, Volume 90, Issue 3, pp 593–609 | Cite as

A new rhynchosaur from south Brazil (Santa Maria Formation) and rhynchosaur diversity patterns across the Middle-Late Triassic boundary

  • Cesar Leandro Schultz
  • Max Cardoso Langer
  • Felipe Chinaglia Montefeltro
Research Paper


The rhynchosaur previously referred to as the “Mariante Rhynchosaur” is here formally described as a new genus and species based on two specimens: a complete skull (without the lower jaw) articulated with the three first cervical vertebrae and a set of right maxilla and dentary. Both specimens were collected at the same site in Rio Grande do Sul, Brazil, from deposits of the Santa Maria Formation considered of Ladinian (Middle Triassic) age. Diagnostic characters include the contact between prefrontal and postfrontal, a pair of deep frontal grooves, and a very deep skull. A new phylogenetic analysis recovered the new taxon as a member of the Stenaulorhynchinae, a relatively diverse clade of Middle Triassic rhynchosaurs, with records in India, east Africa, and the Americas. Evidence suggests that the extinction of that clade took place in the context of a faunal turnover across the Ladinian-Carnian boundary, when it was replaced by the much more abundant Late Triassic hyperodapedontine rhynchosaurs.


Stenaulorhynchinae Ladinian Dinodontosaurus AZ Rio Grande do Sul Phylogeny 


Der früher als “Mariante Rhynchosaur” bezeichnete Rhynchosaurier wird hier, anhand zweier Exemplare (ein unterkieferloser kompletter Schädel mit den drei ersten Halswirbeln sowie ein Satz rechter Oberkiefer und Dentale), formell als neue Gattung und Art beschrieben. Beide Exemplare wurden in der selben Lagerstätte in Rio Grande do Sul, Brasilien, gefunden, in Ablagerungen der Santa Maria Formation aus dem Zeitalter des Ladinium (Mittlere Trias). Diagnostische Merkmale beinhalten den Kontakt zwischen Pre- und Postfrontale, ein Paar tiefer frontaler Furchen, und einen sehr tiefen Schädel. Eine neue phylogenetische Analyse positionierte das neue Taxon als Mitglied der Stenaulorhynchinae, eine relative vielfältige Klade an Rhynchosauriern des Mittleren Trias, mit Funden aus Indien, Ostafrika und den Amerikas. Hinweise deuten darauf, dass das Aussterben der Klade im Zusammenhang eines Faunenaustausches an der Ladinium-Karnium Grenze stattfand, als sie durch die viel häufigeren hyperodapedontinen Rhynchosaurier des Späten Trias ersetzt wurden.


Stenaulorhynchinae Ladinium Dinodontosaurus AZ Rio Grande do Sul Phylogenie 



Max Langer research is supported by FAPESP Grant # 2014/03825–3). The authors thank the Paläontologische Zeitschrift reviewers Mike Benton and Martin Ezcurra for their useful comments. Photographs taken by Luiz Flávio P. Lopes, drawings by Bianca M. Mastrantonio, CLS Grant: CNPq 309995/2013-2.

Supplementary material

12542_2016_307_MOESM1_ESM.docx (35 kb)
Supplementary material 1 (DOCX 41 kb)


  1. Abdala, F., and A.M. Ribeiro. 2010. Distribution and diversity patterns of Triassic cynodonts (Therapsida, Cynodontia) in Gondwana. Palaeogeography, Palaeoclimatology, Palaeoecology 286: 202–217.CrossRefGoogle Scholar
  2. Abdala, F., and A.M. Sá-Teixeira. 2004. A traversodontid cynodont of African affinity in the South American Triassic. Palaeontologia Africana 40: 11–22.Google Scholar
  3. Abdala, F., A.M. Ribeiro, and C.L. Schultz. 2001. A rich cynodont fauna of Santa Cruz do Sul, Santa Maria Formation (Middle-Late Triassic), southern Brazil. Neues Jahrbuch für Geologie und Paläontologie Monatshefte 11: 669–687.Google Scholar
  4. Abdala, F., A.G. Martinelli, M.B. Soares, M. de la Fuente, and A.M. Ribeiro. 2009. South American Middle Triassic continental faunas with amniotes: biostratigraphy and correlation. Palaeontologia Africana 44: 83–87.Google Scholar
  5. Abdala, F., C.A. Marsicano, R.M. Smith, and R. Swart. 2013. Strengthening Western Gondwanan correlations: a Brazilian Dicynodont (Synapsida, Anomodontia) in the Middle Triassic of Namibia. Gondwana Research 23: 1151–1162.CrossRefGoogle Scholar
  6. Andreis, R. R., G.E. Bossi, and D.K. Montardo. 1980. O Grupo Rosário do Sul, Triássico no Rio Grande do Sul. In Anais do XXXI Congresso Brasileiro de Geologia. 2: 659–673. Camboriú, Siciedade Brasileira de Geologia.Google Scholar
  7. Bandyopadhyay, S., T.K. Roy Chowdhury, and D.P. Sengupta. 2002. Taphonomy of some Gondwana vertebrate assemblages of India. Sedimentary Geology 147: 219–245.CrossRefGoogle Scholar
  8. Benton, M.J. 1983a. The Triassic reptile Hyperodapedon from Elgin: functional morphology and relationships. Philosophical Transaction of the Royal Society B 302: 605–717.CrossRefGoogle Scholar
  9. Benton, M.J. 1983b. Dinosaur success in the Triassic: a noncompetitive ecological model. The Quarterly Review of Biology 58: 29–55.CrossRefGoogle Scholar
  10. Benton, M.J., and A.D. Walker. 1985. Palaeoecology, taphonomy, and dating of Permo-Triassic reptiles from Elgin, north-east Scotland. Palaeontology 28: 207–234.Google Scholar
  11. Benton, M.J., G. Warrington, A. Newell, and P.S. Spencer. 1994. A review of the British Mid Triassic tetrapod faunas. In In the Shadow of the Dinosaurs, ed. N.C. Fraser, and H.-D. Sues, 131–160. New York: Columbia University.Google Scholar
  12. Besairie, H. 1972. Géologie de Madagascar I. Les terraines sédimentaires. Annales Géologiques de Madagascar, Service des Mines 35: 1–463.Google Scholar
  13. Brazeau, M. 2011. Problematic character coding methods in morphology and their effects. Biological Journal of the Linnean Society 104: 489–498.CrossRefGoogle Scholar
  14. Bremer, K. 1994. Branch support and tree stability. Cladistics-the International Journal of the Willi Hennig Society 10: 295–304.CrossRefGoogle Scholar
  15. Butler, R.J., O.W.M. Rauhut, M.R. Stocker, and R. Bronowicz. 2014. Redescription of the phytosaurs Paleorhinus (“Francosuchus”) angustifrons and Ebrachosuchus neukami from Germany, with implications for Late Triassic biochronology. Zoological Journal of the Linnean Society 170: 155–208.CrossRefGoogle Scholar
  16. Butler, R., M. Ezcurra, F. Montefeltro, A. Samathi, and G. Sobral. 2015. A new species of basal rhynchosaur (Diapsida: Archosauromorpha) from the early Middle Triassic of South Africa, and the early evolution of Rhynchosauria. Zoological Journal of the Linnean Society 174: 571–588.CrossRefGoogle Scholar
  17. Chatterjee, S. 1980. The evolution of rhynchosaurs. Mémoires de la Société géologique de France 139: 57–65.Google Scholar
  18. Da Rosa, A.A.S. 2014. Geological context of the dinosauriform-bearing outcrops from the Triassic of Brazil. Journal of South American Earth Sciences 61: 108–119.CrossRefGoogle Scholar
  19. Da Silva, L.R., and S.F. Cabreira. 2009. Novo achado de Luangwa sudamericana Abdala & Teixeira, 2004 do Triássico Médio da Formação Santa Maria, Rio Grande do Sul, Brasil. Palaeontologia em Destaque 24: 23–24.Google Scholar
  20. Desojo, J.B., M.D. Ezcurra, and C.L. Schultz. 2011. An unusual new archosauriform from the Middle-Late Triassic of southern Brazil and the monophyly of Doswelliidae. Zoological Journal of the Linnean Society 161: 839–871.CrossRefGoogle Scholar
  21. Dilkes, D. 1998. The Early Triassic rhynchosaur Mesosuchus browni and the interrelationships of basal archosauromorph reptiles. Philosophical Transactions of the Royal Society of London Series B-Biological Sciences 353: 501–541.CrossRefGoogle Scholar
  22. Ezcurra, M.D., M.J. Trotteyn, L.E. Fiorelli, M.B. von Baczko, J.R.A. Taborda, M. Iberlucea, and J.B. Desojo. 2013. The oldest rhynchosaur from Argentina: a Middle Triassic rhynchosaurid from the Chañares Formation (Ischigualasto–Villa Unión Basin, La Rioja Province). Paläontologische Zeitschrift 88: 453–460.CrossRefGoogle Scholar
  23. Ezcurra, M.D., F.C. Montefeltro, and R.J. Butler. 2016. The early evolution of rhynchosaurs. Frontiers in Ecology and Evolution 3: 142.CrossRefGoogle Scholar
  24. Fiorelli, L.E., M.D. Ezcurra, E.M. Hechenleitner, E. Argañaraz, J.R.A. Taborda, M. Jimena Trotteyn, M.B. von Baczko, and J.B. Desojo. 2013. The oldest known communal latrines provide evidence of gregarism in Triassic megaherbivores. Scientific Reports 3: 3348.CrossRefGoogle Scholar
  25. Flynn, J.J., J.M. Parrish, L. Ranivoharimanana, W.F. Simpson, and A.R. Wyss. 2000. New traversodontids (Synapsida: Eucynodontia) from the Triassic of Madagascar. Journal of Vertebrate Paleontology 20: 422–427.CrossRefGoogle Scholar
  26. Flynn, J.J., S.J. Nesbitt, J.M. Parrish, L. Ranivoharimanana, and A.R. Wyss. 2010. A new taxon of Azendohsaurus (Archosauromorpha, Diapsida, Reptilia) from the Triassic Isalo Group of southwest Madagascar: part 1, cranium. Palaeontology 53: 669–688.CrossRefGoogle Scholar
  27. Goloboff, P., J. Farris, and K. Nixon. 2008. TNT, a free program for phylogenetic analysis. Cladistics 24: 774–786.CrossRefGoogle Scholar
  28. Gradstein, F.M., J.G. Ogg, M.D. Schmitz, and G.M. Ogg. 2012. The Geologic Time Scale 2012, 1144. Oxford: Elsevier.Google Scholar
  29. Horn, B.L.D., T.P. Melo, C.L. Schultz, R.P. Philipp, H.P. Kloss, and K. Goldberg. 2014. A new third-order sequence stratigraphic framework applied to the Triassic of the Paraná Basin, Rio Grande do Sul, Brazil, based on structural, stratigraphic and paleontological data. Journal of South American Earth Sciences 55: 123–132.CrossRefGoogle Scholar
  30. Hunt, A.P., and S.G. Lucas. 1991. A new rhynchosaur from West Texas (USA) and the biochronology of Late Triassic rhynchosaurs. Palaeontology 34: 927–938.Google Scholar
  31. Irmis, R.B., R. Mundil, J.W. Martz, and W.G. Parker. 2011. High-resolution U–Pb ages from the Upper Triassic Chinle Formation (New Mexico, USA) support a diachronous rise of dinosaurs. Earth and Planetary Science Letters 309: 258–267.CrossRefGoogle Scholar
  32. Kammerer, C.F., J.J. Flynn, L. Ranivoharimanana, and A.R. Wyss. 2010. The first record of a probainognathian (Cynodontia: Chiniquodontidae) from the Triassic of Madagascar. Journal of Vertebrate Paleontology 30: 1889–1894.CrossRefGoogle Scholar
  33. Langer, M.C. 2005. Studies on continental Late Triassic tetrapod biochronology. II. The Ischigualastian and a Carnian global correlation. Journal of South American Earth Sciences 19: 219–239.CrossRefGoogle Scholar
  34. Langer, M.C., and C.L. Schultz. 2000a. Rincossauros- herbívoros cosmopolitas do Triássico. In Paleontologia do Rio Grande do Sul, ed. M. Holz, and L.F. Roz, 246–272. Porto Alegre: CIGO/UFRGS.Google Scholar
  35. Langer, M.C., and C.L. Schultz. 2000b. A new species of the late Triassic rhynchosaur Hyperodapedon from the Santa Maria Formation of south Brazil. Palaeontology 43: 633–652.CrossRefGoogle Scholar
  36. Langer, M.C., M. Boniface, G. Cuny, and L. Barbieri. 2000. The phylogenetic position of Isalorhynchus genovefae, a Late Triassic rhynchosaur from Madagascar. Annales de Paléontologie 86: 101–127.CrossRefGoogle Scholar
  37. Langer, M.C., A.M. Ribeiro, C.L. Schultz, and J. Ferigolo. 2007. The continental tetrapod–bearing Triassic of South Brazil. Bulletin of the New Mexico Museum of Natural History and Science 41: 201–218.Google Scholar
  38. Leleu, S., and A.J. Hartley. 2010. Controls on the stratigraphic development of the Triassic Fundy Basin, Nova Scotia: implications for the tectonostratigraphic evolution of Triassic. Journal of the Geological Society, London 167: 437–454.CrossRefGoogle Scholar
  39. Long, J.A., and P.A. Murry. 1995. Late Triassic (Carnian and Norian) tetrapods from the Southwestern United States. Bulletin of the New Mexico Museum of Natural History and Science 4: 1–254.Google Scholar
  40. Lucas, S.G., and A.B. Heckert. 2002. The Hyperodapedon Biochron, Late Triassic of Pangea. Albertiana 27: 30–38.Google Scholar
  41. Lucas, S.G. 1998. Global Triassic tetrapod biostratigraphy and biochronology. Palaeogeography, Palaeoclimatology, Palaeoecology 143: 347–384.CrossRefGoogle Scholar
  42. Lucas, S.G. 2001. Age and correlation of Triassic tetrapod assemblages from Brazil. Albertiana 26: 13–20.Google Scholar
  43. Lucas, S.G., A.B. Heckert, and N. Hotton III. 2002. The rhynchosaur Hyperodapedon from the upper Triassic of Wyoming and its global biochronological significance. Bulletin of the New Mexico Museum of Natural History and Sciences 21: 149–156.Google Scholar
  44. Marsicano, C.A., R.B. Irmis, A.C. Mancuso, R. Mundil, and F. Chemale. 2015. The precise temporal calibration of dinosaur origins. In Proceedings of the National Academy of Science On-line first.Google Scholar
  45. Martínez, R.N., P.C. Sereno, O.A. Alcober, C.E. Colombi, P.R. Renne, I.P. Montañez, and B.S. Currie. 2011. A basal dinosaur from the dawn of the dinosaur era in southwestern Pangaea. Science 331: 206–210.CrossRefGoogle Scholar
  46. Martínez, R.N., C. Apaldetti, O.A. Alcober, C.E. Colombi, P.C. Sereno, E. Fernandez, P.S. Malnis, G.A. Correa, and D. Abelin. 2013. Vertebrate succession in the Ischigualasto Formation. Journal of Vertebrate Paleontology 32: 10–30.CrossRefGoogle Scholar
  47. Mietto, P., et al. 2012. The global boundary stratotype section and point (GSSP) of the Carnian Stage (Late Triassic) at Prati di Stuores/Stuores Wiesen section (southern Alps, NE Italy). Episodes 3: 414–430.Google Scholar
  48. Montefeltro, F., M.C. Langer, and C.L. Schultz. 2010. Cranial anatomy of a new genus of hyperodapedontine rhynchosaur (Diapsida, Archosauromorpha) from the upper Triassic of southern Brazil. Earth and Environmental Science Transactions of the Royal Society of Edinburgh 101: 27–52.CrossRefGoogle Scholar
  49. Montefeltro, F., J. Bittencourt, M.C. Langer, and C.L. Schultz. 2013. Postcranial anatomy of the hyperodapedontine rhynchosaur Teyumbaita sulcognathus (Azevedo and Schultz, 1987) from the Late Triassic of southern Brazil. Journal of Vertebrate Paleontology 33: 67–84.CrossRefGoogle Scholar
  50. Mukherjee, D., and S. Ray. 2014. A new Hyperodapedon (Archosauromorpha, Rhynchosauria) from the upper Triassic of India: implications for rhynchosaur phylogeny. Palaeontology 57: 1241–1276.CrossRefGoogle Scholar
  51. Nesbitt, S. 2005. Stratigraphy and tetrapod fauna of major quarries in the Moenkopi Formation (Early-Middle Triassic) along the Little Colorado River of northern Arizona. Bulletin of the Mesa Southwest Museum 11: 18–33.Google Scholar
  52. Nesbitt, S.J., and R.L. Whatley. 2004. The first discovery of a rhynchosaur from the upper Moenkopi Formation (Middle Triassic) of northern Arizona. PalaeoBios 24: 1–10.Google Scholar
  53. Nesbitt, S.J., J.J. Flynn, A.C. Pritchard, J.M. Parrish, L. Ranivoharimanana, and A.R. Wyss. 2015. Postcranial osteology of Azendohsaurus madagaskarensis (?Middle to Upper Triassic, Isalo Group, Madagascar) and its systematic position among stem archosaur reptiles. Bulletin of the American Museum of Natural History 398: 1–126.CrossRefGoogle Scholar
  54. Philipp, R.P., H. Closs, C.L. Schultz, M. Basei, B.L.D. Horn, and M.B. Soares. 2013. Proveniência por U-Pb LA-ICP-MS em zircão detrítico e idade de deposição da Formação Santa Maria, Triássico da Bacia do Paraná, RS: evidências da estruturação do Arco do Rio Grande. In Anais do VIII Symposium International on Tectonics & XIV Simpósio Nacional de Estudos Tectónicos, 154–157. Cuiabá.Google Scholar
  55. Prevosti, F., and M. Chemisquy. 2010. The impact of missing data on real morphological phylogenies: influence of the number and distribution of missing entries. Cladistics 26: 326–339.CrossRefGoogle Scholar
  56. Ramezani, J., D.E. Fastovsky, and S.S. Bowring. 2014. Revised chronostratigraphy of the lower Chinle Formation strata in Arizona and New Mexico (USA): high-precision U-Pb geochronological constraints on the Late Triassic evolution of dinosaurs. American Journal of Science 314: 981–1008.CrossRefGoogle Scholar
  57. Razafimbelo, E. 1987. Le basin de Morondava (Madagascar). Synthèse géologique et structurale. Ph.D. dissertation. Strasbourg, Université Louis Pasteur. p. 189.Google Scholar
  58. Schultz, C.L. 1995. Subdivisão do Triássico do RS com base em macrofósseis: problemas e perspectivas. Comunicações do Museu de Ciências e Tecnologia, UBEA/PUCRS, Série Ciências da Terra 1: 25–32.Google Scholar
  59. Schultz, C.L., and S.A.K. Azevedo. 1990. Dados preliminares sobre a ocorrência de uma nova forma de rincossauro para o Triássico do Rio Grande do Sul-Brasil. Paula-Coutiana 4: 35–44.Google Scholar
  60. Siddall, M.E. 2002. Measures of support. In Techniques in molecular systematics and evolution, ed. R. DeSalle, G. Giribet, and W.C. Wheeler, 80–101. Basel: Birkhauser Verlag.CrossRefGoogle Scholar
  61. Soares, M.B., C.L. Schultz, and B.L.D. Horn. 2011. New information on Riograndia guaibensis Bonaparte, Ferigolo & Ribeiro, 2001 (Eucynodontia, Tritheledontidae) from the Late Triassic of southern Brazil: anatomical and biostratigraphic implications. Anais da Academia Brasileira de Ciências 83: 329–354.CrossRefGoogle Scholar
  62. Spielmann, J.A., S.G. Lucas, and A.P. Hunt. 2013. The first Norian (Revueltian) rhynchosaur: Bull Canyon Formation, New Mexico, USA. New Mexico Museum of Natural History and Science Bulletin 61: 562–566.Google Scholar
  63. Wilkinson, M. 2003. Missing entries and multiple trees: instability, relationships, and support in parsimony analysis. Journal of Vertebrate Paleontology 23: 311–323.CrossRefGoogle Scholar
  64. Zerfass, H., E.L. Lavina, C.L. Schultz, A.G.V. Garcia, U.F. Faccini, and F. Chemale Jr. 2003. Sequence stratigraphy of continental Triassic strata of southernmost Brazil: a contribution to Southwestern Gondwana palaeogeography and palaeoclimate. Sedimentary Geology 161: 85–105.CrossRefGoogle Scholar

Copyright information

© Paläontologische Gesellschaft 2016

Authors and Affiliations

  1. 1.Departamento de Paleontologia e Estratigrafia, Instituto de GeociênciasUniversidade Federal do Rio Grande do SulPorto AlegreBrazil
  2. 2.Departamento de Biologia, Faculdade de Filosofia Ciências e Letras de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
  3. 3.Departamento de Biologia e Zootecnia, Faculdade de EngenhariaUniversidade Estadual PaulistaIlha SolteiraBrazil

Personalised recommendations