Systematics of an Oligocene-Aged Fossil Snake Assemblage from the White River Formation, Wyoming

• Author / Creator

  Croghan, Jasmine A.

• Extinct snake taxa are primarily recognized from isolated vertebrae. A new specimen from the Oligocene of Wyoming provides a rare opportunity to examine four nearly complete and articulated fossil snakes. Informally assigned previously to the ‘erycine’ vertebral form taxa Ogmophis and Calamagras, a comparison reveals that the diagnostic morphology of both genera are present in a single individual of the new specimen, invalidating these assignments. A new taxon, Congerophis lego is described and erected, and its phylogenetic relationships are tested using two existing morphological datasets of all snakes and of the ‘Erycinae.’ Congerophis lego is found to be in the sister-group position to the New World ‘erycine’ Charina. When Charina and the Old World ‘erycine’ Eryx are scored separately and analyzed with relevant outgroup taxa, the subfamily is found to be non-monophyletic. The new subfamily Charininae, inclusive of Charina and Congerophis, is erected, and the ‘Erycinae’ is redefined as monogeneric.

• Subjects / Keywords

  • Systematics
  • Vertebral Form-Taxa
  • Congerophis
  • Snake
  • Charininae
  • Phylogeny
  • Ungaliophiinae
  • Assemblage
  • Calamgras
  • Erycinae
  • Ogmophis

• Graduation date

  Spring 2014

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3HM2G

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.