A Middle Triassic stem-turtle and the evolution of the turtle body plan

@article{Schoch2015AMT,
  title={A Middle Triassic stem-turtle and the evolution of the turtle body plan},
  author={Rainer R. Schoch and Hans‐Dieter Sues},
  journal={Nature},
  year={2015},
  volume={523},
  pages={584-587}
}
The origin and early evolution of turtles have long been major contentious issues in vertebrate zoology. This is due to conflicting character evidence from molecules and morphology and a lack of transitional fossils from the critical time interval. The ∼220-million-year-old stem-turtle Odontochelys from China has a partly formed shell and many turtle-like features in its postcranial skeleton. Unlike the 214-million-year-old Proganochelys from Germany and Thailand, it retains marginal teeth and… 
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