Chinlechelys from the Upper Triassic of New Mexico, USA, and the origin of turtles

  title={Chinlechelys from the Upper Triassic of New Mexico, USA, and the origin of turtles},
  author={Asher Lichtig and Spencer G. Lucas},
  journal={Palaeontologia Electronica},
Chinlechelys tenertesta is a turtle from the Upper Triassic Bull Canyon Formation of the Chinle Group of eastern New Mexico, USA, which has largely been ignored in recent studies of the phylogenetic position of turtles (Testudinata) within the Tetrapoda. Here, we present the first comprehensive description of the morphology of Chinlechelys tenertesta and reaffirm its unequivocal support for the composite model of costal bone formation in turtles. We also document the presence in Chinlechelys… 
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