Ermakov O.A., Brandler O.V., Ivanov A.Yu., Ivanova A.D., Kesyan A.A., Khalidov A.Kh., Lotiev K.Yu., Lukonina S.A., Tsapko V., Titov S.V. 2023. Riverine barriers and the geographical variation in little ground squirrel Spermophilus pygmaeus (Sciuridae, Rodentia) based on the mitochondrial cytochrome b sequences // Russian J. Theriol. Vol.22. No.1. P.24–31 [in English].
Oleg A. Ermakov [email@example.com], Alexandr Yu. Ivanov [firstname.lastname@example.org], Svetlana A. Lukonina [email@example.com], Sergey V. Titov [firstname.lastname@example.org], Penza State University, Krasnaya 40, Penza 440026, Russia; Oleg V. Brandler [email@example.com], Koltzov Institute of Developmental Biology of Russian Academy of Sciences, Vavilova 26, Moscow 119334, Russia; Anastasiya D. Ivanova [Sciuridae2012@yandex.ru], Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, Vavilova 32, Moscow 119991, Russia; Artem A. Kesyan [firstname.lastname@example.org], Arslan Kh. Khalidov [email@example.com], Dagestan Anti-Plague Station, Gagarina 13, Makhachkala 367015, Russia; Konstantin Yu. Lotiev [firstname.lastname@example.org], Sochi National Park, Moskovskaya 21, Sochi 354000, Russia, Kh. Ibragimov Complex Institute of Russian Academy of Sciences, Staropromyslovskoe shosse 21, Grozny 364051, Chechnya, Russia, National Park “Kislovodskiy“, Kurortny boulevard 21, Kislovodsk 357700, Russia; Nikolay V. Tsapko [email@example.com], Stavropol Anti-Plague Institute, Sovetskaya 13-15, Stavropol 355090, Russia.
ABSTRACT. Little ground squirrel (Spermophilus pygmaeus) typically inhabit semi-deserts and dry steppes of the European plains and Kazakhstan. Range-wide latitudinal distribution along with major river separation zones makes this species a proper model for testing the riverine barrier hypothesis. For the first time, we have evaluated genetic variation in little ground squirrel populations throughout its range based on the analysis of cytochrome b gene sequences. A high level of genetic diversity (4.9%) among “western” and “eastern” populations of the little ground squirrel has evidenced the Volga River to be an effective biogeographic barrier. A barrier role of the Ural River is expressed to a lesser extent, and the Don River has neither effect on the restriction to gene flow and phylogeographic structure. The genetic diversity data has confirmed the hypothesis on S. pygmaeus speciation in the long-term Ciscaucasia refugium, and the appearance of the mountain ground squirrel (S. p. musicus) in the Middle Pleistocene.
KEY WORDS: ground squirrels, genetic diversity, isolation, phylogeography.