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... The Euzet-les-Bains site, which is early late Eocene in age like the Roc de Santa site, is in southeastern France (Figs. 1A-B), approximately 400 km southeast of the sites of Villebramar and St. Capraise d'Eymet. Among the recovered fossils are aquatic plants and fish (Depéret, 1917;Aguilar et al., 1997), which suggests a nearby water source. ...
... According to several palaeontological studies, the site of St. Capraise d'Eymet (Dordogne, France) is assigned to level MP 20, but as the fossil assemblage of this site is quite poor in micromammal fossils, it is not a particularly good landmark (Aguilar et al., 1997;Gagnaison and Leroux, 2013). Villebramar would have been dry open woodland associated with marshy forests and an open, dry environment, probably a scrub woodland type, according to the Ronzotherium-Anthracotherium association (Uhlig, 1999;Emery et al., 2007;Becker et al., 2009). ...
... The biochronological scale used in this paper is the Mammal Palaeogene (MP) reference levels (Schmidt-Kittler, 1987;Aguilar et al., 1997). We use the traditionally accepted ages for the chronostratigraphy of the MP levels of Europe (more details in Badiola et al., 2009). ...
The climatic cooling that began in the late middle Eocene and culminated in the Eocene-Oligocene transition meant major changes in Palaeotheriidae (Perissodactyla, Mammalia) biodiversity in Europe and could have caused the appearance of new dietary strategies. This work is the first to study the spatiotemporal response of one palaeotheriid genus (Plagiolophus) to the Eocene environmental and ecological changes using three dietary proxies: hypsodonty, mesowear and dental microwear texture analysis (DMTA). DMTA is applied for the first time to palaeotheriids. The high diversity and wide chrono-spatial distribution of Plagiolophus make it possible to evaluate spatiotemporal environmental variations, including palaeodiet. We study five Plagiolophus samples from late middle Eocene to early Oligocene from western Iberia to central Europe in order to (1) infer lifetime palaeodiet; (2) infer short-term palaeodiet; and (3) test temporal and spatial trends. All samples present an exclusion of abrasive foodstuff given low hypsodonty index; dominance of browsing given the low mesowear score; and browsing of tough foliage and exclusion of hard items in their diet given DMTA information. These factors point to Plagiolophus as a highly selective feeder that fed on plants with the same features irrespective of chronology or location: tough foliage (leaves from monocots or dicots) avoiding lignified or hard materials, without seasonal variations.
... However, data regarding the early Eocene are unfortunately scant. The locality of Dormaal in Belgium represents one of the rare exceptions, serving as a window to the earliest Eocene (MP 7 reference level of the mammalian biochronological scale for the European Palaeogene; BiochroM'97 [2]) 'greenhouse world'. The early Eocene is particularly interesting because the Eocene climate began with a rapid and intense warming called the Palaeocene-Eocene thermal maximum (PETM), which is marked by the Palaeocene-Eocene carbon isotope excursion (CIE), 56 Ma. ...
... It belongs to the lower part of the fluvio-lagoonal Tienen Formation that recorded the CIE of the PETM and contains abundant remains of terrestrial mammals and lizards, freshwater fish, chelonians and crocodylians. The Dormaal fauna, which represents the reference-level MP7 (BiochroM'97 [2]), has already yielded numerous mammal taxa, including the earliest modern placental mammals of Europe [41][42][43]. ...
We here describe a new gekkotan lizard from the earliest Eocene (MP 7) of the Dormaal locality in Belgium, from the time of the warmest global climates of the past 66 million years (Myr). This new taxon, with an age of 56 Myr, together with indeterminate gekkotan material reported from Silveirinha (Portugal, MP 7) represent the oldest Cenozoic gekkotans known from Europe. Today gekkotan lizards are distributed worldwide in mainly warm temperate to tropical areas and the new gecko from Dormaal represents a thermophilic faunal element. Given the Palaeocene–Eocene thermal maximum at that time, the distribution of this group in such northern latitudes (above 50° North – the latitude of southern England) is not surprising. Although this new gekkotan is represented only by a frontal (further, dentaries and a mandibular fragment are described here as Gekkota indet. 1 and 2—at least two gekkotan species occurred in Dormaal), it provides a new record for squamate diversity from the earliest Eocene ‘greenhouse world’. Together with the Baltic amber gekkotan Yantarogekko balticus , they document the northern distribution of gekkotans in Europe during the Eocene. The increase in temperature during the early Eocene led to a rise in sea level, and many areas of Eurasia were submerged. Thus, the importance of this period is magnified by understanding future global climate change.
... Here we describe the endocranium of the holotype of Eurotherium theriodis (Van Valen, 1965). This hyaenodont is from the Lutetian (Eocene) of Europe (Egerkingen, Switzerland, MP13?-MP14; Aigues-Vives 2, France, ?MP13; MP = Mam mal Paleogene reference level of the mammalian biochronological scale for the European Paleogene; Aguilar et al. 1997) (Van Valen 1965Solé et al. 2015;Figs. 1, 2). ...
... Three infillings have been excavated since 1890: these are designated α, β, and γ. Quarries α and β constitute the reference locality of reference level MP14 (generally noted as Egerkingen α + β), while Quarry γ is considered to be slightly older and referred with uncertainty to MP13? (Aguilar et al. 1997), possibly close to the MP13 reference level. Therefore, all the infillings are Lutetian (middle Eocene) in age. ...
Hyaenodonts are extinct placental mammals with a carnivorous diet. Their phylogenetic position among mammals and the relationships within Hyaenodonta are at present partially unresolved. The endocranium is a structure that has rarely been studied in this clade. Using 3D tomography, we studied the endocranium of the European hyaenodont Eurotherium theriodis, discovered in Egerkingen (Switzerland, Lutetian, middle Eocene). Eurotherium theriodis has an endocranium morphology that supports an increase in size of the cerebrum relative to the cerebellum over time within the Hyaenodontoidea. The endocranium also supports a complexification of the cerebrum (i.e., at least two furrows per cerebral hemisphere) within the Hyaenodontoidea and allows us to envisage an increase of the encephalization quotient (EQ), over time. Based on morphology, we consider that its endocranium does not depart from that of the hyaenodontoids known in the Lutetian, Bartonian, and Priabonian of Europe, being less complex than that of the hypercarnivorous Hyaenodon. However, the morphology of its olfactory bulbs and turbinates is similar to that observed in Hyaenodon. The large size of the turbinates of E. theriodis is regarded to be the result of a possible scavenger ecology and agrees with the meat/bone diet envisaged based on the analysis of the morphology of the skull and teeth.
... Therefore, the precise age of the fossils often is uncertain (de Bonis, 1974, 2011, andreferences therein). However, the sediments of Mas de Got B were correlated with the MP 22, and thus represent the oldest of the fossil localities studied herein; Roqueprune 2 was correlated with the slightly younger MP 23 (Schmidt-Kittler et al., 1987;Aguilar et al., 1997). Therefore, both localities represent Rupelian deposits. ...
... The quarry of Coderet is in contact with the western border fault of Limagne (Hugueney, 1969;de Bonis et al., 1999). It was correlated to MP 30 (Schmidt-Kittler et al., 1987;Aguilar et al., 1997) and is therefore of Chattian age. La Colombi ere is located in the D epartement H erault in the suburbs of the city of Montpellier. ...
Several extinct species are known from the family Lacertidae, but due to poor preservation, many of them are based on single bones. Here, we compare phylogenetic signals of disarticulated premaxillae, maxillae and dentaries of lacertids from four French Oligocene localities (Coderet, La Colombière, Roqueprune 2, Mas de Got B). We identified five morphotypes among the premaxillae, six among the maxillae, and ten among the dentaries. These morphotypes were scored as individual taxa per locality into three separate character matrices with the same 246 characters, one matrix for each jaw element. Subsequently, the phylogenetic position of the morphotypes was tested using maximum parsimony. The consensus trees with the dentaries and the maxillae found a large polytomy including all taxa except the outgroup taxon Gekko gecko. The consensus tree with the premaxillae showed a considerably more resolved topology but found all morphotype taxa outside Lacertidae. In a second step, we compared the constitution of our three datasets and the morphotype taxa. Our results suggest that a combination of convergent characters and missing data led to the outgroup position of the premaxilla morphotype taxa. The poor resolution of the maxillae strict consensus is likely a consequence of their fragmentary preservation. For the dentaries, a high amount of missing data due to the high number of morphotype taxa most likely caused the poor tree resolution. Indeed, tests with fewer morphotypes found tree resolutions comparable to the premaxilla data. When linking the morphotypes, five possible lacertid “species” were found. Comparison with already known French Oligocene lacertid species points to a slightly higher species richness of Lacertidae at that time than known before. Reliable species classification based on phylogeny only seems possible when combining the jaw elements or in association with other cranial and postcranial material, putting some doubt on species identifications based on single bones.
... This species was defined by shell remains from the Lutetian of Sanzoles (Zamora) (see Jiménez-Fuentes 1992b). The material attributed to it corresponds Aguilar et al. 1997). PC: Polarity Chron (Geomagnetic Polarity Scale). ...
The Palaeogene sedimentary successions of the Duero Basin host an important record of fossil vertebrates, especially mammals and reptiles. The main fossil sites are placed at the west margin (Salamanca and Zamora areas) spanning from the Lutetian to the late Priabonian; and at the southeast tip (Almazán Basin) mainly Bartonian in age. The continued study of the sites is supplying new data that will improve the chronostratigraphy and the correlation between the western and eastern regions of the basin. The diversity and phylogenetic relationships of the represented fauna have been revised in recent years with the reassignment of some remains and the diagnosis of some new taxa. Four lineages of turtles are represented: Podocnemididae (Neochelys), Carettochelyidae (Allaeochelys), Trionychidae and Testudinidae (Pelorochelon). Crocodyliform paleobiodiversity is composed of notosuchians (close to Iberosuchus) and, at least, three crocodylian lineages: Planocraniidae (Duerosuchus), Alligatoroidea (Diplocynodon) and Crocodyloidea (‘Asiatosuchus’). The distribution of these taxa is not homogeneous throughout the basin, and a deep transformation is recognised throughout the middle Eocene. The fitting of the distribution and relationships of the reptilian fauna from the Duero Basin provides valuable information to understand some faunistic dynamics such as the endemism process of northwestern Iberia from the middle of the Eocene.
... One of the most intriguing perissodactyl families is the extinct family Palaeotheriidae Bonaparte, 1850(Equoidea Gray, 1821, named after the genus Palaeotherium described in 1804 in the Montmartre quarries (Paris) by the French naturalist George Cuvier. The fossil record of the paleotheres (or pseudohorses sensu Franzen, 2010), which comprise the genera Palaeotherium and Plagiolophus Pomel, 1847 and relatives, covers a temporal range from the middle Eocene to the early Oligocene in different areas of the European archipelago (e.g., Aguilar et al., 1997;Badiola et al., 2009b;Danilo et al., 2013;Métais and Sen, 2017) (Fig. 1A). ...
The middle and late Eocene perissodactyl fossil record of western Iberia is characterized by an endemic fauna, which is clearly different from those of northeastern Iberia and other areas of the European archipelago. In this work, we describe three endemic equoid taxa belonging to the family Palaeotheriidae. Two come from the late Eocene site of Zambrana (Miranda-Treviño Basin, Araba/Álava, Spain) and correspond to new species: Leptolophus cuestai, sp. nov., and Leptolophus franzeni, sp. nov. Leptolophus cuestai, sp. nov. is the largest species of Leptolophus and exhibits thick coronal cementum and a very high hypsodonty index, unusual for an Eocene equoid. Leptolophus franzeni, sp. nov. is described from a cranium which includes the canines, which are otherwise unknown in Leptolophus. The third taxon, from the late middle Eocene site of Mazaterón (Almazán Basin, Soria, Spain), described provisionally as Leptolophus sp., could be another new Iberian species. The Iberian taxa are characterized by having: more hypsodont, lophodont and heterodont dentition than the Central European Leptolophus taxa (L. stehlini, L. nouleti and L. magnus); thicker styles and stylar ribs in the upper jugal teeth; and thicker coronal cementum. The precocious development of coronal cementum and the high hypsodonty index could be related to different foraging conditions (tougher vegetation, more open or drier habitats with a higher consumption of grit in the diet) inhabited by the Iberian Leptolophus species with respect to their Central European contemporaries.
http://zoobank.org/urn:lsid:zoobank.org:pub:03F87D46-2320-41D2-AE08-333866F005AD
A collection of approx. 150 isolated cheek teeth of the eomyid rodent Eomys antiquus which was obtained from a very thin layer in the Hamstead Member of the Bouldnor Formation at Bouldnor Cliff (Isle of Wight, England, UK) is described. The material is post-Grande Coupure, and earliest Oligocene in age. Comparison is made with and new data are given on teeth of Eomys from localities of a similar age situated elsewhere in Europe: Eomys antiquus from Hoogbutsel (Belgium), and Möhren 13, 19, and 20 (Germany), and Eomys aff. antiquus from Montalbán 1D (Spain), and Kocayarma (Turkish Thrace, Turkey). Teeth from Bouldnor Cliff and Hoogbutsel (Mammal Paleogene zone 21) are morphologically close to those from Möhren 13 (Mammal Paleogene zone 22), but tend to be larger. Size decrease in the course of time is also suggested by the smaller size of the teeth from Montalbán 1D (Mammal Paleogene zone 23). The morphological differences observed between the English, Belgian, and German material at the one side, and the Spanish and Turkish material at the other, confirm that the species from Montalbán 1D and Kocayarma is a different, although closely related form. The taxonomic history of Eomys antiquus is reviewed. The species is the commoner of the two oldest European Eomyidae known. General knowledge on the ecology of the eomyids suggests that at the time of deposition of the Eomys -containing layer in the Hampshire Basin forest was close by.
The generic status of the species referred to Protadelomys has long been problematic. Most Protadelomys species are now considered paraphyletic, except for the type species P. cartieri and for P. lugdunensis . Here, we revised these two species from their type locality, Egerkingen (Swiss Jura) for P. cartieri and Lissieu (Rhône, France) for P. lugdunensis . For the latter species, we also consider the locality of Laprade (Tarn-et-Garonne, Quercy, France). Additionally, we revised the material attributed to Protadelomys species that is now considered paraphyletic: ? P. alsaticus from Bouxwiller (Bas-Rhin, France) and Cuzal (Lot, Quercy, France), ? P. maximini from St-Maximin (Gard, France), and ? P. nievesae from Casa Ramon (Huesca, Spain). Our detailed morphological analysis enables us to better characterize the extent of the morphological and size variability in all Protadelomys and ? Protadelomys species. We show that both P. cartieri and P. lugdunensis co-existed in Egerkingen, Lissieu, and Laprade. We also erected a new genus and species, Homœtreposciurus egerkingensis , and reported the presence of Eoelfomys from Egerkingen. Eoelfomys is here described as a new genus and species from Laprade. Size and morphological comparisons enabled us to detect large intraspecific variation in the material of ? P. alsaticus from Bouxwiller, as well as in the type population of ? P. maximini . The co-occurrence of the two Protadelomys species, at least in two localities, in addition to the revision of the features characterizing the three species of ? Protadelomys , led us to question the existence of a single evolutionary lineage (chronospecies), as previously recognized from ? P. maximini to P. lugdunensis .
This review provides a synthesis of the evolution of the Pyrenees since ~84 Ma and is uniquely focused on analysing jointly and comparatively its peripheral pro-foreland, retro-foreland and Mediterranean basins. The reconstructions adopt a geomorphological perspective focused on the waxing and waning of palaeorelief, and is underpinned by (i) the denudation history of the mountain belt encoded in the sedimentary record of its basins, (ii) rock-cooling histories inferred from low-temperature thermochronology, and (iii) the age and spatial distribution of tectonic and erosional landforms. Existing geological reconstructions of the Pyrenees commonly terminate at the end of the syntectonic collision period (early Miocene). Here, the no-less eventful post-shortening period of the last 25–30 m.y. is also addressed. Accordingly, emphasis is given to the record provided by nonmarine clastic sequences, and to the often understated depositional biochronology documented by the continental fossils they contain. Sedimentological and provenance analysis of coarse clastic deposits further documents the fine-scale palaeogeography of sources and sinks, and is correlated with different generations of eustatic, tectonic, and volcanic features, as well as extant populations of land surfaces such as rock pediments, palaeovalleys, and other landforms indicative of palaeoelevation and palaeotopography. These interconnected and age-bracketed diagnostic features are correlated with independent evidence concerning the structural evolution of the orogenic belt at crustal and lithospheric scale. They show that the Ancestral (i.e., Paleogene) Pyrenees were in many aspects dissimilar to the successor mountain range we observe today. They also suggest that, despite its prima facie topographic continuity from the Mediterranean to the Atlantic, the modern mountain range, particularly in its eastern half, is in a transient topographic state. This would appear to have been driven by large-scale asthenospheric flows contributing to regional uplift and erosion of not just the mountain range but also its foreland basins during the last ~12 m.y.
Since its first erection almost 200 years ago, palaeontologists have assigned to the genus Anthracotherium many species, some with dubious descriptions. Although it is a key taxon for specifying the invasion of Europe by terrestrial mammals during the well-studied Grande Coupure Event at the beginning of the Oligocene, the genus has never been reviewed before. A recent interest in the relationships of anthracotheres and hippopotamids highlighted its importance for the understanding of diversity of anthracotheres. Herein, we conduct a systematic review of most European anthracotheriine species, including some Asian and American species in order to establish a more exhaustive anthracotheriine phylogeny. A cladistic analysis focusing on anthracotheriines supports us in redefining and clarifying the systematic status of most genera and species of this subfamily. Furthermore, our study results in the division of Anthracotherium into two different genera, the definition of a new taxon, Paenanthracotherium gen. nov., and the creation of a new species from previously described material, Paenanthracotherium bergeri sp. nov. Additionally, our phylogeny suggests a new palaeogeographical scenario implying several dispersal events from Asia to Europe before and during the Grande Coupure Event. This study marks the first step to a much-needed global review of anthracotheriines, including the American and Asian specimens.
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