Ichthyosaurian relationships illuminated by new primitive skeletons from Japan

@article{Motani1998IchthyosaurianRI,
  title={Ichthyosaurian relationships illuminated by new primitive skeletons from Japan},
  author={Ryosuke Motani and Nachio Minoura and Tatsuro Ando},
  journal={Nature},
  year={1998},
  volume={393},
  pages={255-257}
}
The Ichthyosauria is a group of reptiles with fish-shaped bodies from the Mesozoic (65–250 million years ago),. Their secondary adaptations to aquatic life have obscured their ancestral features,, and basal ichthyosaurs, which would be expected to retain these ancestral features (plesiomorphies), are poorly represented in the fossil record. As a result, their relationships to other amniotes have been controversial for over 180 years,. New specimens of Utatsusaurus hataii from the Lower Triassic… 

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