Stephanorhinus Hundsheimensis
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Quaternary International 302 (2013) 169e183 Contents lists available at SciVerse ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint Stephanorhinus hundsheimensis (Rhinocerontidae, Mammalia) teeth from the early Middle Pleistocene of Isernia La Pineta (Molise, Italy) and comparison with coeval British material Manuel Ballatore a, Marzia Breda b,* a Department of Physics and Earth Sciences, University of Ferrara, Via Saragat, 1, Ferrara 44122, Italy b Department of Humanistic Studies, University of Ferrara, Corso Ercole I D’Este, 32, Ferrara 44100, Italy article info abstract Article history: The present work examines the abundant dental remains from the renowned anthropic site of Isernia La Available online 9 February 2013 Pineta (Molise, Italy), early Middle Pleistocene (Middle Galerian). The rhinoceros, Stephanorhinus hundsheimensis, is the most represented species after Bison, and is represented mainly by skull and dental remains and by strongly fractured long bones (suggesting exploitation of the carcasses by the hominine). The high sample size of the dental remains allowed a detailed analysis of the dental mor- phology. The frequency analysis of the morphological characters shows a high degree of regional var- iation within the species with the Isernia population significantly widening the morphological variability of S. hundsheimensis (thus limiting the diagnostic power of several characters). In particular, comparing S. hundsheimensis from Isernia with coeval British populations, some specimens could be safely assigned to S. hundsheimensis that do look strongly anomalous within the British sample but find a match in the wider morphological range of the Isernia specimens. From a biometrical point of view, the Isernia population attains slightly smaller sizes than the coeval British specimens, suggesting a latitudinal size increase gradient. Ó 2013 Elsevier Ltd and INQUA. All rights reserved. 1. Introduction Four Stephanorhinus species are recorded from the European Pleistocene: Stephanorhinus etruscus (Middle and Late Villafranchian, A great variety of rhinoceros species is recorded from the Eu- Early Pleistocene), Stephanorhinus hundsheimensis (Late Villa- ropean Pleistocene. Rhinocerontidae are among the most typical franchian and Galerian, late EarlyeMiddle Pleistocene), Stephano- elements of the Pleistocene mammal faunas and, thanks to their rhinus hemitoechus (Middle Galerian and Aurelian, MiddleeLate wide geographical distribution and number of forms and to their Pleistocene) and Stephanorhinus kirchbergensis (Late Galerian and good preservation rate, are useful biochronological markers. Re- Aurelian, late MiddleeLate Pleistocene). These species are morpho- mains of this taxon are known from the XVII century and were first logically very similar to each other and, due to the scarcity of remains referred to the genus Rhinoceros (at present represented by two in the different sites, the correct specific attribution is sometimes Asian species). During the past century, the European fossils rhi- difficult. In order to find diagnostic characters distinctive among the noceroses were located in the genus Dicerorhinus (at present rep- different species, researchers concentrate on dental material resented by D. sumatrensis), along with the well known extinct (Guérin, 1980; Fortelius et al., 1993; Lacombat, 2005, 2006a; van der Asian genus Coelodonta. Nowadays, the species from the European Made, 2010) which is generally more frequent and best preserved Pleistocene are referred to the genus Stephanorhinus (Groves, 1983) than the cranial or postcranial skeletal elements. This paper reports in which Fortelius et al. (1993) include Pliocene species. However, a detailed analysis of the rhinoceros dental material from Isernia La the name Dicerorhinus is still used by some authors (e.g. Guérin, Pineta (Molise, Italy), which has been attributed to S. hundsheimensis 2004). by Sala (1983) and Sala and Fortelius (1993). 1.1. Stephanorhinus hundsheimensis (Toula, 1902) * Corresponding author. S. hundsheimensis is a slender and medium sized rhinoceros, E-mail addresses: [email protected], [email protected] (M. Breda). with a partially ossified nasal septum. The dentition is reduced to 1040-6182/$ e see front matter Ó 2013 Elsevier Ltd and INQUA. All rights reserved. http://dx.doi.org/10.1016/j.quaint.2013.02.002 170 M. Ballatore, M. Breda / Quaternary International 302 (2013) 169e183 the jugal teeth, with the lack of first premolar. The teeth of The palaeoenvironment reconstruction supported by pollen S. hundsheimensis are low-crowned and very similar, in shape and analysis of the sediment from the archaeosurfaces, indicates proportions, to those of its possible parent species S. etruscus and, a steppe-grassland environment, with dominant Graminaceae, but as in the latter, probably adapted to a browsing diet. S. hemitoechus also tree species related to wet and marshy environment such as is distinguishable because of its higher hypsodonty (especially of Alnus, Salix and Populus (Accorsi et al., 1996). Presence of extended the molars), while S. kirchbergensis because of its larger size and grassland and restricted woodland, particularly in the valley bot- “molten” shape of the molars (Fortelius et al., 1993). tom and related to the presence of water, is in accordance with the S. hundsheimensis is recorded in the whole of Europe, in the late variety of large mammals: bison, rhinoceros and elephant are Early and Middle Pleistocene (Fortelius et al., 1993; Mazza et al., typical inhabitants of grassland; deer and wild boar of bush; hip- 1993; Lacombat, 2005; Schreiber, 2005; van der Made, 2010). popotamus indicates the presence of abundant water bodies and Lacombat (2006b), Fortelius et al. (1993), and Breda and Marchetti swamp. (2007) recognize two evolutionary stages: a smaller form from the Early Pleistocene (often misidentified with S. etruscus) and a larger 2. Materials and methods one from the early Middle Pleistocene. On the contrary, van der Made (2010) believes that these small forms are actually S. etruscus. In the teeth analysis, a total of 202 specimens have been studied, The brachyodont dentition and the slender, subcursorially some of them consisting in associated teeth, thus getting to a total structured limbs suggest that both S. etruscus and S. hundsheimensis number of 229 studied teeth. The material comes from the Isernia probably inhabited environments with variable forest cover similar La Pineta levels identified as 3a, 3coll and 3s 10-1 (Thun Hohenstein to those in which black rhino lives today, i.e. open scrub woodlands et al., 2009), and is now stored partially in the Museo del Paleolitico, and the margins of small woods (Mazza, 1993). Evidence for a var- in Isernia La Pineta, and partially in the Palaeontology and Prehis- iable forest cover has been suggested by the pollen analysis of the tory Museum “Piero Leonardi” of the University of Ferrara sediment adhering to S. etruscus-hundsheimensis bones from Leffe, (Department of Biology and Evolution). Northern Italy (Ravazzi et al., 2009). The Leffe record documents Most of the dental material is represented by isolated teeth so the occurrence of this rhinoceros in warm-temperate dense mixed the recognition of their place in the tooth row is sometimes diffi- forest to conifer forest, to open xerophytic communities and steppe cult. Identification of P2 and M3 is straightforward but distinction with tree birch and with sparse woodland patches. between P3 and P4 or M1 and M2 is often problematic because of The extinction of S. hundsheimensis is probably due to ecological their close morphology. A size-based distinction is not used in order competition: the more specialized rhinoceroses S. hemitoechus, to avoid data circularity and amplification of the average size dif- a grazer, and S. kirchbergensis, a stricter browser, probably over- ference among dental types. The following morphological dis- came the generalist S. hundsheimensis in both forest and grassland tinction for molars are used: in comparison to M1,M2 has a more habitats leading to its extinction through bilateral competition distally elongated metaloph resulting in a wider lingual valley, and (Kahlke and Kaiser, 2011). in a more trapezoidal shape in occlusal view (distal side shorter than medial one); M1 differs from M2 for the presence of a bulge along the syncline (see Fig. 1 for dental nomenclature). The pre- 1.2. Isernia La Pineta Palaeolithic site molars cannot be identified with certainty. Morphological analysis considered the characters analysed in Discovered in 1978 and now dated to 610,000 Æ 10,000 years previous studies on this taxon by Guérin (1980), Fortelius et al. (Coltorti et al., 2005), the archaeological levels of Isernia yielded an (1993) and Lacombat (2005). Fig. 2 summarizes the characters extremely rich and well-preserved amount of palaeontological re- examined and the different possible states for each. For the median mains and lithic artefacts, evidence of an ancient human settlement fossette (character d) a new state is introduced, here called along the river side. The mammal fauna from Isernia is particularly abundant and well-documented, although made up of isolated and commonly fragmented specimens (Arobba et al., 2004; Thun Hohenstein et al., 2009). Rhinoceroses are well represented by cranial and postcranial elements, with long bones usually frag- mented, but teeth and short bones generally intact. In terms of number of remains, S. hundsheimensis