Jean-Pierre Berger

Taxonomy and phylogeny of the turtle Tropidemys langii Rütimeyer, 1873, based on new specimens from the Kimmeridgian of the Swiss Jura Mountains

ABSTRACT The fossil turtle Tropidemys langii is a representative of Plesiochelyidae, a traditionally recognized group of Late Jurassic turtles diagnosed by the presence of three cervical scutes and adapted to life in the sea. Tropidemys langii was previously only known from fossilized carapaces and, possibly, plastra from Europe, most notably the famous ‘Solothurn Turtle Limestone’ of Switzerland. Due to the sparse fossil record of Tropidemys langii, several questions concerning its taxonomy and phylogeny have remained unanswered. Here, new material of Tropidemys langii is reported from the Kimmeridgian of Porrentruy, Canton Jura, Switzerland. In addition to three well-preserved carapaces, associated plastra and limb bones (humerus and femur) are described for the first time. The type specimens of ‘Tropidemys valanginiensis’ and ‘Pelobatochelys blakii’ lack diagnostic characters, but can nevertheless be referred to Tropidemys. A potential extension of the lineage into the Early Cretaceous is uncertain, however, because the type locality of ‘Tropidemys valanginiensis’ is dubious. A cladistic analysis shows that Tropidemys langii is sister to Plesiochelys solodurensis, thereby tentatively confirming for the first time the monophyly of Plesiochelyidae using cladistic arguments.

Stable isotopes (δ13C and δ18O) of charophyte gyrogonites: example from the Brochene Fluh section (Late Oligocene–Early Miocene, Switzerland)

Abstract A synthetic curve based on the δ13C and δ18O variation measured on Oligocene–Miocene charophyte gyrogonites is presented. Such a synthetic curve cannot be interpreted without taking into account facies relationships. Thus, we present a detailed analysis of the Brochene Fluh section (Late Oligocene, MP29, to early Miocene, MN1), in which more than 30 charophytes levels have been recorded. It is possible to subdivide the section into six cycles: cycles one to four, Late Oligocene in age, present a covariance in the δ13C and δ18O variation, and are typical of small closed lakes subject to great seasonal changes (especially humidity). The last two cycles, of Aquitanian age, show a diminution of seasonality perhaps due to the ingression of the future Burdigalian sea.

Large mammals from Rickenbach (Switzerland, reference locality MP29, Late Oligocene): biostratigraphic and palaeoenvironmental implications

Since the first exploitation of the Huppersandstones quarry of Rickenbach (Canton Solothurn, Switzerland) in 1898, many fossils of plants, molluscs, and vertebrates have been discovered. The study of the small mammals brought this locality to international recognition as the type locality for the European mammalian reference level MP29 (latest Oligocene). Our study reviews the terrestrial herbivorous mammals of Rickenbach and aims to reconstruct the palaeoenvironmental and palaeoclimatic conditions in which they lived. The perissodactyls and cetartiodactyls are described and identified: Protapirus sp. (Tapiridae), Ronzotherium romani and Diaceratherium lamilloquense (Rhinocerotidae), Anthracotherium magnum and Microbunodon minimum (Anthracotheriidae), Palaeochoerus pusillus (Suoidea), and Dremotherium guthi, “Amphitragulus” quercyi, “Amphitragulus” feningrei, and Babameryxengesseri gen. et sp. nov. (Ruminantia). Based on the updated faunal list, a cenogram of the locality of Rickenbach is established. We also performed ecomorphologic analyses on ruminants and rhinocerotids. The reconstructed palaeoenvironment of Rickenbach probably corresponded to a savannah woodland affected by a subtropical climate with clear seasonality.

Tapiridae (Perissodactyla, Mammalia) of the Swiss Molasse Basin During the Oligocene—Miocene Transition

Abstract The Tapiridae of the Swiss Molasse Basin from the late Oligocene to the early Miocene are reviewed. Fossil remains that have not previously been described are identified, old descriptions and identifications from previous works are reassessed, and specimens from Switzerland and France are compared, specifically Protapirus bavaricus from Ebnat-Kappel (MP28) and Rüfi bei Schünis (MP29), Protapirus aginensis from La Milloque (France, MP29), Protapirus douvillei from Buchberg 6 (MN4), Paratapirus helvetius from Haslen (Switzerland, MP28-30), Paratapirus intermedius from Saulcet (France, MN1), Höhronen (MN1), and Brüttelen 1 (MN3a), and Eotapirus broennimanni from Wischberg (MN1) and Benken (MN3-4?). These new data enable emended specific diagnoses for Protapirus bavaricus, P. aginensis, and P. douvillei. A late Oligocene (MP28-30) age for the locality of Haslen—the neotype locality of Paratapirus helvetius—is also attributed, based upon the literature and personal observations. Furthermore, a new and precise biostratigraphic range of the European Tapiridae at the species level is proposed for the Oligocene and early Miocene of Western Europe. The paleoecology of tapirs and their diversity and evolution through the Oligocene—Miocene transition are discussed and compared with contemporaneous large mammals such as Rhinocerotoidea, Anthracotheriidae, and Suoidea.

Reworked microfossils as a paleogeographic tool

The abundant occurrence of reworked microfossils within the paleogeographically restricted Upper Rhine Graben of central Europe represents a unique opportunity to investigate their inherent information, allowing new insights into the paleogeographic framework and past sedimentary pathways. In the late Rupelian and early Chattian a transgression-regression cycle linked to the global Ru2–Ru3 sequences affected the entire Upper Rhine Graben basin, leading to the deposition of a thick marine to lacustrine series. The occurrences of abundant reworked planktonic foraminifera are grouped into several events that are linked to intervals of increased clastic input during regressive phases. The biostratigraphic ranges of the reworked taxa indicate Late Cretaceous, Ypresian, Lutetian, and Bartonian–Priabonian ages for the sediment sources. The reworking originated from related west alpine source deposits via a northward-draining fluviatile system. A fast uplift of Priabonian and older deposits within the alpine realm during the late Rupelian is accordingly inferred, confirming the increased rate of the mesoalpine orogeny at that time. The careful analysis of reworked microfossil assemblages thus provides a valid tool for future paleogeographic, tectonic, and provenance studies.

The position of the Rupelian/Chattian boundary in the southern Upper Rhine Graben based on new records of microfossils

This study analyses the regressive phase of the marine Froidefontaine Subgroup and the subsequent fluvio-lacustrine Niederroedern formation in the southern Upper Rhine Graben during the Late Rupelian and the position of the Rupelian/Chattian boundary. The study is based on the sedimentary record and several microfossil groups from two boreholes, with a focus on new records of fish otoliths, Bolboforma and Charophyta. The biostratigraphic evaluation of these groups provides evidence for a position of the Rupelian/Chattian boundary within the upper Niederroedern Formation. This is contrary to the results from a previous sedimentological approach, which places the boundary at the base of the Niederroedern Formation. The fish fauna indicates a biogeographic relation to southern France, the Molasse Basin of Switzerland and southern Germany.

Un curieux microfossile de la Molasse oligocène de Suisse occidentale et de Haute-Savoie (France)

RésuméNouvelle description de l’incertae sedis Calcicarpinum? fallax. Détermination de son âge oligocène supérieur et de sa répartition biogéographique. Il s’agit d’un nucule de Boraginaceae désormais nommé Boraginocarpus fallax (Taugourdeau-Lantz & Rosset 1966) comb. nov.AbstractA re-analysis and new description of the incertae sedis Calcicarpinum? fallax is presented, and its Late Oligocene age and paleobiogeographical distribution is ascertained. It is identified as a nutlet of a Boraginaceae and is named Boraginocarpus fallax (Taugourdeau-Lantz & Rosset 1966) comb. nov.

Neubenennungen lithostratigraphischer Einheiten in der Helvetischen Kreide

In September 2007 Föllmi and coauthors requested the approval of four lithostratigraphic terms of the Swiss Committee of Stratigraphy (SCS). These terms were to be used in their publication on the Cretaceous in the Helvetic realm (Föllmi et al. 2007). At its meeting on October 18, 2007, the SCS decided the following: The Tierwis Formation (replacing the Drusberg Formation) was accepted, with the reserve that a section at Tierwis should be published in the near future. For the former “Lower Orbitolina Beds” the term Rawil Member was accepted, but here too a better type section than the one at Rawil Pass should be published. The term Rohrbachstein bed should not be used as a formal unit because it describes only a minor lithologic variation within the Grünten Member. The term Plaine Morte bed for a thin condensed horizon can not be accepted due to the fact that its definition is based mainly on biostratigraphy. Furthermore, the duplication a locality term which is in use for a previously established lithostratigraphic unit should be avoided.RésuméEn septembre 2007, Föllmi et coauteurs ont demandé l’approbation du Comité suisse de Stratigraphie (CSS) pour quatre noms d’unités lithostratigraphiques, en vue d’une publication sur le Crétacé de l’Helvétique (Föllmi et al. 2007). Lors de sa séance du 18 octobre 2007, le CSS a pris les décisions suivantes: La Formation de Tierwis est acceptée en remplacement de la Formation du Drusberg, mais avec le souhait qu’une coupe dans la région de Tierwis soit publiée prochainement. Le terme de Membre du Rawil est également accepté pour les anciennes « Couches à Orbitolines inférieures », avec la demande qu’une meilleure coupe-type que celle du col du Rawil soit publiée. Le terme Banc de Rohrbachstein ne devrait pas être utilisé comme unité formelle, parce qu’il ne décrit qu’une variation lithologique mineure au sein du Membre de Grünten. Le Banc de la Plaine Morte est refusé car il ne remplit pas les critères de définition d’une unité lithostratigraphique. En outre, le toponyme « Plaine Morte » est déjà utilisé (Wildflysch Plaine Morte).