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Arvicola materials from Mosbaeh 2, including the types of A. mosbachensis housed at the Forschungsinstitut Senckenberg Frankfurt am Main, are described. Six specimens display incipient root development. This population is therefore one of the oldest of the genus Arvicola. This is confirmed by SDQ and tooth length values indicating a primitive evolutionary stage. The age of the population correlates with either Cromer lnterglacial III or IV.The type material of Arvicola cantianus consists of a few fragmentary molars only. This scarce material does not permita clear assessment of the most significant features in middle Pleistocene populations, rootless molars with negative enamel differentiation, and is not clearly distinguishable flora either Mimomys savini of Arvicola terrestris. We therefore propose to restrict the name A. cantianus to the type material. All other middle Pleistocene Arvicola finds should be referred to A. mosbachensis.

Recent water voles (genus Arvicola) display a prominent morphological diversity with a strong ecotypical background but with unclear taxonomic associations. We provide a novel synthetic view on the evolutionary history and the current taxonomic richness in the genus. Our molecular reconstruction, based on a 1143-bp-long sequence of cytochrome b and a 926-bp interphotoreceptor retinoid binding protein (irbp) confirmed the monophyly of four species (amphibius, sapidus, monticola and italicus) recognized thus far, and retrieved a new deeply divergent lineage from West Iran. Genetic divergence of the Iranian lineage (>9.0%) is inside the range of interspecies distances, exceeding the interspecies divergences between the remaining Arvicola species (range, 4.3–8.7%). The oldest name available for the Iranian phylogroup is Arvicola persicus de Filippi, 1865, with the type locality in Soltaniyeh, Iran. The molecular clock suggests the divergence of A. persicus in the Early Pleistocene (2.545 Ma), and the current radiation of the remaining species between 1.535 Ma (Arvicola sapidus) and 0.671 Ma. While A. sapidus possibly evolved from Arvicola jacobaeus, a fossil ancestor to A. persicus is unknown. The aquatic life-style of Mimomys savini, a direct ancestor to some fossil Arvicola, is retained in recent stem species A. sapidus and A. persicus, while a major shift toward fossorial morphotype characterizes the terminal lineages (amphibius, italicus and monticola). We suggest that habitat-dependent morphological plasticity and positive enamel differentiation in Arvicola amphibius widened its ecological niche that might trigger a range expansion across c. 12 million km2, making it one of the largest among arvicolines.

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Please cite this article as: Ulbricht, A., Maul, L.C., Schulz, E.,Can mesowear analysis be applied to small mammals? A pilot-study on leporines and murines, Mammalian Biology (2014), http://dx. Abstract 14In recent years, various methods have been developed to infer from mammal tooth wear 15 patterns the abrasiveness of the food they consumed, which reflects the amount of dust in 16 their habitat and thus the environment they inhabit. One of these methods is mesowear 17 analysis, which is applied particularly to fossils in order to reconstruct palaeoenvironment, 18 but increasingly also to species protection management of recent animals. In numerous 19 studies this method has been applied to the teeth of large herbivorous mammals. Despite 20 the well-known importance of small mammal fossils, which occur in great numbers in 21 countless Cenozoic sites giving a large sample size and provide significant palaeontological 22 data, mesowear analysis has not yet been applied to this group. In the present work, teeth 23 of various hare and mice species (Leporinae and Murinae) are subjected to a mesowear 24 analysis for the first time. We aim to test the applicability of the method in these groups. 25Our results clearly indicate that significant mesowear signals are evident in Leporinae as well 26 as Murinae, reflecting known habitat conditions of the species. Furthermore, problems and 27 limitations of the application of the mesowear methods on small mammal teeth are 28 discussed. 29