Ground squirrels of the genus Spermophilus from the Pleistocene and Holocene localities of the Middle and South Urals and Trans-Urals region: the dental features

ABSTRACT

The dental features of fossil Spermophilus from eleven Pleistocene and Holocene localities of the Middle and South Urals and Trans-Urals region are described. The comparison with the recent species S. major, S. fulvus and S. pygmaeus from the same region was carried out. The most important features of the recent and fossil S. pygmaeus are: small and medium sizes; metaloph of P4-M2 bear constrictions or interruptions, metaconule is well pronounced and rounded; anterostyle often is well developed in P4; high frequency of meso- and metastylid in m1-3. In M3 the anterior inner and posterior roots are close together and tend to merge with each other in their upper parts. Also, S. major was a part of the Late Pleistocene and Holocene faunas. The most important features of S. major are: medium and large sizes; a small number of P4-M2 with the occlusal cusps, among them the most significant is the presence of parastyle; in m1-2 mesostylid commonly occurs. The tendency to complication of the root part of M3 of S. superciliosus is revealed from Late Pleistocene to Holocene. The comparison with the fossil S. superciliosus from Eastern Europe was carried out. No significant differences between S. superciliosus and S. major were found.

KEYWORDS:

• Genus Spermophilus
• teeth
• morphology
• Late Pleistocene
• Holocene
• Urals

Acknowledgments

We are grateful to Maxim V. Sinitsa (Ural Federal University) for discussions on fossil ground squirrels. Special thanks to the anonymous reviewers their helpful comments and suggestions.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was performed within the frameworks of state contract with the Institute of Plant and Animal Ecology, Ural Branch, Russian Academy of Sciences. The research was supported by Act 211 of the Government of the Russian Federation, contract No. 02.A03.21.0006. This work was supported by the International Union of Quaternary research, Commission ‘Humans and Biosphere’, under Grant 1606.