Eocene metatherians from Anatolia illuminate the assembly of an island fauna during Deep Time

Island biotas have disproportionately influenced the history and development of evolutionary biology, but understanding their genesis and evolution across geological timescales has been hindered by a poor fossil record. Here we augment the insular Eocene (~43 Ma) mammalian fauna known from the Pontide terrane of central Anatolia by describing two new metatherian taxa (stem marsupials) from the Lu¨ lu¨k Member of the Uzunc¸arşıdere Formation in the Orhaniye Basin. Geological and paleontological data indicate that the Pontide terrane was an island on the northern margin of Neotethys during the middle Eocene. Reflecting its geodynamic context in a region of active tectonic convergence, the Eocene Pontide terrane hosted a unique combination of Laurasian and Gondwanan mammals, including an anachronistic radiation of pleuraspidotheriids (archaic ungulates) that went extinct on the European mainland ~13 Ma earlier. Most of the mammalian clades occupying the Pontide terrane colonized it by dispersal across marine barriers rather than being stranded there through vicariance. Endemic radiations of pleuraspidotheriid ungulates and polydolopimorphian metatherians on the Pontide terrane reveal that in situ diversification was an important factor contributing to faunal assembly and evolution. The insular fauna that arose on the Pontide terrane is highly analogous to that of modern Sulawesi, which evolved under strikingly similar geological conditions. Illustrating the ephemeral nature of insular biotas across macroevolutionary timescales, the demise of the Pontide fauna coincided with paleogeographic changes enabling more cosmopolitan taxa to reach it for the first time. The high level of endemism shown by the mammalian fauna of the Uzunc¸arşıdere Formation eliminates the Pontide terrane as a potential early Eocene dispersal corridor between western Europe and India.INSU-2011 CT49215-12W296-13EAR- 154368

The first sawfly from the Oligocene of Céreste (Southern France) (Hymenoptera: Tenthredinidae)

Luberotenthredo cerestensis gen. et sp. nov. is the first record of the sawfly family Tenthredinidae from the Oligocene of Céreste (Southern France). This taxon is described and illustrated based on a well-preserved specimen. This genus resembles the extant genus Perineura (subfamily Tenthredininae, tribe Perineurini) with which it shares forewing venation similarities and numerous morphological characters. This new taxon is the first fossil representative of the tribe Perineurini and can be used as a calibration point for future investigation of the diversification of the family Tenthredinidae

Stepping into Oligocene. A reassessment of the early Oligocene mammal tracks from Saignon (SE France)

International audienceThe Saignon ichnosite, located in the Apt syncline, yielded a high density of footprints with hundreds of mammal tracks preserved. It was discovered and first studied in the 1970s, and never re-examined since. Here we present a new analysis of the ichnosite with updates to ichnotaxonomy. The surface of the limestone bed bearing the prints was digitised by aerial photogrammetry (UAV). Best preserved tracks and trackways were digitised by short-range photogrammetric techniques. 3D data served as the basis for all measurements, including precise depth measurements. Of the hundreds of tracks present, this study focuses on the 20 best-preserved perissodactyl trackways. A review of the large perissodactyl morphotype is provided and Rhinoceripeda voconcense comb. nov. is defined. We also present possible evidence of social behaviour in early rhinocerotids. Based on fewer tracks a second smaller perissodactyl ichnotaxon, Lophiopus isp. is identified. Artiodactyl prints are attributed, when possible, to Bifidipes velox. The Saignon tracksite, dated as early Rupelian (MP21), is at an important faunal turnover, following the Grande Coupure. Its ichnofauna is characteristic of a post-Grande Coupure fauna with the presence of newcomer rhinocerotids that reached Europe from Asia and the persistence of endemic pre-Grande Coupure palaeotheriids

Additions to the late Eocene Süngülü mammal fauna in Easternmost Anatolia and the Eocene-Oligocene transition at the periphery of Balkanatolia

The Eocene-Oligocene transition marks a period of dramatic global climatic change correlated with pronounced mammalian faunal change. Fossil evidence is indispensable for studying the distribution of taxa through time, and determining how abiotic parameters shaped ancient biodiversity. Here we report ruminant artiodactyls and a new anthropoid primate from Süngülü, a locality in Eastern Anatolia that has yielded a diversified and largely endemic assemblage of rodents. Three taxa of ­ruminants are recognized, the tragulid Iberomeryx parvus Gabunia, 1964, a larger species of Iberomeryx Gabunia, 1964, and a bachitheriid referred to cf. Bachitherium sp. A lower molar is identified as the new eosimiid primate Sungulusimias unayae n. gen., n. sp., which is the first occurrence of Paleogene anthropoids in western Asia. The lower molar of Sungulusimias unayae n. gen., n. sp. is characterized by protoconid and metaconid closely spaced and of similar height and volume, paraconid cuspidate and nearly connate with metaconid, strong mesiobuccal cingulid, and entoconid without strong connection to hypoconulid via the postcristid. The composition of this assemblage together with rodents indicates a probable Latest Eocene age for Süngülü, although an early Oligocene age cannot be completely ruled out. The rodent fauna from Süngülü suggests that endemism persisted at the periphery of Balkanatolia until the latest Eocene while Eastern Anatolia was situated in a strategic corridor for faunal exchanges between eastern Asia, Indo-Pakistan and Europe. During the Eocene-Oligocene transition, Balkanatolia probably functioned as a “holding pen” where various taxa were confined for significant intervals of time before proceeding to colonize Western Europe at the Grande Coupure

Dental anatomy, phylogenetic relationships and paleoecology of Orhaniyeia nauta (Metatheria, Anatoliadelphyidae), a Gondwanan component of the insular Eocene mammal fauna of Balkanatolia (north-central Turkey)

International audienceTwo new specimens of the anatoliadelphyid metatherian Orhaniyeia nauta are described from the middle Eocene Uzunçarşıdere Formation in the Orhaniye Basin, north-central Turkey. These specimens augment our knowledge of the dentition of this taxon, revealing that P3 and p3 of Orhaniyeia resemble those of its sister taxon Anatoliadelphys in being enlarged and highly inflated, suggesting that both taxa consumed a durophagous diet. The ancestral dental morphology of anatoliadelphyids likely approximated that of Orhaniyeia nauta, whereas the dentition of Anatoliadelphys is autapomorphous. A phylogenetic analysis incorporating the new data for Orhaniyeia reconstructs anatoliadelphyids as nested among a diverse, but generally poorly documented, assemblage of early Paleogene bunodont Gondwanan marsupials that are typically allied with polydolopimorphians. Alternative phylogenetic reconstructions based on Anatoliadelphys alone have suggested either peradectid or protodidelphid affinities for anatoliadelphyids, but these hypotheses are not supported by the new data from Orhaniyeia. Anatoliadelphyids likely colonized Balkanatolia from the south (Africa/Arabia), even though there is no current fossil record indicating that this Gondwanan bunodont marsupial clade ever inhabited Africa/Arabia. The durophagous diet of Orhaniyeia was probably eclectic, but with an emphasis on gastropods. A similar dietary reconstruction has been proposed for the Australian Miocene marsupial Malleodectes, the dentition of which is remarkably convergent with that of Orhaniyeia. Orhaniyeia and Anatoliadelphys appear to have exploited distinct ecological niches, because the autapomorphous dentition of Anatoliadelphys includes multiple specializations for enhanced carnivory. The colonization of Balkanatolia by anatoliadelphyids instigated a small endemic radiation, a pattern that was replicated by multiple other Balkanatolian mammal clades

The second oldest representative of the genus Aeshna (Odonata: Aeshnidae) found in the lowermost Oligocene of Luberon (France) and revealed by UV light

International audienceAeshna caseneuvensis sp. nov., the second oldest representative of the genus Aeshna, is described and figured from the lowermost Oligocene of Luberon in southeastern France. The oldest described species in this genus is from the uppermost Eocene of Colorado in USA. Their occurrence in very distant areas in an interval of time of less of five millions years strongly suggests that the genus is older, possibly appearing during the middle Eocene, as it is still unknown in the early Eocene odonate faunas. The specimen could be studied thanks to a technique of photograph under UV light newly developed by one of us (RG)

Caractérisation paléoclimatique de la flore rupélienne (Oligocène inférieur, MP25) de Bois d’Asson : regard croisé entre collections patrimoniales et nouvelles prospections

International audienceLa limite Éocène-Oligocène représente l'un des changements climatiques les plus importants du Cénozoïque. Au cours des dernières années, les localités paléobotaniques qui encadrent ce bouleversement environnemental ont suscité un intérêt croissant car elles permettent de caractériser quantitativement ce changement climatique. Le site rupélien de Bois d'Asson (Bassin de Manosque, Sud-Est de la France) est bien connu depuis le XIXème siècle pour la préservation exceptionnelle et l’abondance des fossiles de feuilles. Une partie de cette collection conservée à Paris a fait l’objet de nombreuses études taxinomiques notamment par Gaston De Saporta. Les ensembles floristiques comprennent des espèces paléotropicales, avec notamment des Lauraceae et des Salicaceae, mais également des espèces arctotertiaires comme des Betulaceae, certaines Fagaceae et Rhamnaceae. Dans cette étude, les 99 morphotaxons de la collection ont été analysés en utilisant la méthode CLAMP (Climate Leaf Analysis Multivariate Program) afin de reconstruire le paléoclimat du Bassin de Manosque. Les résultats indiquent que les plantes auraient évolué dans un climat froid (avec des températures pour les trois mois les plus froids proches de 0°C), humide (précipitations élevées) et à saisonnalité marquée, ce qui contraste avec les résultats climatiques attendus pour cette zone paléogéographique (températures élevées et aridité marquée). Une nouvelle campagne de fouilles en mars 2022 a permis de préciser la localisation des niveaux fossilifères, la technique de récolte et de tri des échantillons. L’étude combinée de la sédimentologie et de la taphonomie a montré que l’ensemble floristique de la collection patrimoniale est issu de différents faciès qui représentent un même environnement. Les résultats inattendus pourraient ainsi être dus à la composition particulière des communautés végétales et aux limites de la calibration de la méthode CLAMP

Caractérisation paléoclimatique de la flore rupélienne (Oligocène inférieur, MP25) de Bois d’Asson : regard croisé entre collections patrimoniales et nouvelles prospections

International audienceLa limite Éocène-Oligocène représente l'un des changements climatiques les plus importants du Cénozoïque. Au cours des dernières années, les localités paléobotaniques qui encadrent ce bouleversement environnemental ont suscité un intérêt croissant car elles permettent de caractériser quantitativement ce changement climatique. Le site rupélien de Bois d'Asson (Bassin de Manosque, Sud-Est de la France) est bien connu depuis le XIXème siècle pour la préservation exceptionnelle et l’abondance des fossiles de feuilles. Une partie de cette collection conservée à Paris a fait l’objet de nombreuses études taxinomiques notamment par Gaston De Saporta. Les ensembles floristiques comprennent des espèces paléotropicales, avec notamment des Lauraceae et des Salicaceae, mais également des espèces arctotertiaires comme des Betulaceae, certaines Fagaceae et Rhamnaceae. Dans cette étude, les 99 morphotaxons de la collection ont été analysés en utilisant la méthode CLAMP (Climate Leaf Analysis Multivariate Program) afin de reconstruire le paléoclimat du Bassin de Manosque. Les résultats indiquent que les plantes auraient évolué dans un climat froid (avec des températures pour les trois mois les plus froids proches de 0°C), humide (précipitations élevées) et à saisonnalité marquée, ce qui contraste avec les résultats climatiques attendus pour cette zone paléogéographique (températures élevées et aridité marquée). Une nouvelle campagne de fouilles en mars 2022 a permis de préciser la localisation des niveaux fossilifères, la technique de récolte et de tri des échantillons. L’étude combinée de la sédimentologie et de la taphonomie a montré que l’ensemble floristique de la collection patrimoniale est issu de différents faciès qui représentent un même environnement. Les résultats inattendus pourraient ainsi être dus à la composition particulière des communautés végétales et aux limites de la calibration de la méthode CLAMP

New fossils from the Paleogene of central Libya illuminate the evolutionary history of endemic African anomaluroid rodents

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