Discovery of two crania of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 (Mammalia, Perissodactyla) from the Late Pleistocene of Khakassia, Russia

2025  47  19 geodiversitas Geodiversitas est une revue en flux continu publiée par les Publications scientifiques du Muséum, Paris Geodiversitas is a fast track journal published by the Museum Science Press, Paris Les Publications scientifiques du Muséum publient aussi / The Museum Science Press also publish: Adansonia, Zoosystema, Anthropozoologica, European Journal of Taxonomy, Naturae, Cryptogamie sous-sections Algologie, Bryologie, Mycologie, Comptes Rendus Palevol Diffusion – Publications scientifiques Muséum national d’Histoire naturelle CP 41 – 57 rue Cuvier F-75231 Paris cedex 05 (France) Tél. : 33 (0)1 40 79 48 05 / Fax : 33 (0)1 40 79 38 40 [email protected] / http://sciencepress.mnhn.fr © Publications scientifiques du Muséum national d’Histoire naturelle, Paris, 2025 ISSN (imprimé / print) : 1280-9659/ ISSN (électronique / electronic) : 1638-9395 Directeur De la publication / Publication director : Gilles Bloch, Président du Muséum national d’Histoire naturelle réDacteur en chef / editor-in-chief : Didier Merle réDacteur associé / associate editor: Sylvain Charbonnier assistant De réDaction / assistant editor : Emmanuel Côtez ([email protected]) Mise en page / Page layout : Emmanuel Côtez coMité scientifique / scientific board : Christine Argot (Muséum national d’Histoire naturelle, Paris) Beatrix Azanza (Museo Nacional de Ciencias Naturales, Madrid) Raymond L. Bernor (Howard University, Washington DC) Henning Blom (Uppsala University) Gaël Clément (Muséum national d’Histoire naturelle, Paris) Ted Daeschler (Academy of Natural Sciences, Philadelphie) Cédric Del Rio (Muséum national d’Histoire naturelle) Gregory D. Edgecombe (The Natural History Museum, Londres) Ursula Göhlich (Natural History Museum Vienna) Jin Meng (American Museum of Natural History, New York) Brigitte Meyer-Berthaud (CIRAD, Montpellier) Zhu Min (Chinese Academy of Sciences, Pékin) Isabelle Rouget (Muséum national d’Histoire naturelle, Paris) Sevket Sen (Muséum national d’Histoire naturelle, Paris, retraité) Stanislav Štamberg (Museum of Eastern Bohemia, Hradec Králové) Paul Taylor (The Natural History Museum, Londres, retraité) couverture / cover : Réalisée à partir des Figures de l’article/Made from the Figures of the article. Geodiversitas est indexé dans / Geodiversitas is indexed in: – Science Citation Index Expanded (SciSearch®) – ISI Alerting Services® – Current Contents® / Physical, Chemical, and Earth Sciences® – Scopus® Geodiversitas est distribué en version électronique par / Geodiversitas is distributed electronically by: – BioOne® (http://www.bioone.org) Les articles ainsi que les nouveautés nomenclaturales publiés dans Geodiversitas sont référencés par / Articles and nomenclatural novelties published in Geodiversitas are referenced by: – ZooBank® (http://zoobank.org) 713 GEODIVERSITAS • 2025 • 47 (19) © Publications scientifiques du Muséum national d’Histoire naturelle, Paris. www.geodiversitas.com MOTS CLÉS Pléistocène supérieur, Mammalia, Perissodactyla, Equus, Sibérie, Khakassie, craniométrie. KEY WORDS Late Pleistocene, Mammalia, Perissodactyla, Equus, Siberia, Khakassia, craniometry. urn:lsid:zoobank.org:pub:AF7BC1E5-64AC-4C66-AB5A-7F8317BD79B7 Eisenmann V. & Vasiliev S. K. 2025. — Discovery of two crania of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 (Mammalia, Perissodactyla) from the Late Pleistocene of Khakassia, Russia. Geodiversitas 47 (19): 713-720. https://doi.org/10.5252/geodiversitas2025v47a19. http://geodiversitas.com/47/19 ABSTRACT Two crania, 40 000 years old, collected inside the Fanatics Cave in Khakassia (Southern Siberia) have improved our knowledge of Equus ovodovi Eisenmann & Vasiliev, 2011 anatomy. Equusovodovi belongs to the subgenus Sussemionus Eisenmann, 2010 all other members of which went extinct during the Middle Pleistocene. By cranial morphology as well as by other anatomical and molecular characters, E. ovodovi differs from all other Equus species and in particular from E.hydruntinus Regàlia, 1907 to which it was initially referred. E.ovodovi has narrower choanae and supra-occipital crest and a longer muzzle. By these features it resembles E.vekuae Eisenmann, 2022 from the Early Pleistocene of Dmanisi, Georgia, another species belonging or closely related to the subgenus Sussemionus. It differs from it, however, by the position of hormion relative to basion and staphylion. RÉSUMÉ Découverte de deux crânes d’Equus (Sussemionus) ovodovi Eisenmann& Vasiliev, 2011 (Mammalia, Perissodactyla) du Pléistocène supérieur de Khakassie, Russie. Deux crânes, vieux de 40 000 ans, provenant de la Grotte des Fanatiques, en Khakassie (Sibérie méridionale, Russie), sont venus améliorer notre connaissance de l’anatomie d’Equus ovodovi Eisenmann& Vasiliev, 2011. Cette espèce appartient au sous-genre Sussemionus Eisenmann, 2010 dont tous les autres membres ont disparu depuis le Pléistocène moyen. Par la morphologie crânienne comme par d’autres caractères anatomiques et moléculaires, E. ovodovi diffère de tous les autres Equus, en particulier d’E.hydruntinus Regàlia, 1907 avec lequel il fut initialement confondu : E.ovodovi présente une protubérance occipitale externe et des choanes plus étroites et un museau plus long. Par ces caractères, E.ovodovi ressemble à E.vekuae Eisenmann, 2022 (Pléistocène inférieur de Dmanisi en Géorgie) – une autre espèce appartenant ou apparentée aux sussemiones – mais en diffère par la position de l’hormion par rapport au basion et au staphylion. Equusvekuae est une autre espèce appartenant ou apparentée aux sussemiones. Véra EISENMANN Centre de recherche en paléontologie — Paris (CR2P), CNRS, MNHN, Sorbonne Université, Département Origines et Évolution, Muséum national d’Histoire naturelle, case postale 38, 57 rue Cuvier, F-75231 Paris cedex 05 (France) [email protected] Sergei K. VASILIEV Institute of Archaeology and Ethnography, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk (Russia) [email protected] Submitted on 29 April 2025 | accepted on 1 July 2025 | published on 4 November 2025 Discovery of two crania of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 (Mammalia, Perissodactyla) from the Late Pleistocene of Khakassia, Russia 714 GEODIVERSITAS • 2025 • 47 (19) Eisenmann V.& Vasiliev S. K. INTRODUCTION Equus ovodovi Eisenmann& Vasiliev, 2011 was a paleontological surprise. DNA analyses of supposed E.hydruntinus Regàlia, 1907 fossils from southern Siberia led instead to the discovery of a new clade of Equus Linnaeus, 1758, with no extant relative, and distinct from E.hydruntinus (Orlando etal. 2009). Reexamination of the teeth and metapodials confirmed that they did not belong to E.hydruntinus, instead its characters pointing to a relationship with members of the subgenus Sussemionus Eisenmann 2010 (Eisenmann& Vasiliev 2011). The species referred to Sussemionus were supposed extinct since the A B C fig. 1. — Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 cranium IAET-1: A, profile; B, dorsal view; C, ventral view. Scale bar: 10 cm. Photos: S. K. Vasiliev. 715 Discovery of two crania of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 from the Late Pleistocene of Russia GEODIVERSITAS • 2025 • 47 (19) Middle Pleistocene, while the studied Siberian fossils belong to a new species, E. (Sussemionus) ovodovi Eisenmann& Vasiliev, 2011 are dated c.40 000 year old. The material included only upper and lower cheek teeth and some limb bones. Two crania recently found in another close locality of Khakassia – the vertical Fanatics trap-Cave – by paleozoologist N.D. Ovodov in 1983 allow us to better understand the anatomy of this species and its differences compared to other species included in the subgenus Sussemionus. The trap-cave is located in the south-east of Western Siberia, in the central part of Khakassia (53°19’N, 90°20’E). The bones of Holocene mammals (mainly hares, rodents, and martens) were collected from the surface layer, while the remains of Pleistocene-aged animals lay below. They include: – Five skeletons of cave hyenas (Crocuta spelaea Goldfuss, 1823) (Vasiliev& Ovodov 2024). – Incomplete skeletons of a wolf (Canis lupus Linnaeus, 1758) and a wolverine (Gulo gulo Linnaeus, 1758), as well as individual bones and skulls from three and two individuals, respectively, A B C fig. 2. — Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 cranium IAET-2: A, ventral view; B, dorsal view; C, profile. Scale bar: 10 cm. Photos: S. K. Vasiliev. 716 GEODIVERSITAS • 2025 • 47 (19) Eisenmann V.& Vasiliev S. K. – Remains of Martes zibellina (Linnaeus, 1758), Putorius eversmanni (Lesson, 1827), Vulpes vulpes (Linnaeus, 1758) and Vulpes corsac (Linnaeus, 1768), – Remains from three individuals of Bison priscus (Bojanus, 1827), including a lower jaws, a skull fragment, and several limb bones. table 1. — Measurements (in mm) of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 crania (Table) and Simpson’s ratio diagrams (Figure). Measures: 2-5, palatal length sensu stricto; 3, vomerine length; 4, postvomerine length; 5, muzzle length; 9, length of choanae; 10, greatest choanal breadth; 13, frontal breadth; 16, breadth of the supra-occipital (lambdoidal) crest; 17, muzzle breadth at the posterior borders of I3; 17bis, least muzzle breadth between the crests; 20, height of the external auditive meatus; 23, anterior ocular line; 25, facial height in front of P2; 28, cranial height; 31, length of the naso-incisival notch; 32, cheek length. Dm53/59.B1gl192 EBK Ba2 C1(B) 384 Dmanisi Fanatics Fanatics Emine Bair Khosar Measure number E. vekuae E. ovodovi 1 E. ovodovi 2 E. hydruntinus Measurements 57.2 16 47.4 46 –52.9 345.1 23 371 330 –320 118.7 3 107.6 118 118 101.5 101.8 4 108 107.2 101.2 106.8 113.6 2-5 125 119.6 108 119.3 103.8 5 121.6 118.7 –88 55.3 17 62 63.8 –57.4 41.5 17bis 42.5 42.2 –40.3 195.9 13 198.4 197 192 184 47.6 10 44 43.4 45.2 49.5 101.5 25 –85.3 –88.8 89.5 28 82.8 91.6 –90 62.5 9 56.8 – – – 14.4 20 12.2 –13.5 – 143.0 31 160 141.5 –132.1 162.3 32 154 173 –170 433.4 1 –459 –409 Log10 E.h.o. 1.757 16 –0.082 –0.095 ––0.034 2.538 23 0.031 –0.019 ––0.033 2.074 3 –0.043 –0.003 –0.003 –0.068 2.008 4 0.026 0.022 –0.003 0.021 2.055 2-5 0.042 0.022 –0.022 0.021 2.016 5 0.069 0.058 ––0.072 1.743 17 0.050 0.062 –0.016 1.618 17bis 0.010 0.007 ––0.013 2.292 13 0.006 0.002 –0.009 –0.027 1.678 10 –0.034 –0.040 –0.022 0.017 2.006 25 ––0.076 ––0.058 1.952 28 –0.034 0.010 –0.002 1.796 9 –0.042 – – – 1.158 20 –0.072 ––0.028 – 2.155 31 0.049 –0.005 ––0.034 2.210 32 –0.023 0.028 –0.020 0.100 0.050 –0.050 –0.100 –0.150 16 23 34 51713102528920 31 3217bis2-5 0.000 E. vekuae E. ovodovi 1E. ovodovi 2E. hydruntinus 717 Discovery of two crania of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 from the Late Pleistocene of Russia GEODIVERSITAS • 2025 • 47 (19) Three radiocarbon dates have been obtained from bone remains of Fanatics Cave. For two individuals of cave hyenas, they were 42 140 ± 330 and 37 350 ± 448 BP, and an exorbitant dating (>50 000 years old) was obtained for a humerus of the Baikal yak Poehagus mutus baicalensis Verestchagin, 1954 (Vasiliev etal. 2020). MATERIAL AND METHODS Each of the E.ovodovi crania disintegrated into several dozen fragments during their extraction but in three places on cranium IAET-1 and in two places on cranium IAET-2, the connecting areas between the occipital and anterior parts of the skull were preserved, which allowed them to be anatomically reliably connected. After a long and minutious reconstruction, it was possible to restore both (Figs 1; 2). They were measured according to the method described by Eisenmann (1986). Their size and proportions (Tables 1; 2) were compared by Simpson's diagrams with E.hemionus onager Boddaert, 1785 as reference to other crania, in particular to the perfectly preserved cranium of E.hydruntinus from Ukraine published by Van Asperen etal. (2012). Dimensions of the upper cheek teeth were compared to another sample of E. ovodovi teeth found in the Logovo hyenae Cave, Altai (Appendix 1). AbbreviAtions I incisor; M molar; MIS Marine Isotopic Stage; P premolar; x mean; min minimum; max maximum; s standard deviation; v coefficient of variation. RESULTS As expected, E.ovodovi crania do not resemble E.hydruntinus nor any extant species (Eisenmann 2022: figs 28, 42) though such narrow supra-occipital crests occur in extant and fossil horses (Eisenmann 2022: figs 58, 62). From E.hydruntinus they differ mainly (Table 1) by the smaller breadth of their supra-occipital crest (measure 16), their longer muzzle (measure 5) and their relatively narrow choanae (measure 10). Surprisingly, they are rather similar to the Early Pleistocene E.vekuae Eisenmann, 2022 from Dmanisi (Eisenmann 2022: 57) apart from their relatively shorter post-vomerine length (measure 4) and their relatively deeper naso-incisival notch (measure 32). The teeth are similar to that of the E.ovodovi type and other specimens from Proskuriakova, and differ from E.hydruntinus by longer protocones (Eisenmann & Vasiliev 2011). DISCUSSION The fossils from the Fanatics Cave have the same localization (Khakassia) as those of Proskuriakova holotype and are about the same age (c. 40 000 years). But the range of E.ovodovi was larger both in space and time. Several fossils have been found in the Middle Pleistocene (MIS-7-8) slightly north of Novosibirsk and in the Late Pleistocene (MIS-3 and MIS-5). The range of E.ovodovi included not only the south of Western and Central Siberia (Plasteeva etal. 2019), but extended up to northeastern China (Yuan etal. 2019). It was in this region that during the excavations of several monuments of the Shan culture, the most recent (3.5-4 thousand years ago) remains of E.ovodovi were found. In addition to the morphology of the remains themselves, this was also confirmed by the results of biomolecular studies (Cai etal. 2022). In the Old World, the subgenus Sussemionus is documented by robust species at least from the middle Olyorian (c.600 000 year) in Northeastern Siberia by E.verae, and slightly later by E.coliemensis Lazarev, 1980. Slender “pseudohydruntines” species originally comprised in the subgenus table 2 . — Measurements in mm of upper cheek teeth of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 from Fanatics Cave, Khakassiaw (Institute of Archaeology and Ethnography, Novosibirsk). Measure description Measure number IAET-1 IAET-2 Basilar length 1 459 452 Palatal length 2 235 231 Palatal length sensu stricto 2-5 119 106.7 Vomerine length 3 118 118 Postvomerine length 4 107.2 101.2 Muzzle length 5 116 – Diastema length 6 92 – Length of premalers (P2-P43) 7 88.3 85.1 Length of molars (M1-M3) 7 bis 72.5 72 Length of cheek teeth (P2-M3) 8 159 155 Length of choanae 9 – – Greatest choanal breadth 10 43.4 45.2 Frontal breadth 13 197 192 Bizygomatic breadth 14 168.2 – Cranial breadth 15 109 – Breadth of the supra-occipital (lambdoidal) crest 16 46 – Muzzle breadth at the posterior borders of I3 17 63.8 – Least muzzle breadth between the crests 17bis 42.2 – Vertex length 18 508 – Infra-orbital height 19 9 9.2 Height of the external auditive meatus 20 –13.5 Antero-posterior diameter of the orbit 21 58.5 63 Dorso-ventral diameter of the orbit 22 55.5 – Anterior ocular line 23 330 – Posterior ocular line 24 175.3 – Facial height in front of P2 25 85.3 – Facial height between P4 and M1 26 132.8 – Cranial height 28 91.6 89.5 Breadth of the occipital condyles 29 81 73 Breadth of the foramen magnum 30 34 32 Length of the naso-incisival notch 31 141.5 – Cheek length 32 173 – 718 GEODIVERSITAS • 2025 • 47 (19) Eisenmann V.& Vasiliev S. K. may perhaps be a distinct group (Eisenmann 2022) to which belongs the Early Pleistocene E.vekuae. Granted that resemblances between E.vekuae and E.ovodovi are limited to a few cranial proportions, it seems yet worth to mention them. Acknowledgements We are deeply thankful to Sevket Sen for correcting the numerous misprints and errors in our article and sincerely thank the reviewers, Nicolas Boulbes (Université Perpignan Via Domitia) and an anonymous referee, for taking time to read and improve our work. REFERENCES CAi D., Zhu s., GonG M., ZhAnG n., Wen J., [...] & JiAnG Y. 2022.— Radiocarbon and genomic evidence for the survival of Equus Sussemionus until the late Holocene. eLife 2022; 11:e73346.: https://doi.org/10.7554/eLife.73346 eisenMAnn v. 1986. — Comparative osteology of modern and fossil Horses, Halfasses and Asses, in MeAsoW r. h. & uerpMAnn H. P. (eds), Equids in the Ancient World. Beihefte zum Tübinger Atlas des Vorderen Orients, Reihe A: Wiesbaden: 67–116. e isenMAnn v. 2010. — Sussemionus, a new subgenus of Equus (Perissodactyla, Mammalia). Comptes Rendus Biologies 333: 235240. https://doi.org/10.1016/j.crvi.2009.12.013 eisenMAnn v. 2022. — Old World fossil Equus (Perissodactyla, Mammalia), extant wild relatives and incertae sedis forms. Quaternary 5 (3), 38. https://doi.org/10.3390/quat5030038 eisenMAnn v. & vAsiliev s. 2011. — Unexpected finding of a new Equus species (Mammalia, Perissodactyla) belonging to a supposedly extinct subgenus in Late Pleistocene deposits of Khakassia (southwestern Siberia). Geodiversitas 33 (3): 519-530. https://doi.org/10.5252/g2011n3a5. https://sciencepress.mnhn.fr/en/periodiques/geodiversitas/33/3/ decouverte-inattendue-dans-le-pleistocene-superieur-de-khakassiesud-ouest-siberien-d-une-nouvelle-espece-d-equus-mammaliaperissodactyla-appartenant-un-sous-genre-suppose-eteint orlAnDo l., MetCAlf J. l., AlberDi M.-t., telles-Antunes M., bonJeAn D., [...] & Cooper A. 2009. — Revising the recent evolutionary history of equids using ancient DNA. Proceedings of the National Academy of Sciences 106 (51): 21754-21759. https:// doi.org/10.1073/pnas.0903672106 plAsteevA n. A., vAsiliev s. K., KleMentiev A. M. & Kosintsev p. A. 2019. — Morphological differentiation of Equids (Equus ovodovi, Equus hemionus) and their distribution ranges in Western Siberia in the Late Pleistocene. Zoological Journal 98 (10): 11561167. (In Russian). https://doi.org/10.1134/S0044513419100106 v An A speren e. n., s tefAniAK K., p rosKurnYAK i. & r iDush b. 2012. — Equids from Emine-Bair-Khosar Cave (Crimea, Ukraine): co-occurrence of the stenonid Equus hydruntinus and the caballoid E.ferus latipes based on skull and postcranial remains. Palaeontologia Electronica 15 (1), 5A: 1-28 [retrieved from https://www.palaeo-electronica.org/content/2012-issue1-articles/124-equidsfrom-emine-bair-khosar]. vAsiliev s. K. & ovoDov n. D. 2024. — Remains of cave hyenas Crocuta spelaea (Hyaenidae) from Late Pleistocene cave and alluvial localities in southern Western Siberia. Proceedings of the Zoological Institute of the RAS 328 (3): 454-485 (in Russian). https://doi.org/10.31610/trudyzin/2024.328.3.454050.519-530 vAsiliev s. K., pArKhoMChuK e. v., sereDnYov M. A., Milutin K. i., rAstiGeev s. A. & pArKhoMChuK v. v. 2020. — Late Pleistocene megafauna of the South of Western and Central Siberia: new data on radiocarbon dating and new finds from alluvial localities in 2020. Problems of Archeology, Ethnography, Anthropology of Siberia and Neighboring Territories 26: 43-50 (in Russian). https://doi.org/10.1746/2658-6193.2020.26.043-050 YuAn J.-X., hou X.-D., bArloW A., preiCK M., tAron u. h., Alberti f., bAsler n., DenG t., lAi X.-l., hofreiter M. & s henG G.-l. 2019. — Molecular identification of late and terminal Pleistocene Equus ovodovi from northeastern China. PLoS ONE 14 (5): e0216883. https://doi.org/10.1371/journal. pone.0216883 Submitted on 29 April 2025; accepted on 1 July 2025; published on 4 November 2025. 719 Discovery of two crania of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011 from the Late Pleistocene of Russia GEODIVERSITAS • 2025 • 47 (19) E. ovodovi, Fanatic Cave IAET-1 IAET-2 sin dex sin dex P2/-M3/ alveloar length 160 159.7 157.5 157 P2/-M3/ occlusal length 159.2 159 154.6 155 P2/ occlusal length 35 36 34.3 33.5 protocone length 8.2 7.8 7.1 7.1 occlusal breadth 23.3 24.2 23.7 23.1 crown height 33 45 46 protocone index 23.43 21.67 20.7 21.19 P3/ occlusal length 27 26.8 26.2 26.9 protocone length 10.4 10.5 8.7 9 occlusal breadth 25.1 25.8 24.5 24.5 crown height 34 53 protocone index 38.52 39.18 33.21 33.46 P4/ occlusal length 26 26 26 25.3 protocone length 11.3 11.4 9.9 9.2 occlusal breadth 25.9 26.5 25.1 25.4 crown height protocone index 43.46 43.85 38.08 36.36 M1/ occlusal length 23 24 22.8 22.5 protocone length 12.1 11.9 8.6 8.2 occlusal breadth 25.6 25.5 25 24.8 crown height 45 54 protocone index 52.61 49.58 37.72 36.44 M2/ occlusal length 23.7 23.3 23 23.6 protocone length 13 12.6 10 9.8 occlusal breadth 25.5 25.4 24.6 24.7 crown height 46 56 protocone index 54.85 54.1 43.48 41.53 M3/ occlusal length 27 26.7 26.6 26 protocone length 12 12.3 10.8 10.4 occlusal breadth 23 23.7 22.2 22.2 crown height 49 60 protocone index 44.44 46.07 40.6 40 Equus ovodovi P2, Fanatic Cave n x min max s v occlusal length 4 34.7 33.5 36 1.06 3.05 protocone length 4 7.55 7.1 8.2 0.54 7.15 occlusal breadth 4 23.58 23.1 24.2 0.49 2.08 crown height 3 41.33 33 46 7.23 17.49 protocone index 4 21.75 20.7 23.43 1.19 5.47 Equus ovodovi M1-M2, Fanatic Cave n x min max s v occlusal length 8 23.24 22.5 24 0.5 2.15 protocone length 8 10.78 8.2 13 1.86 17.25 occlusal breadth 8 25.14 24.6 25.6 0.41 1.63 crown height 4 50.25 45 56 5.56 11.06 protocone index 8 46.29 36.44 54.85 7.42 16.03 Equus ovodovi M3, Fanatic Cave n x min max s v occlusal length 4 26.58 26 27 0.42 1.58 protocone length 4 11.38 10.4 12.3 0.92 8.08 occlusal breadth 4 22.78 22.2 23.7 0.72 3.16 crown height 2 54.5 49 60 7.78 14.28 protocone index 4 42.78 40 46.07 2.95 6.90 Equus ovodovi P2, Logovo hyaeny Cave, mid-wear n x min max s v occlusal length 20 36.14 32.5 40.8 2.23 0.5 protocone length 28 7.84 6.3 9.8 1.04 0.2 occlusal breadth 27 24.52 20.4 27.7 1.36 0.26 crown height 28 35.61 26 48 6.05 1.14 protocone index 20 21.68 15.9 26.6 2.81 0.63 Equus ovodovi M1-M2, Logovo hyaeny Cave, mid-wear n x min max s v occlusal length 112 24.3 21.5 26.7 1.14 0.11 protocone length 120 11.19 8.5 13.5 1.06 0.1 occlusal breadth 115 26.36 23.6 29.7 1.21 0.11 crown height 120 45.07 29 62 8.91 0.81 protocone index 111 46.16 33.9 57.5 4.3 0.41 Equus ovodovi M3, Logovo hyaeny Cave, mid-wear n x min max s v occlusal length 52 27.68 24.5 32 1.51 0.21 protocone length 56 12.8 10.4 15 1.17 0.16 occlusal breadth 55 23.47 21.2 25.9 0.97 0.13 crown height 58 45.02 28 63 9.53 1.25 protocone index 52 46.55 39 59.2 4.71 0.65 appenDix 1. — Measures in mm of upper cheek teeth of Equus (Sussemionus) ovodovi Eisenmann & Vasiliev, 2011. Equus ovodovi P3-P4, Fanatic Cave n x min max s v occlusal length 8 26.28 25.3 27 0.58 2.21 protocone length 8 10.05 8.7 11.4 1.03 10.25 occlusal breadth 8 25.35 24.5 26.5 0.7 2.76 crown height 2 43.5 34 53 13.44 30.90 protocone index 8 38.27 33.21 43.85 3.99 10.43 Equus ovodovi P3-P4, Logovo hyaeny Cave, mid-wear n x min max s v occlusal length 73 27.3 25 29.6 1 0.12 protocone length 74 10.71 8 13.3 1.02 0.12 occlusal breadth 67 26.74 24 29.5 1.33 0.16 crown height 74 45.08 26 61 7.99 0.93 protocone index 72 39.49 30.5 51.2 3.56 0.42