Comparative anatomy and osteohistology of hyperelongate neural spines in the sphenacodontids Sphenacodon and Dimetrodon (Amniota: Synapsida)

  title={Comparative anatomy and osteohistology of hyperelongate neural spines in the sphenacodontids Sphenacodon and Dimetrodon (Amniota: Synapsida)},
  author={Adam K. Huttenlocker and Elizabeth Rega and Stuart S. Sumida},
  journal={Journal of Morphology},
Osteohistological investigations of hyperelongate vertebral spinous processes (neural spines) are presented to elucidate previously unknown aspects of dorsal sail form and function in two, closely related genera of “sail‐backed” synapsids: Sphenacodon and Dimetrodon. Although recent and classic surveys of bone histology in extinct vertebrates have sampled the genus Dimetrodon, new sectioning of Sphenacodon material allows a comparative analysis of these structures among Sphenacodontidae for the… 

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