A new transitional sauropodomorph dinosaur from the Early Jurassic of South Africa and the evolution of sauropod feeding and quadrupedalism

@article{Yates2009ANT,
  title={A new transitional sauropodomorph dinosaur from the Early Jurassic of South Africa and the evolution of sauropod feeding and quadrupedalism},
  author={Adam Michael Yates and Matthew F. Bonnan and Johann Neveling and Anusuya Chinsamy and Marc G. Blackbeard},
  journal={Proceedings of the Royal Society B: Biological Sciences},
  year={2009},
  volume={277},
  pages={787 - 794}
}
Aardonyx celestae gen. et sp. nov. is described from the upper Elliot Formation (Early Jurassic) of South Africa. It can be diagnosed by autapomorphies of the skull, particularly the jaws, cervical column, forearm and pes. It is found to be the sister group of a clade of obligatory quadrupedal sauropodomorphs (Melanorosaurus + Sauropoda) and thus lies at the heart of the basal sauropodomorph–sauropod transition. The narrow jaws of A. celestae retain a pointed symphysis but appear to have lacked… 

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