Crocodilian remains from the late Palaeocene continental locality of Mont de Berru (Marne, France) offer the opportunity to reassess the taxonomic identity of the oldest diplocynodontid from Europe. Owing to significant morphological differences from previously described species of Diplocynodon, which include the presence of a splenial symphysis, a new species, Diplocynodon remensis sp. nov., is erected here. Its inclusion in a phylogenetic framework for Eusuchia leads to its positioning as a derived member of diplocynodontids. Diplocynodontidae are viewed as a basal alligatoroid taxon, and, because morphological affinities with the Late Cretaceousâearly Eocene North American genus Borealosuchus were mentioned in earlier studies, a comparison amongst D. remensis sp. nov., Leidyosuchus, and Borealosuchus spp. is presented. Although D. remensis sp. nov. is the geologically oldest diplocynodontid, according to our results, it is not the phylogenetically most primitive. Other morphological discrepancies are highlighted, indicating that the topology recovered here is only tentative. From a biogeographical point of view, the appearance of Diplocynodon in Europe prior to the Palaeocene/Eocene boundary indicates that it did not disperse with North American taxa that reached Europe around the time of the Palaeocene-Eocene thermal maximum (PETM). Therefore, a pre-PETM dispersal from North America at the same times as other vertebrates with clear North American affinities also occurring in the Palaeocene of Europe cannot be excluded. The description of D. remensis sp. nov. adds substantial new, albeit conflicting, information, highlighting the need for a better phylogenetic framework with a revision of other critical taxa (Menatalligator, Borealosuchus) from the Palaeocene of Europe and North America.
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As part of a rock art dating project at Qurta (Upper Egypt), samples were collected from an organic deposit and from an accumulation of individual faecal pellets. Radiocarbon dating of these relatively well-preserved materials indicates an unexpectedly old age of ca. 45,000 BP or older. In order to identify the biogenic nature of these deposits and to reconstruct the palaeo-environment at the time of their formation, micromorphological, palaeobotanical, and biomarker analyses were carried out. All data indicate that the organic deposit and the pellets were produced by different species. The presence of a novel biomarker, which only occurs in animal urine (hippuric acid), contributed to the conclusion that the organic deposit most likely represents the remains of a rock hyrax (Procavia capensis) latrine, whereas the pellets stem from small bovids. Plant macroremains from the pellets indicate that the animals browsed in the more vegetated areas, presumably near the Nile, although the general environment was probably mainly arid and open. Combined with the dates, this suggests that the pellets date to MIS 3 or 4. Our results demonstrate the great potential of an interdisciplinary approach to the study of Quaternary coprolite deposits, allowing for more adequate and more complete interpretation.
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RBINS Staff Publications 2018
