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We studied at least part of Kuhnʼs original material of lizards from the Paleocene (~ MP 5) of the Walbeck locality in Germany. The collection was considered to be lost but is consistently discussed in the literature due to its importance. We restudied the type material of aff. Parasauromalus paleocenicus and aff. Glyptosaurus walbeckensis described by Kuhn in 1940. The former was originally allocated to Iguania, the latter to Anguimorpha, though later on these identifications were questioned by several authors. We show such a classification of both cannot be upheld. P. paleocenicus resembles the morphology of lacertids showing their presence in Europe already around MP 5. We consider the name P. paleocenicus as a nomen dubium. The material of aff. G. walbeckensis was later suggested to belong to Lacertidae and also considered as a potential amphisbaenian. Although it differs from modern amphisbaenians, it shares features with one supposed polyodontobaenid – Camptognathosaurus parisiensis. The Walbeck form is identical to this species. Since the Walbeck taxon was described in 1940, the principle of priority makes Camptognathosaurus parisiensis a junior synonym of the species erected by Kuhn. We propose a new combined name for this form, Camptognathosaurus walbeckensis comb. nov. The specimen figured by Kuhn is currently lost, thus we designate a neotype from Walbeck. However, this taxon differs significantly from Polyodontobaena and new data doubt the attribution of Camptognathosaurus to Amphisbaenia. This taxon is tentatively assigned here to Lacertidae, as further confirmed by phylogenetic analyses. Material of Scincoidea is also described. [ABSTRACT FROM AUTHOR]

We describe nearly complete skeletons of basal Anseriformes from the Latest Paleocene to the early Eocene of North America and Europe. Collectively, these birds appear to be representative of anseriforms near the divergence of Anhimae and Anseres, but their exact positions relative to these clades remains uncertain. A new family, Anachronornithidae nov. fam., is erected on the basis of one of these, Anachronornis anhimops nov. gen., nov. gen. et sp., to which the others cannot be confidently assigned. The new fossils augment a growing collection of early Pan-Anseriformes, which in their diversity do not paint an unambiguous picture of phylogeny or character state evolution on the path to or within crown-Anseriformes. Anachronornis nov. gen. is similar in some aspects of both cranial and postcranial anatomy to other well-represented early Paleogene Anseriformes and members of Anseres, such as Presbyornis Wetmore, 1926. However, it exhibits a more landfowl-like bill, like that of Anhimae and unlike the spatulate bill of Anseres. Additional specimens of similar basal Anseriformes of uncertain affinities from the early Eocene of North America and Europe further complicate interpretation of character state polarity due to the mosaicism of primitive and derived characters they exhibit. [ABSTRACT FROM AUTHOR]

Saniwa is an extinct genus of varanid squamate from the Eocene of North America and Europe. Up to now, only one poorly known species, Saniwa orsmaelensis Dollo, 1923, has been reported from Europe. Diagnostic material was limited to vertebrae with only preliminary description and no figure provided, except of one dorsal vertebra that was designated as the lectotype. New specimens from the earliest Eocene of Dormaal, Belgium and Le Quesnoy, France, including recently recovered skull material, are described and illustrated here. These fossils representing the oldest varanid squamate allow further comparisons with the type species, Saniwa ensidens Leidy, 1870, from the early and middle Eocene of North America and to propose a new diagnosis for S. orsmaelensis. Its arrival in Europe is probably linked to rapid environmental changes around the Paleocene Eocene Thermal Maximum (PETM). The occurrence of S. orsmaelensis is restricted to the early Eocene of northwest Europe and paleogeographic considerations regarding the distribution of the genus Saniwa Leidy, 1870 suggest an Asian origin, but an African origin cannot be completely excluded. [ABSTRACT FROM AUTHOR]

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, D iplocynodon 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 Cretaceous−early 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. © 2014 The Linnean Society of London [ABSTRACT FROM AUTHOR]

Abstract: Environmental changes associated with the Paleocene–Eocene thermal maximum (PETM, ∼56Ma) have not yet been documented in detail from the North Sea Basin. Located within proximity to the North Atlantic igneous province (NAIP), the Kilda Basin, and the northern rain belt (paleolatitude 54°N) during the PETM, this is a critical region for testing proposed triggers of atmospheric carbon release that may have caused the global negative carbon isotope excursion (CIE) in marine and terrestrial environments. The CIE onset is identified from organic matter δ 13C in exceptional detail within a highly expanded sedimentary sequence. Pollen and spore assemblages analysed in the same samples for the first time allow a reconstruction of possible changes to vegetation on the surrounding landmass. Multiproxy palynological, geochemical, and sedimentologic records demonstrate enhanced halocline stratification and terrigenous deposition well before (103 yrs) the CIE, interpreted as due to either tectonic uplift possibly from a nearby magmatic intrusion, or increased precipitation and fluvial runoff possibly from an enhanced hydrologic cycle. Stratification and terrigenous deposition increased further at the onset and within the earliest CIE which, coupled with evidence for sea level rise, may be interpreted as resulting from an increase in precipitation over NW Europe consistent with an enhanced hydrologic cycle in response to global warming during the PETM. Palynological evidence indicates a flora dominated by pollen from coastal swamp conifers before the CIE was abruptly replaced with a more diverse assemblage of generalist species including pollen similar to modern alder, fern, and fungal spores. This may have resulted from flooding of coastal areas due to relative sea level rise, and/or ecologic changes forced by climate. A shift towards more diverse angiosperm and pteridophyte vegetation within the early CIE, including pollen similar to modern hickory, documents a long term change to regional vegetation. [Copyright &y& Elsevier]

Improved knowledge of the diversity of Late Paleocene mammal faunas of NW Europe indicates a higher level of turnover at the Paleocene-Eocene boundary than previously recognized. Possible causes of the large number of extinctions in Europe are investigated through ecological diversity analysis of the mammals and the plant fossil record. Predation by incoming ground- and tree-dwelling specialized carnivores has been previously considered the main cause of the extinctions. However, the preferential extinction of small terrestrial and semiterrestrial insectivore-frugivores, (mainly stem macroscelideans and multituberculates), which are inferred to have inhabited forests with dense understorey in the Paleocene, is also linked to the arrival in Europe of a new ecological type, the large terrestrial browsing herbivore, namely the pantodont Coryphodon, which would have reduced understorey by feeding and physical disturbance. It is suggested that there was a delay in community evolution in Europe, which in North America had previously produced large herbivorous and specialized carnivorous types. The cause of the delay may have been the persistence throughout the Paleocene in Europe of thermophilic evergreen forests despite the cooling in the middle of the epoch. This contrasted with North America, where more open deciduous forests developed in the continental interior and provided the selection pressure for the new ecological types of mammal. [ABSTRACT FROM AUTHOR]