Abstract
Two localities in the Panaca Formation, Meadow Valley, Lincoln County, Nevada, have produced squamate remains that date to 4.9–4.7 Ma. Included are fossil maxillae of Crotaphytus sp. (Collared Lizards) and a dentary of Gambelia sp. (Leopard Lizards). To identify these fossils, diagnostic dental characters were used to distinguish the two genera. The toothrow of Crotaphytus exhibits wide, robust teeth and consists of mostly tricuspid teeth that show little or no recurvature. Gambelia dentition differs in having highly recurved, parallel-sided teeth throughout the toothrow, which contains more unicuspid than tricuspid teeth. Published records of valid Crotaphytus date to the middle Pliocene (3.7–3.1 Ma) and Gambelia date to the early to middle Pliocene (4.18–3.58 Ma). The Panaca Formation fossils described herein mark the oldest known record of both taxa.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
