Cretaceous choristoderan reptiles gave birth to live young

@article{Ji2010CretaceousCR,
  title={Cretaceous choristoderan reptiles gave birth to live young},
  author={Qiang Ji and Xiaocong Wu and Yen-nien Cheng},
  journal={Naturwissenschaften},
  year={2010},
  volume={97},
  pages={423-428}
}
Viviparity (giving birth to live young) in fossil reptiles has been known only in a few marine groups: ichthyosaurs, pachypleurosaurs, and mosasaurs. Here, we report a pregnant specimen of the Early Cretaceous Hyphalosaurus baitaigouensis, a species of Choristodera, a diapsid group known from unequivocal fossil remains from the Middle Jurassic to the early Miocene (about 165 to 20 million years ago). This specimen provides the first evidence of viviparity in choristoderan reptiles and is also… 
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