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Simplomys, a dormouse with a simple dental morphology compared to other glirids, shows a continuous evolution in Spain during the end of the Ramblian and up to the middle Aragonian, the stratigraphic frame considered in this work. In contrast, the record of the genus in Central Europe is reduced to a few localities spanning from the early to the middle Miocene. We review the record from the Burdigalian to Langhian equivalent to the deposition of the uppermost Upper Marine Molasse (OMM) to the lower part of the Upper Freshwater Molasse (OSM) and conclude the occurrence of three distinct species. The youngest species, Simplomys simplicidens, is recognised in Schönenberg (Germany, MN5) and Courrendlin-Solé (Switzerland; MN4). Material from a fissure filling near Glovelier (Switzerland, MN4) supplied the new species, Simplomys hugi, whereas the localities Petersbuch 2 and Erkersthofen 2 (both fissure fillings from Germany, MN4) contain species closely related to it. Finally, and pending further advances in the taxonomy of the Iberian Simplomys, the oldest population from the fissure filling of Schnaitheim (Germany; MN3) remains in open nomenclature (Simplomys sp.). The genus Simplomys has not been recorded eastwards from the Swabian and Franconian Jura Plateaus from Germany and its youngest occurrence in Schönenberg is correlated to the South German local scale OSM C+D, at around 15.5 Ma. [ABSTRACT FROM AUTHOR]

The Oligocene fossil deposits from Valley of Lakes in Central Mongolia have provided a wealth of rodent fossils. Among these, cricetids are a very important part. To date, only the Miocene genera have been described in detail. Here, we focus on the Oligocene genus Eucricetodon from this region. Eucricetodontinae are the most abundant fossils in the Oligocene Valley of Lakes faunas. The present study consists of the description of five species of cricetid rodents from 43 localities ranging in age from the early Oligocene to the early-late Oligocene. In addition to Eucricetodon asiaticus described in Mongolia in 1923, we have found Eucricetodon bagus and Eucricetodon jilantaiensis that were described from Nei Mongol and Eucricetodon occidentalis discovered in Kazakhstan. This taxonomical study provides new information regarding the evolution of the Cricetidae in Central and Eastern Asia during the Oligocene and, more particularly, regarding their phylogenetic relationships and the evolutionary trends. [ABSTRACT FROM AUTHOR]

Cenozoic sediments of the Taatsiin Gol and TaatsiinTsagaan Nuur area are rich in fossils that provide unique evidence of mammal evolution in Mongolia. The strata are intercalated with basalt flows. Ar/Ar data of the basalts frame the time of sediment deposition and mammal evolution and enable a composite age chronology for the studied area. We investigated 20 geological sections and 6 fossil localities of Oligocene and early Miocene deposits from this region. Seventy fossil beds yielded more than 19,000 mammal fossils. This huge collection encompasses 175 mammal species: 50% Rodentia, 13% Eulipotyphla and Didelphomorphia, and 12% Lagomorpha. The remaining 25% of species are distributed among herbivorous and carnivorous large mammals. The representation of lower vertebrates and gastropods is comparatively poor. Several hundred SEM images illustrate the diversity of Marsupialia, Eulipotyphla, and Rodentia dentition and give insight into small mammal evolution in Mongolia during the Oligocene and early Miocene. This dataset, the radiometric ages of basalt I (∼31.5 Ma) and basalt II (∼27 Ma), and the magnetostratigraphic data provide ages of mammal assemblages and time ranges of the Mongolian biozones: letter zone A ranges from ∼33 to ∼31.5 Ma, letter zone B from ∼31.5 to ∼28 Ma, letter zone C from ∼28 to 25.6 Ma, letter zone C1 from 25.6 to 24 Ma, letter zone C1-D from 24 to ∼23 Ma, and letter zone D from ∼23 to ∼21 Ma. [ABSTRACT FROM AUTHOR]

The Taatsiin Gol Basin in Mongolia is a key area for understanding the evolution and dispersal of Central Asian mammal faunas during the Oligocene and early Miocene. After two decades of intense fieldwork, the area is extraordinarily well sampled and taxonomically well studied, yielding a large dataset of 19,042 specimens from 60 samples. The specimens represent 176 species-level and 99 genus-level taxa comprising 135 small mammal species and 47 large mammals. A detailed lithostratigraphy and new magnetostratigraphic and radiometric datings provide an excellent frame for these biotic data. Therefore, we test and evaluate the informal biozonation scheme that has been traditionally used for biostratigraphic correlations within the basin. Based on the analysis of the huge dataset, a formalised biostratigraphic scheme is proposed. It comprises the Cricetops dormitor Taxon Range Zone (Rupelian), subdivided into the Allosminthus khandae Taxon Range Subzone and the Huangomys frequens Abundance Subzone, the Amphechinus taatsiingolensis Abundance Zone (early Chattian), the Amphechinus major Taxon Range Zone (late Chattian), subdivided into the Yindirtemys deflexus Abundance Subzone and the Upper Amphechinus major T. R. Z., and the Tachyoryctoides kokonorensis Taxon Range Zone (Aquitanian). In statistical analyses, samples attributed to these biozones form distinct clusters, indicating that each biozone was also characterised by a distinct faunal type. [ABSTRACT FROM AUTHOR]

We describe the remains of Aralocricetodon Bendukidze, 1993; Bagacricetodon Gomes Rodrigues et al., 2012; Eocricetodon Wang, 2007; Witenia de Bruijn et al., 2003 and Paracricetodon Schaub, 1925 (Cricetidae, Rodentia, Mammalia) from the Taatsiin Gol and Taatsiin Tsagaan Nuur areas (Mongolia). The studied material (comprising 128 teeth) stems from 9 localities and 23 fossil layers spanning a time interval from ∼33 to ∼24 Ma (early to late Oligocene) and covering the biozones from A to C1. The general dental pattern between the species from the early and late Oligocene differed. The occlusal pattern of the molars was more complicated and the crowns were lower during the early versus late Oligocene. This indicates a change in diet towards more abrasive plants. Several of the studied species were common in both Europe and Asia Minor during the early Oligocene. The species collected from the late Oligocene have also been recorded in Kazakhstan and China. This indicates an interesting biogeographical pattern that merits future study. [ABSTRACT FROM AUTHOR]

The present publication reports new discoveries of Oligocene and early Miocene aplodontid rodents from the Taatsiin Gol area (Valley of Lakes) in Mongolia. The fossil aplodontids recovered in this area are mainly composed of dental remains, some fragmentary jaws plus one partially preserved skull. Aplodontid rodents have been found from the early Oligocene (local biozone A) to the early middle Miocene (local biozone D). Altogether, eight taxa belonging to five genera have been identified in the investigated deposits: Ninamys arboraptus, Ninamys kazimierzi, Promeniscomys cf. sinensis, Prosciurus? mongoliensis and Prosciurus? sp. nov. in the early Oligocene; N. arboraptus, Proansomys badamae sp. nov. and Ansomyinae indet. in the late Oligocene; and Ansomys sp.1 in the early Miocene. In addition, although outside of the topic of the present special issue, one additional taxon, Ansomys sp.2, is reported from the ?middle Miocene. The material of aplodontids is usually relatively scarce in Asian localities. For the first time, with a sample size of 81 specimens, the material from Central Mongolia (mainly from the Oligocene) now allows a more accurate description of the morphological and size variability and resolves some systematic problems. The study of these aplodontids reveals that they are more abundant and diverse in the early Oligocene and that the diversity decreases during the late Oligocene and Miocene. One hypothesis, to explain the opposite diversity trend observed previously for sciurids in the same region, is that both Sciuromorpha families might have competed for the same resources from the early Oligocene to the middle Miocene in Central Mongolia. [ABSTRACT FROM AUTHOR]

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Additional specimens of the poorly known African shrew Lartetium africanum (Lavocat, 1961) are described and complete our knowledge of this tiny animal. The results of this study justify the elevation of material originally described as a subspecies to the species rank. Soricids are hitherto unknown in older African localities. Like many other soricids, L. africanum lived in a rather humid habitat, close to a body of freshwater, as testified by the intercalations of travertines with reeds in the lacustrine lenses that yielded the fauna. However, the presence of associated vertebrate taxa also attest to more open environments in the surroundings and a tropical climate. Various hypotheses on the date of arrival of this taxon in Africa have been proposed since migration routes between Eurasia and Afro-Arabia were not always open during the Middle Miocene and also because magnetostratigraphic data are now known and can be compared. These hypotheses are discussed here. Recent advances in our knowledge of the palaeogeography and the comparison of L. africanum with western European Lartetium taxa suggest that Beni-Mellal could be older than previously proposed, possibly early Middle Miocene. [ABSTRACT FROM AUTHOR]

Copyright of Paläontologische Zeitschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The locality of Mazan (Provence, South-Eastern France) yielded numerous remains of vertebrates, including numerous isolated teeth and a few bone fragments of mammals. A preliminary faunal list was published by Triat et al; the present systematic revision of the mammalian remains and the description of new specimens reveal that the assemblage comprises 18 taxa belonging to 7 orders and 10 families. Among the mammalian remains, the theridomyids and cricetids are the two most abundant groups. This revision confirms the ascription of the locality to the biochronological unit MP21, which corresponds to the very beginning of the Oligocene. As this locality overlies the Late Eocene faunas of Mormoiron, it clearly illustrates the drastic changes induced by the European ‘Grande-Coupure’ in Southeastern France like in the rest of Europe. A palaeobiogeographic analysis based on a comparison with 22 other Early Oligocene localities allows deciphering the European mammalian palaeobiogeography at the beginning of the Oligocene. The mammalian assemblage of Mazan shows significant affinities with other localities from Western Europe (especially French and Spanish localities), while localities from the eastern part of Europe (Anatolian, Bavarian and Bohemian localities) are noticeably different, even though these were not subjected to strong palaeobiogeographic differentiation nor endemism. The locality of Paguera 1 (Majorca)–possibly already insular in the Early Oligocene–shows peculiar affinities with Anatolian and Bavarian localities rather than with those in Western European. This, together with the absence of strong endemism, suggests the existence of land connections with the Anatolian region, but also between the Anatolian and the Bavarian regions, permitting faunal exchanges. [ABSTRACT FROM AUTHOR]

Western European Turolian mammalian faunas and palaeoenvironments are less well known than middle and early late Miocene ones for which more data exist at a time when major climate events occurred (Middle Miocene Climatic Optimum followed by Late Middle Miocene Climatic Cooling). In this respect, rich faunas represent exceptional windows into mammalian diversity and biogeography. They constitute key points to understand local palaeoenvironments and refine larger-scale patterns. Dorn-Dürkheim 1 is one of the richest mammalian faunas of Western Europe with at least 79 species of mammals. We investigate this fauna and compare its composition to the faunal and biogeographic context of the European late Miocene. A community-based analysis of body masses of the constituent species together with an original approach on predator-prey biomasses are also attempted to reconstruct its palaeoenvironment. While its composition reflects the known late Miocene context and fits in the biogeographic North-South pattern evidenced by earlier studies, the reconstructed landscape is different from previous hypotheses of densely forested habitats. Our results suggest the presence of a savanna-woodland biome more open than previously thought, in a subtropical-like and seasonal climate. Other palaeoecological studies on elements of the large mammal fauna confirm this interpretation. [ABSTRACT FROM AUTHOR]

New or poorly known Soricids from the Early Miocene of Central France (Limagne d'Allier) and from the Middle Miocene of South-Eastern France (near Lyon) are studied; one new genus (Viretia) and a new species (Carposorex burkarti) are described. The soricid assemblages of the Early and late Early/Middle Miocene localities are totally different from each other and new information about appearance and evolution of the taxa are introduced. The following are lists of studied taxa for the beginning of the Early Miocene: Clapasorex bonisi, Clapasorex aff. sigei, Carposorex burkarti nov. sp., Soricella cf. discrepans, Oligosorex aff. antiquus and Crocidosoricinae indet, and for the late Early/Middle Miocene Dinosorex sansaniensis, Dinosorex pachygnathus, Heterosorex delphinensis, Miosorex desnoyersianus, Miosorex grivensis, Lartetium dehmi, Lartetium ziegleri, Turiasorex pierremeini, Viretia nov. gen. gracilidens, Paenelimnoecus micromorphus, Paenelimnoecus crouzeli and Hemisorex robustus. [ABSTRACT FROM AUTHOR]

The mammalian fauna of the German locality Ulm-Westtangente from the Aquitanian Lower Freshwater Molasse is investigated. The fauna is compared to other rich European localities of the same time period. It is shown to be one of the richest localities for fossil mammals and brings interesting insights into the composition of the Aquitanian European faunas. Sixty-one species are identified and high affinities with the French central region are confirmed. Body mass distributions of insectivores, herbivores, omnivores and carnivores are analysed. Altogether, they showed that the environment at Ulm-Westtangente was probably a warm-temperate forest with grassland habitats, although temperature was still difficult to assess. Ulm-Westtangente lies between the Late Oligocene warm-temperate to subtropical conditions prevailing in Europe and the late Early to Middle Miocene very warm subtropical to tropical conditions of the Miocene Climatic Optimum. It thus represents an intermediate stage in the overall climatic evolution of the late Palaeogene–early Neogene of Europe. The comparison of its body mass distribution with a dataset of extant faunas indicates affinities with community structures found in nowadays temperate forests. However, the record of certain types of ectothermic vertebrates at Ulm-Westtangente precludes the presence of a typical temperate climate. The range of carnivore body masses is similar to what is known in extant communities, with species distributed in a restricted size range (small to middle sizes) in comparison to the insectivore/herbivore/omnivore species. [ABSTRACT FROM AUTHOR]

We report herein new discoveries of Gliridae and Eomyidae (Mammalia, Rodentia) from the new Early Miocene locality XJ 200604, located northwest to the Burqin city, northern Xinjiang province, China. These specimens represent three taxa of Gliridae, including a new species (Miodyromys asiamediae nov. sp., Microdyromys aff. orientalis and Eliomys? sp.), and four taxa of Eomyidae (Asianeomys aff. engesseri, Asianeomys sp., Keramidomys sp. and Eomyidae indet). The identification of two forms that are closely related to Microdyromys orientalis and Asianeomys engesseri suggests an Early Miocene age of the locality but does not allow a more precise age determination. The new discoveries of Gliridae and Eomyidae again reveal the relative scarcity of the two families in the Early Miocene of Central Asia, in contrast to the coeval rich European record. Such a discrepancy in taxonomic diversity and abundance is hypothesized as resulting from different environmental evolutions during the Early Miocene, most notably the onset of a mid-latitude dry climate in Central Asia linked to combine effects of the Tibetan Plateau uplift and the retreat of the Paratethys Sea. [ABSTRACT FROM AUTHOR]

Central Asia is a key area to study the impact of Cenozoic climate cooling on continental ecosystems. One of the best places to search for rather continuous paleontological records is the Valley of Lakes in Mongolia with its outstandingly fossil-rich Oligocene and Miocene terrestrial sediments. Here, we investigate the response by mammal communities during the early stage of Earth's icehouse climate in Central Asia. Based on statistical analyses of occurrence and abundance data of 18608 specimens representing 175 mammal species and geochemical (carbon isotopes) and geophysical (magnetic susceptibility) data we link shifts in diversities with major climatic variations. Our data document for the first time that the post-Eocene aridification of Central Asia happened in several steps, was interrupted by short episodes of increased precipitation, and was not a gradual process. We show that the timing of the major turnovers in Oligocene mammal communities is tightly linked with global climate events rather than slow tectonics processes. The most severe decline of up 48% of total diversity is related to aridification during the maximum of the Late Oligocene Warming at 25 Ma. Its magnitude was distinctly larger than the community turnover linked to the mid-Oligocene Glacial Maximum. [ABSTRACT FROM AUTHOR]