Naturwissenschaften

, Volume 98, Issue 12, pp 1035–1040

New stem-sauropodomorph (Dinosauria, Saurischia) from the Triassic of Brazil

  • Sergio F. Cabreira
  • Cesar L. Schultz
  • Jonathas S. Bittencourt
  • Marina B. Soares
  • Daniel C. Fortier
  • Lúcio R. Silva
  • Max C. Langer
Original Paper

Abstract

Post-Triassic theropod, sauropodomorph, and ornithischian dinosaurs are readily recognized based on the set of traits that typically characterize each of these groups. On the contrary, most of the early members of those lineages lack such specializations, but share a range of generalized traits also seen in more basal dinosauromorphs. Here, we report on a new Late Triassic dinosaur from the Santa Maria Formation of Rio Grande do Sul, southern Brazil. The specimen comprises the disarticulated partial skeleton of a single individual, including most of the skull bones. Based on four phylogenetic analyses, the new dinosaur fits consistently on the sauropodomorph stem, but lacks several typical features of sauropodomorphs, showing dinosaur plesiomorphies together with some neotheropod traits. This is not an exception among basal dinosaurs, the early radiation of which is characterized by a mosaic pattern of character acquisition, resulting in the uncertain phylogenetic placement of various early members of the group.

Keywords

Dinosauria, Late Triassic Santa Maria Formation Archosauria Phylogeny 

Supplementary material

114_2011_858_MOESM1_ESM.pdf (1.3 mb)
ESM 1(PDF 1348 kb)

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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Sergio F. Cabreira
    • 1
  • Cesar L. Schultz
    • 2
  • Jonathas S. Bittencourt
    • 3
  • Marina B. Soares
    • 2
  • Daniel C. Fortier
    • 4
  • Lúcio R. Silva
    • 1
  • Max C. Langer
    • 3
  1. 1.Museu de Ciências NaturaisUniversidade Luterana do Brasil (ULBRA)CanoasBrazil
  2. 2.Departamento de Paleontologia e Estratigrafia, Instituto de GeociênciasUniversidade Federal do Rio Grande do Sul (UFRGS)Porto AlegreBrazil
  3. 3.Laboratório de Paleontologia de Ribeirão Preto, FFCLRPUniversidade de São PauloRibeirão PretoBrazil
  4. 4.Departamento de GeologiaUFMGBelo HorizonteBrazil

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