Fusion of sacrals and anatomy in Champsosaurus (Diapsida, Choristodera)

@article{Katsura2007FusionOS,
  title={Fusion of sacrals and anatomy in Champsosaurus (Diapsida, Choristodera)},
  author={Yoshihiro Katsura},
  journal={Historical Biology},
  year={2007},
  volume={19},
  pages={263 - 271}
}
Sacral centra are occasionally fused with or without severe deformation in Champsosaurus (Diapsida, Choristodera). The sympatrical occurrence of fusion and non-fusion of sacra in adults through their evolution questions that sacral fusion represents the final form of a simple ontogenetic change or specific variation. Females are proposed to possess more robust limb bones than males because they are considered to have been more terrestrial due to the nesting behaviour on land. The coincidental… 
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