) for comments on the manuscript; E. Feeman and Plan de Promoción de la Investigación en la Universidad Nacional de Educación a Distancia for manuscript revision; R. Martín for the flesh reconstruction of Concavenator in Fig. 2; and S. Torralba for photography. We acknowledge the Museo de las Ciencias de Castilla-La Mancha for support and funding. Part of this research was financed by project CGL2005-05614 of the Spanish Ministerio de Ciencia e Innovación.

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All authors shared all the phases and topics of the work, both in research and in writing the manuscript. F.O. and F.E. were mainly involved in the description and phylogenetical analysis, whereas J.L.S. was mainly involved in the study of the integumentary evidence. All authors discussed the results and implications and commented on the manuscript at all stages.

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Correspondence to Francisco Ortega.

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The authors declare no competing financial interests.

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Supplementary Information

This file contains Supplementary Information comprising Scores for Concavenator corcovatus, Phylogenetic analysis, Selected measurements for appendicular elements of the holotype specimen, additional references, Supplementary Figures 1-5 with legends and Supplementary Pictures 1-5 with legends. Supplementary Information section 1 was corrected on 05 May 2011. (PDF 16262 kb)

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Ortega, F., Escaso, F. & Sanz, J. A bizarre, humped Carcharodontosauria (Theropoda) from the Lower Cretaceous of Spain. Nature 467, 203–206 (2010). https://doi.org/10.1038/nature09181

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