Research paper Evolutionary history of the Persian squirrel (Sciurus anomalus): It emerged on the Eurasian continent in the Miocene Marzieh Asadi Aghbolaghi a, c , Faraham Ahmadzadeh a, * , Bahram H. Kiabi b , Nusha Keyghobadi c a Department of Biodiversity and Ecosystem Management, Environmental Sciences Research Institute, Shahid Beheshti University, G.C., Tehran, Iran b Department of Animal Sciences and Marine Biology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, G. C., Tehran, Iran c Department of Biology, The University of Western Ontario, London, ON N6A 5B7, Canada article info Article history: Received 28 December 2019 Received in revised form 27 April 2020 Accepted 28 April 2020 Available online 5 May 2020 Corresponding Editor: J. Ziermann Keywords: Sciurus anomalus Sciurus vulgaris Sciurus lis Mitochondrial genes Nuclear genes abstract The Persian squirrel (Sciurus anomalus) is limited to the Irano-Anatolian region of western Asia. The evolutionary history and phylogenetic status of the Persian squirrel are ambiguous. Here, we present a molecular phylogeny using mitochondrial and nuclear genes (D-loop noncoding region, Cyt b, COI, Cmyc, and Rag1) for S. anomalus and other Sciurus species. Our analyses revealed three major clades comprising (i) Sciurus species in North America, (ii) Sciurus vulgaris and Sciurus lis in Eurasia and (iii) S. anomalus in western Asia. For mitochondrial and nuclear genes, uncorrected genetic distances between S. anomalus and each of the two other clades were similar. We conclude that the divergence of S. anomalus from the ancestor of New World species occurred on the Eurasian continent during the Miocene period 10 Mya (HPD: 11-8 Mya), with the ancestral New World species then moving from Eurasia through Beringia to North America. During the Pleistocene period S. anomalus gradually became widespread in association with prevalent woodlands throughout the Irano-Anatolian terrain and the eastern coast of the Medi- terranean Sea. Today we find this species in fragmented forests in and around the Mediterranean Sea, Anatolia (Turkey) and in the Zagros Mountains (western Iran). © 2020 Elsevier GmbH. All rights reserved. 1. Introduction Sciurini is a tribe that includes five genera (Sciurus, Tamiasciurus, Microsciurus, Rheithrosciurus, Syntheosciurus) and about forty spe- cies of squirrels, mostly from the Americas (Nowak, 1999; Wilson & Reeder, 2005). Two genera of the Sciurini tribe are found in Eurasia (Sciurus and Rheithrosciurus), but only Sciurus is widely distributed throughout this region. The genus Sciurus (tree squirrels) Linnaeus, 1758, comprises 28 tree dwelling squirrel species which inhabit deciduous and conif- erous forests throughout the Palearctic, Nearctic and Neotropical regions (Thorington & Hoffmann 2005; Hafner et al. 1994). In Eurasia, three species are currently present: the red squirrel, Sciurus vulgaris Linnaeus, 1758, the Persian squirrel (or Caucasian squirrel), Sciurus anomalus Gueldenstaedt, 1785, and the Japanese squirrel Sciurus lis Temminck, 1844 (Gurnell, 1987; Gavish & Gurnell, 1999; Marder et al., 2011; Tagliacozzo et al., 2016; Sato, 2017). S. vulgaris is found throughout northern Palearctic forests from Iberia and Great Britain, east to Russia’s Kamchatka Peninsula and Sakhalin Island, and to Hokkaido in Japan, as far south as the Black Sea and northern Mediterranean Sea (although S. vulgaris includes more than 40 subspecies, there is recent genetic evidence that some of them have evolved into separate species like “Sciurus meridionalis”; Wilson & Reeder, 2005; Dozi eres et al., 2012; Liu et al., 2014; Madsen et al., 2015; Wauters et al., 2017). S. anomalus is distributed from Greece throughout coniferous and oak forests in Turkey, Armenia, Georgia, Azerbaijan, Iran, Iraq, Palestine, Jordan, Lebanon and Syria (Hatt 1959; Osborn 1964; Harrison & Bates 1991; € Ozkurt et al. 1999; Amr et al. 2006; Arslan et al. 2008; Thorington et al. 2012; Khalili et al. 2016; Koprowski et al. 2016). S. lis is endemic to Japan and its range includes the islands of Honshu, Shikoku, and Kyushu (Harrison & Bates 1991). The three Eurasian Sciurus species can be distinguished morphologically. S. anomalus is recognized by the absence of ear tufts, a trait present in both S. vulgaris and S. lis (Thorington & Hoffmann, 2005; Arslan et al., 2008). S. anomalus is also smaller than the other two species with a distinct coat coloration: the * Corresponding author. E-mail address: f_ahmadzade@sbu.ac.ir (F. Ahmadzadeh). Contents lists available at ScienceDirect Zoologischer Anzeiger journal homepage: www.elsevier.com/locate/jcz https://doi.org/10.1016/j.jcz.2020.04.007 0044-5231/© 2020 Elsevier GmbH. All rights reserved. Zoologischer Anzeiger 287 (2020) 17e24