(Qiu, Huang & Guo, 1987) (Equidae, Hipparionini) from the Late Pliocene

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A Bollettino della Società Paleontologica Italiana, 57 (2), 2018, 125-132. Modena

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S. P. I.

The first occurrence of Plesiohipparion huangheense (Qiu, Huang & Guo, 1987) (Equidae, Hipparionini) from the late Pliocene of India

Advait Mahesh Jukar, Boyang Sun & Raymond Louis Bernor

A.M. Jukar, Department of Environmental Science and Policy, George Mason University, Fairfax VA 22030, USA; Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington D.C. 20013, USA; [email protected] B. Sun, Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, CHN; University of Chinese Academy of Sciences, Beijing 100039, CHN; College of Medicine, Department of Anatomy, Laboratory of Evolutionary Biology, Howard University, Washington D.C. 20059, USA; [email protected] R.L. Bernor, College of Medicine, Department of Anatomy, Laboratory of Evolutionary Biology, Howard University, Washington D.C. 20059, USA; [email protected]

KEY WORDS - Asia, Cenozoic, Biogeography, Hipparionine horses, Dispersal.

ABSTRACT - Hipparionine horses are well known from the Miocene of the Indian subcontinent and include several lineages. Their Pliocene record is poorly known in comparison. Here we report the first record of a hipparionine horse lineage,Plesiohipparion huangheense, from late Pliocene sediments in the Siwalik Hills in N.W. India. This species was formerly known from the late Pliocene of Northern China and the earliest Pleistocene of Turkey. This new occurrence presents us with two dispersal hypotheses for this species. By analyzing faunal connections across Eurasia, we conclude that P. huangheense most likely dispersed from China to India and Turkey from north of the Tibetan Plateau.

RIASSUNTO - [Prima segnalazione di Plesiohipparion huangheense (Qiu, Huang & Guo, 1987) (Equidae, Hipparionini) dal Pliocene superiore dell’India] - I cavalli ipparionini sono ben conosciuti nel Miocene del Subcontinente Indiano, dove sono presenti con diverse line evolutive. Per contro, il loro registro fossile pliocenico è poco conosciuto. Questa nota riporta la prima segnalazione di un equide ipparionino, Plesiohipparion huangheense, da sedimenti del Pliocene superiore delle Siwalik Hills, nell’India nord-occidentale. Detta specie era nota in precedenza dal Pliocene superiore della Cina settentrionale e dal Pleistocene inferiore basale della Turchia. Questo nuovo ritrovamento suggerisce due possibili ipotesi di ricostruzione dello scenario di dispersione della specie. Alla luce di una discussione sulle connessioni faunistiche entro il continente eurasiatico, lo scenario più probabile per la dispersione di P. huangheense dalla Cina verso l’India e la Turchia è attraverso una via sita a nord dell’Altipiano Tibetano.

INTRODUCTION in India generates new hypotheses for the dispersal of P. huangheense (Qiu, Huang & Guo, 1987) from China to Hipparionine horses have been known from the Indian Turkey, and increases our understanding of the diversity of Subcontinent since the early part of the 19th century large mammals in the Indian Subcontinent in the Pliocene. (Lydekker, 1882). A recent revision of late Miocene hipparionine horses recognized a diverse evolutionary series of species from the Potwar Plateau, Pakistan: GEOLOGY AND AGE Cormohipparion sp. Skinner & MacFadden, 1977, Sivalhippus nagriensis (Hussain, 1971), S. theobaldi Between 1834 and 1837, Captain Proby Cautley and (Lydekker, 1877), S. perimensis (Pilgrim, 1910), S. anwari Dr. Hugh Falconer, along with other military officers, Wolf, Bernor & Hussain, 2013, and Cremohipparion discovered several fossil deposits between the rivers antelopinum (Falconer & Cautley, 1849) (Wolf et al., Yamuna and Sutlej in Northwest India (Murchison, 1868). 2013). Pliocene hipparionines from South Asia have Their vast collection, including NHMUK PV OR 15790, been referred to “Hipparion” de Christol, 1832 s.l. on the was later shipped to and housed at the Natural History Potwar Plateau (Barry et al., 1982), and Hippotherium Museum in London. These early collectors did not keep antilopinum Falconer & Cautley, 1849, “Hipparion” detailed records of where the discoveries were made, theobaldi (Lydekker, 1877), “Hipparion” antelopinum therefore, giving us only an approximate estimate of the (Falconer & Cautley, 1849), and “Hipparion” sp. in the stratigraphic position and age of this specimen. However, Indian Siwaliks (Badam, 1979; Nanda, 1979; Moigne et historical records about the search area (Murchison, 1868) al., 2016). Here we report a Pliocene-aged mandibular offer clear insights into the age of the specimen. fragment of a hipparionine horse collected by P. Cautley The British explorers surveyed an area in the in the 1830s in India that does not belong to any known Himalayan foothills, between the rivers Yamuna in the genus from the Indian Subcontinent but represents east and Sutlej in the west, referred to as the Siwalik Plesiohipparion huangheense, a species known from Hills (Murchison, 1868). Modern palaeomagnetic studies Northern China and Turkey. The presence of the species have shown that fossiliferous sediments in this search

ISSN 0375-7633 doi:10.4435/BSPI.2018.08 126 Bollettino della Società Paleontologica Italiana, 57 (2), 2018

Fig. 1 - Location map of the area surveyed by 19th century British explorers, between the rivers Sutlej and Yamuna, showing the extent of the different beds exposed. a) The region around the town of Chandigarh. b) The region around the modern Saketi Fossil Park near the Yamuna River. c-e) Different upper Pliocene exposures where hipparionine horse fossils have been found. area range in age from the late Pliocene (~3.6 Ma) to with greyish and reddish sandstones (Nanda, 1981; the early middle Pleistocene (~0.6 Ma) representing the Chapon Sao et al., 2016b). Upper Siwalik beds and consist of three lithostratigraphic units, the Boulder Conglomerate at the top laid down time-transgressively between 1.7 and 0.6 Ma, the Pinjor MATERIALS AND METHODS Formation (2.58-0.6 Ma) and Pre-Pinjor Beds (3.6-2.58 Ma) (Azzaroli & Napoleone, 1982; Ranga Rao et al., 1995; We compare the specimens of Plesiohipparion Kumaravel et al., 2005; Chapon Sao et al., 2016a). Middle huangheense described herein to our available database and Lower Siwalik exposures have not yielded many including a relevant group of late Miocene and Pliocene fossils (Nanda et al., 1991). Exposures of these sediments Old World hipparionine taxa (localities and ages discussed in the historical survey area are shown in Fig. 1a-b. in several previous studies: Bernor et al., 1988, 1993, In the Indian Subcontinent, hipparionine horses are 1996, 1997, 2003a,b, 2011). Tooth measurements and abundant in the late Miocene, rare in the Pliocene, and description follow the standard defined in Bernor et al. absent in the Pleistocene where they are replaced by (1997). Since the nomen Hipparion has been used in a Equus (Patnaik, 2013). In the area surveyed by the British variety of ways by different authors, we follow herein explorers, hipparionine specimens have been found in characterizations and definitions for hipparionine horses three geographic areas: 1) near the town of Masol; 2) near as provided in Bernor et al. (1996, 1997), and that the village of Khetpurali; and 3) near the town of Saketi “Hipparion” is a general taxonomic term for hipparionine (Fig. 1c-e). Sediments at Masol have been dated to ~2.9- horses not referable to the genus Hipparion sensu stricto 2.6 Ma (Chapon Sao et al., 2016a), while at Khetpurali, (s.s.) (Bernor et al., 2016). hipparionine horses have been found in deposits between In this study, we report three specimens, one from India 3.3 and 2.58 Ma (Nanda, 1981; Tandon et al., 1984), and that represents a novel occurrence of Plesiohipparion between 3.6 and 3.0 Ma near the town of Saketi (Azzaroli huangheense, and two comparative specimens, one & Napoleone, 1982; Mishra et al., 2013). Thus, it is most from Northern China, and the other from Turkey. The likely that NHMUK PV OR 15790 is late Pliocene in Indian specimen, NHMUK PV OR 15790, a mandibular age (3.6 Ma to 2.6 Ma), correlative with European MN fragment with p4-m1 (Fig. 2), is a part of the Falconer unit 16, and the Mazegouan horizons in the Yushe Basin, and Cautley collection of Siwalik vertebrates accessioned China (Opdyke et al., 2013). These Pliocene beds typically in the Earth Science collections at the Natural History consist of variegated and grey mudstones, interspersed Museum, London, UK (NHMUK). The Chinese specimen, A.M. Jukar et alii - Pliocene Plesiohipparion from India 127

THP10097, a complete mandible (Fig. 2), is accessioned Paleontology and Paleoanthropology, Chinese Academy in the research collections at the Tianjin Natural History of Sciences. Museum, Tianjin, China (THP), and the Turkish specimen, HU9102, is a mandibular fragment with p3-m3 (Fig. 2), Type locality - Dongyaocun, Pucheng County, Shaanxi accessioned in the research collections in the Laboratory Province, China. of Evolutionary Biology, Department of Anatomy, College of Medicine, Howard University, Washington D.C., USA Known distribution - Gaotege, Yushe, Shaanxi, and (HU). All measurements were taken using digital calipers Pucheng in Northern China, Gülyazi in Turkey and N.W. to the nearest 0.1 mm. India.

Age range - Upper Pliocene to lower Pleistocene (3.9 SYSTEMATIC PALAEONTOLOGY Ma- ~2.5 Ma).

Order Perissodactyla Owen, 1848 Diagnosis (modified from Qiu et al.,1987) - A large- Suborder Hippomorpha Wood, 1937 sized hipparionine species. Female with small canine, Family Equidae Gray, 1821 labial wall of lower incisor grooved, infolding band Tribe Hipparionini Quinn, 1955 crenulated; lower cheek teeth similar to P. houfenense (Teilhard de Chardin & Young, 1931), but more Genus Plesiohipparion Qiu, Huang & Guo, 1987 specialized: ectoflexid wider and shallower than in Type species Hipparion houfenense Teilhard de Chardin the latter, its lingual end expanded considerably, but & Young, 1931 labially strongly constricted by especially developed pli caballinid, which is bi- or trifurcate in moderate stage of Plesiohipparion huangheense (Qiu, Huang & Guo, 1987) wear; metaconid-metastylid dimension very long, with (Fig. 2a-e) extremely wide linguaflexid; entoconid of m3 long, rod- like. Qiu et al. (1987) erected the subgenus Hipparion Lectotype - IVPP V 3104, a left mandible with p2-m3 (Plesiohipparion) for hipparionine horses with weak to (Jen, 1965, pl. 1, fig. 1), stored in the Institute of Vertebrate no preorbital fossa, complicated plications, elongated

Fig. 2 - Comparison of the new specimen of Plesiohipparion huangheense with Chinese and Turkish specimens. a) Line drawing of NHMUK PV OR 15790 with morphological features labeled. b) NHMUK PV OR 15790 occlusal view. c) THP10097 occlusal view. d) HU9102 occlusal view modified from Bernor & Lipscomb (1991). e) NHMUK PV OR 15790 labial view. 128 Bollettino della Società Paleontologica Italiana, 57 (2), 2018

Specimen Tooth M1 M2 M3 M4 M5 M6 M7 M8 M9 M10

NHMUK PV OR 15790 p4 24.37 14.77 8.80 13.45 17.05 13.23 14.23

m1 22.40 13.76

THP10097 p4 25.00 14.60 13.00

m1 22.70 13.80 12.30

HU9102 p4 26.80 22.70 13.60 9.40 13.50 12.90 11.80 11.60 50.40

m1 24.60 13.30 7.80 9.30 9.50 9.40 9.70 45.70

Tab. 1 - Mandibular dental measurements (in mm) of Plesiohipparion huangheense and P. aff.P. huangheense specimens from India, China, and Turkey. p4 = fourth premolar; m1 = first molar; M1 = length at occlusal level; M2 = length 10 mm above the base of the tooth; M3 = length of metaconid-metastylid; M4 = length of the prefossette; M5 = length of the postfossette; M6 = width across plane of ectoflexid/linguaflexid; M7 = width 10 mm above the base of the tooth; M8 = width across plane of metaconid and enamel band labial to protoconid; M9 = width across plane of metastylid and enamel band labial to hypoconid; M10 = crown height as measured from base to occlusal level on mesial face of the tooth. protocones and the houfenoid type of metaconid- Of particular importance are the metaconid-metastylid, metastylid. We follow Bernor & Lipscomb (1991), who linguaflexid and pre- and postflexid morphologies (Fig. subsequently raised Hipparion (Plesiohipparion) to the 2d). As in the Indian specimen, the Gülyazi specimen genus rank Plesiohipparion. lacks protostylids and the m1 has a deeper extending ectoflexid (Fig. 2b, d). All three specimens have similar Hypodigm for N.W. Indian specimen - NHMUK PV morphological dimensions as well (Tab. 1). In the most OR 15790, a mandibular fragment with p4-m1 (Fig. 2b, salient and diagnostic features the Indian, Chinese e; Tab. 1). and Gülyazi specimens are all best referred to the highly derived taxon P. huangheense. Plesiohipparion Locality - Siwalik Hills between the rivers Sutlej and huangheense (and thus the new specimen) differs in Yamuna, N.W. India. dental characters from other species of Plesiohipparion. Plesiohipparion zandaense (Li & Li, 1990) has triangular Age - Upper Pliocene (3.6-2.58 Ma). metaconids and metastylids, but the latter are not as labially elongated as those of P. huangheense (Li & Description - The p4 is elongate and has a lingually Li, 1990). Moreover, the ectoflexid on the m1 of P. pointed metaconid and metastylid with an accompanying zandaense, unlike that in NHMUK PV OR 15790, inserts deep and very broad-U shaped linguaflexid (Fig. 2b). The into the isthmus sometimes touching the labial extent of preflexid has a prominent labially directed mesial pli, the linguaflexid (Li & Li, 1990). The shallow ectoflexid simple enamel margins, and is labio-lingually compressed is an advanced feature in Plesiohipparion (Qiu et al., (Fig. 2b). The postflexid, more elongate than preflexid, 1987; Pang, 2011). Plesiohipparion houfenense has more has a single mesiolabial pli, otherwise has simple enamel strongly triangular metaconids and metastylids than P. margins, and is also labio-lingually compressed (Fig. zandaense but less elongated labially than that of the 2b). The hypoconid, is mesio-distally compressed and Indian specimen; the ectoflexid on m1 is also deeper (Qiu labio-lingually oblong in shape (Fig. 2b). Protoconid, et al., 1987; Bernor et al., 2015; Bernor & Sun, 2015). and hypoconid, enamel bands are flat-walled, and the Plesiohipparion shanxiense Bernor, Sun & Chen, 2015 ectoflexid is shallow with a labially directed single, broad has a dental morphology more similar to P. houfenense pli (Fig. 2b). There is no apparent protostylid on the mesio- than P. huangheense (Bernor et al., 2015). labial margin. The m1 is similar in morphology to the p4 differing only in the hypoconid being more rounded and the ectoflexid projecting more deeply lingually, but not DISCUSSION separating the metaconid-metastylid (Fig. 2b). The genus Plesiohipparion first appeared in the late Comparisons - NHMUK PV OR 15790 compares Miocene of Central Asia. Early representatives include P. closely with a complete mandible, THP10097 from the cf. longipes (Gromova, 1952) from Akkaşdaği, Turkey, Yushe Basin, China (Fig. 2c) with characteristic lingually ca. 7.1 Ma (Koufos & Vlachou, 2005), and P. longipes sharply pointed metaconid and metastylid and deep, very (Gromova, 1952) from Pavlodar in Kazakstan correlative broad U-shaped linguaflexid. Pre- and postflexids are as to MN 13 (Wang et al., 2013a) (Fig. 3). This lineage in the Indian specimen (Fig. 2b-c). Hypoconid is rounded occurs in the early Pliocene Çalta member of the Sinap and ectoflexid is short and lingually expanded as in the Formation in Turkey, ca. 4.0 Ma (Bernor & Sen, 2017) Indian specimen’s m1 (Fig. 2b-c). The only difference here (Fig. 3). In East Asia, Plesiohipparion zandaense from the is that there is a faintly developed, elongate, compressed, Zanda Basin on the Tibetan Plateau is the earliest form, distolabially directed protostylid on the mesiolabial border ranging from 5.95-5.36 Ma (Wang et al., 2013b) (Fig. (Fig. 2c). The Gülyazi specimen, HU9102 shares the 3). Another species, P. houfenense is first found in the same characteristics as the Indian and Chinese specimens. latest Miocene to earliest Pliocene Khunuk Formation in A.M. Jukar et alii - Pliocene Plesiohipparion from India 129

Fig. 3 - Geographic distribution of Plesiohipparion. Black horse silhouettes represent P. huangheense. The two dispersal hypotheses for P. huangheense are shown with black arrows.

Kholobolchi Nor, Mongolia (Flynn & Bernor, 1987; Wang Falconer in Murchison, 1868 dispersed westward into the et al., 2013a) (Fig. 3). By the mid-Pliocene, P. houfenense Levant and parts of Europe (Pilgrim, 1941; Martínez- is found in the Nanzhuanggou member of the Gaozhuang Navarro et al., 2011), while Leptobos Rütimeyer, 1877 Formation (4.9-3.6 Ma) of the Yushe Basin (Qiu et al., arrived in South Asia from the west during the latest 2013), and in various localities in Northern Mongolia, Pliocene, and then dispersed to Northern China by the and the Transbaikal region (Erbajeva & Alexeeva, 2013) early Pleistocene (Rook & Martínez-Navarro, 2010; Mead (Fig. 3). Plesiohipparion huangheense first occurs at 3.9 et al., 2014). Similar connections between India and South Ma in Inner Mongolia (Pang, 2011) (Fig. 3). In the late China have existed since the late Miocene. For example, Pliocene (3.6-2.6 Ma), Plesiohipparion huangheense and Sivalhippus theobaldi has been reported from late Miocene P. houfenense are found in various localities in Northern beds in Lufeng, South China and from the Dhok Pathan China (Jen, 1965; Wang, 1982; Qiu et al., 1987; Cai et Formation in Pakistan (Sun, 2013; Wolf et al., 2013). al., 2013), and as reported in this study, P. huangheense is South Asian taxa such as Stegolophodon stegodontoides also found during this time period in the Siwalik Group of (Pilgrim, 1913) and Enhydriodon Falconer in Murchison, the Indian Subcontinent (Fig. 3). By the early Pleistocene, 1868 occur in the late Pliocene Shagou Formation in Plesiohipparion aff. P. huangheense is found in Gülyazi, Southern China (Qian & Zhou, 1993). Similarities are Turkey (Bernor & Lipscomb, 1991), and a very large also seen in small mammals in the late Neogene (Flynn species, P. shanxiense, is found in Northern China (Bernor & Wessels, 2013). However, connections between North et al., 2015) (Fig. 3). The youngest European member and South China are scarce (Flynn & Wessels, 2013). This of this genus, P. rocinantis (Hernández-Pacheco, 1921) lack of faunal similarity between North and South China is known from La Puebla de Almoradie, Spain (early suggests substantial Palaearctic-Oriental provincialism Pliocene) (Forsten, 1978), Kvabebi, Georgia (~3.07 Ma) in the Pliocene (Wang et al., 2013b), thus, making it less (Agustí et al., 2009), and persists into the early Pleistocene likely that P. huangheense dispersed from North China in Villarroya, Spain (2.14-2.12 Ma) (Pueyo et al., 2016) via a southern route. (Fig. 3). The presence of P. huangheense in the late A northern route for Plesiohipparion huangheense Pliocene of India provides us with an intermediate step is supported by known Pliocene mammalian dispersals in the dispersal of this species from Northern China to across North-Central Eurasia and between Southern and Turkey. Central Asia. The canid Eucyon Tedford & Qiu, 1996 Two dispersal hypotheses are plausible from Northern dispersed from Northern China to Eastern Europe via China: 1) through South China to India south of the Central Asia (Sotnikova & Rook, 2010) while Mammuthus Himalayas, and then west to Turkey; and 2) westward rumanus (Stefanescu, 1924) is found in Britain, Central north of the Tibetan Plateau through Central Asia to Europe and the Yushe Basin in China in the late Pliocene Turkey and southeastward through Afghanistan to India (Markov, 2012). The South Asian alcelaphine Damalops (Fig. 3). Dispersal corridors between Europe, West palaeindicus (Falconer & Walker, 1859) has also Asia, and the Indian Subcontinent have existed since the been reported from the early Pleistocene of Tajikistan Pliocene. Elephas Linnaeus, 1758 immigrated into South (Dimitrieva, 1977). These connections indicate the Asia from the west, and an interchange of bovids has presence of a northern biogeographic corridor between been documented between East Africa and South Asia South Asia, China, Central Asia, West Asia, and Europe. (Shoshani, 1998; Bibi, 2011). The Indian genus Hemibos Late Neogene higher latitude aridification resulted in the 130 Bollettino della Società Paleontologica Italiana, 57 (2), 2018 spread of grasslands in these regions (Bocherens & Sen, expansion of C4 plants: Evidence from lateral variation in stable 1998; Behrensmeyer et al., 2007; Strömberg et al., 2007; isotopes in paleosols of the Siwalik Group, northern Pakistan. Passey et al., 2009), and Plesiohipparion being an open Geological Society of America Bulletin, 119: 1486-1505. habitat specialist (Deng et al., 2012) expanded its range Bernor R.L., Armour-Chelu M., Kaiser T.M. & Scott R.S. (2003a). An evaluation of the late MN 9 (Late Miocene, Vallesian Age), into these environments. Hipparion assemblage from Rudabánya (Hungary): Systematic background, functional anatomy and paleoecology. Coloquios de Paleontología, Volumen Extraordinario, 1: 35-45. CONCLUSION Bernor R.L., Ataabadi M.M., Meshida K. & Wolf D. (2016). The Maragheh hipparions, late Miocene of Azarbaijan, Iran. The presence of Plesiohipparion huangheense in India Palaeobiodiversity and Palaeoenvironments, 96: 453-488. represents a previously unrecognized Pliocene dispersal Bernor R.L., Kaiser T.M., Nelson S.V. & Rook R. (2011). of a Chinese hipparionine lineage into South Asia. As Systematics and paleobiology of Hippotherium malpassii n. such, this occurrence helps clarify the record of Indian sp. (Equidae, Mammalia) from the latest Miocene of Baccinello V3 (Tuscany, Italy). Bollettino della Società Paleontologica Subcontinent hipparion lineages in the Pliocene. The age Italiana, 50: 175-208. of the Indian P. huangheense is intermediate between Bernor R.L., Koufos G.D., Woodburne M.O. & Fortelius M. (1996). the oldest Chinese occurrence (earlier Pliocene) and The evolutionary history and biochronology of European and Turkish occurrence (early Pleistocene) suggesting that Southwest Asian late Miocene and Pliocene Hipparionine the dispersal of P. huangheense from China to India and horses. In Bernor R.L., Fahlbusch V. & Mittman H.W. (eds), Turkey likely occurred in the late Pliocene. Given the The Evolution of Western Eurasian Neogene Mammal Faunas. available evidence, the most parsimonious dispersal route Columbia University Press, New York: 449-469. for P. huangheense is from north of the Tibetan plateau, Bernor R.L., Kovar J., Lipscomb D., Rögl F. & Tobien H. (1988). with the occurrence in India representing a southeastern Systematic, stratigraphic and paleoenvironmental contexts of first appearingHipparion in the Vienna Basin, Austria. Journal range expansion from Central Asia. The presence of of Vertebrate Paleontology, 8: 427-452. forested environments in South China during the Pliocene Bernor R.L. & Lipscomb D. (1991). The systematic position of (Jacques et al., 2011) may have prevented an interchange “Plesiohipparion” aff. huangheense (Equidae, Hipparionini) of open habitat species between North and South China, from Gülyazi, Turkey. Mitteilung der Bayerischen thus making a southerly dispersal less likely. Further Staatssammlung für Paläontologie und historische Geologie, sampling of South China Pliocene mammal faunas is 31: 107-123. needed to better resolve this outstanding issue. Bernor R.L., Mittmann H.-W., Kretzoi M. & Tobien H. (1993). A preliminary systematic assessment of the Rudabánya hipparions. Mitteilungen der Bayerischen Staatssammlung fur ACKNOWLEDGEMENTS Paläontologie und historische Geologie, 33: 1-20. Bernor R.L., Scott R.S., Fortelius M., Kappelman J. & Sen S. We would like to thank P. Brewer, S. Pappa, and E.L. Bernard (2003b). Systematics and evolution of the Late Miocene for access to the fossil mammal collection at the Natural History hipparions from Sinap, Turkey. In Fortelius M., Kappelman J., Museum, London, and Professors Qiu and Deng for access to Sen S. & Bernor R.L. (eds), The Geology and Paleontology of Chinese hipparionine specimens housed at the Tianjin Museum the Miocene Sinap Formation, Turkey. Columbia University of Natural History, Tianjin, China. 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