Comments on additional dinosaur specimens from the Janner site (Upper Triassic of the Paraná Basin), southern Brazil

Rodrigo Temp Müller; Maurício Silva Garcia; Flávio Augusto Pretto

doi:10.4072/rbp.2020.3.02

Authors

Rodrigo Temp Müller Centro de Apoio à Pesquisa Paleontológica, Universidade Federal de Santa Maria, Rua Maximiliano Vizzotto, 598, 97230-000, São João do Polêsine, RS, Brazil.
Maurício Silva Garcia Laboratório de Paleobiodiversidade Triássica, Departamento de Ecologia e Evolução, Universidade Federal de Santa Maria, Av. Roraima, 1000, 97105-900, Santa Maria, RS, Brazil.
Flávio Augusto Pretto Centro de Apoio à Pesquisa Paleontológica, Universidade Federal de Santa Maria, Rua Maximiliano Vizzotto, 598, 97230-000, São João do Polêsine, RS, Brazil.

DOI:

https://doi.org/10.4072/rbp.2020.3.02

Abstract

The Janner site (Upper Triassic of Southern Brazil) has been intensely explored, yielding constant new findings in recent years. Among these some fragmentary dinosaur specimens still not published were sampled. In this contribution, we describe these specimens, which represent five individuals, in order to increase our understanding on the anatomy of the dinosaurs that compose the paleofauna of the Janner site. The specimen CAPPA/UFSM 0270 is comprised of a series of six articulated presacral vertebrae, plus two isolated vertebrae associated with a right femur. UFRGS-PV-1232-T comprises a sacrum and a left ilium. CAPPA/UFSM 0271 comprises a right humerus that lacks the middle portion of the diaphysis. CAPPA/UFSM 00272 and 2073 are both comprised of an isolated femur each. The fragmentary condition of the materials hampers any less inclusive assignation. However, the morphology of the elements resembles those of coeval dinosaurs. Furthermore, the new specimens increase our knowledge on the morphology of some structures poorly understood from the dinosaurs of Janner site, such as the hindlimb and axial skeleton.

Keywords: Hyperodapedon Assemblage Zone, Carnian, Saurischia, Sauropodomorpha, Archosauria, Dinosauria.

O sítio Janner (Triássico Superior do Sul do Brasil) tem sido explorado intensamente, produzindo constantes novos achados nos últimos anos. Dentre estes, restos de dinossauros ainda não publicados foram recuperados. Nesta contribuição nós descrevemos estes espécimes, que totalizam cinco indivíduos, com o objetivo de aumentar o entendimento sobre a anatomia e amostragem de dinossauros que compõem o conteúdo paleofaunístico do sítio Janner. O espécime CAPPA/UFSM 0270 é composto por uma série de seis vértebras pré-sacrais articuladas, além de duas vértebras isoladas e um fêmur direito. UFRGS-PV-1232-T corresponde a um sacro e um ílio esquerdo. CAPPA/UFSM 0271 compreende um úmero direito que carece de sua diáfise. CAPPA/UFSM 0272 e 0273 compreendem um fêmur isolado cada. A condição fragmentária dos espécimes impede uma atribuição taxonômica menos inclusiva. Porém, a morfologia dos elementos lembra a de dinossauros coevos. Além disso, os novos espécimes aumentam nosso conhecimento sobre a morfologia de estruturas ainda pouco conhecidas de dinossauros do sítio Janner, como o membro anterior e o esqueleto axial.

Palavras-chave: Zona de Associação de Hyperodapedon, Carniano, Saurischia, Sauropodomorpha, Archosauria, Dinosauria.

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