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Université de Fribourg

A new species of baenid turtle from the Early Cretaceous Lakota Formation of South Dakota

Joyce, Walter G. ; Rollot, Yann ; Cifelli, Richard L.

In: Fossil Record, 2020, vol. 23, no. 1, p. 1–13

Baenidae is a clade of paracryptodiran turtles known from the late Early Cretaceous to Eocene of North America. The proposed sister-group relationship of Baenidae to Pleurosternidae, a group of turtles known from sediments dated as early as the Late Jurassic, suggests a ghost lineage that crosses the early Early Cretaceous. We here document a new species of paracryptodiran turtle, Lakotemys...

Université de Fribourg

Petrophysical joint inversion applied to alpine permafrost field sites to image subsurface ice, water, air, and rock contents

Mollaret, Coline ; Wagner, Florian M. ; Hilbich, Christin ; Scapozza, Cristian ; Hauck, Christian

In: Frontiers in Earth Sc-ience, 2020, vol. 8, p. -

Quantification of ground ice is crucial for understanding permafrost systems and modeling their ongoing degradation. The volumetric ice content is however rarely estimated in permafrost studies, as it is particularly difficult to retrieve. Standard borehole temperature monitoring is unable to provide any ice content estimation, whereas non-invasive geophysical techniques, such as refraction ...

Université de Fribourg

First fossil frog from Antarctica: implications for Eocene high latitude climate conditions and Gondwanan cosmopolitanism of Australobatrachia

Mörs, Thomas ; Reguero, Marcelo ; Vasilyan, Davit

In: Scientific Reports, 2020, vol. 10, p. 5051

Cenozoic ectothermic continental tetrapods (amphibians and reptiles) have not been documented previously from Antarctica, in contrast to all other continents. Here we report a fossil ilium and an ornamented skull bone that can be attributed to the Recent, South American, anuran family Calyptocephalellidae or helmeted frogs, representing the first modern amphibian found in Antarctica. The two bone...

Université de Fribourg

A reevaluation of the basal turtle Indochelys spatulata from the Early–Middle Jurassic (Toarcian–Aalenian) of India, with descriptions of new material

Joyce, Walter G. ; Bandyopadhyay, Saswati

In: PeerJ, 2020, vol. 8, p. e8542

Background Indochelys spatulata is an extinct turtle from the Early to Middle Jurassic Kota Formation of the Pranhita–Godavari Gondwana basin, India. The holotype and previously only known specimen is a partially eroded shell that had been collected near Kota village, north of Sironcha, in Maharashtra State. Phylogenetic analyses have consistently suggested placement at the base of the...

Université de Fribourg

Notes on the cheek region of the Late Jurassic theropod dinosaur Allosaurus

Evers, Serjoscha W. ; Foth, Christian ; Rauhut, Oliver W.M.

In: PeerJ, 2020, vol. 8, p. e8493

Allosaurus, from the Late Jurassic of North America and Europe, is a model taxon for Jurassic basal tetanuran theropod dinosaurs. It has achieved an almost iconic status due to its early discovery in the late, 19th century, and due to the abundance of material from the Morrison Formation of the western U.S.A., making Allosaurus one of the best-known theropod taxa. Despite this, various...

Université de Fribourg

Late Jurassic theropod dinosaur bones from the Langenberg Quarry (Lower Saxony, Germany) provide evidence for several theropod lineages in the central European archipelago

Evers, Serjoscha W. ; Wings, Oliver

In: PeerJ, 2020, vol. 8, p. e8437

Marine limestones and marls in the Langenberg Quarry provide unique insights into a Late Jurassic island ecosystem in central Europe. The beds yield a varied assemblage of terrestrial vertebrates including extremely rare bones of theropod from theropod dinosaurs, which we describe here for the first time. All of the theropod bones belong to relatively small individuals but represent a wide...

Université de Fribourg

The fossil record of the genus Varanus from the Southern Caucasus (Armenia, Georgia)

Vasilyan, Davit ; Bukhsianidze, Maia

In: PeerJ, 2020, p. e8322

The Southern Caucasus, with its special geographic position and complex topography, is a well-known biodiversity hotspot. However, the formation of this hotspot remains largely unstudied. To reveal this, a thorough study of the fossil record of the region is necessary. In the present paper, we describe for the first time fossil monitor lizards (Varanus sp.) from two late Miocene localities from...

Université de Fribourg

A review of the fossil record of nonbaenid turtles of the clade Paracryptodira

Joyce, Walter G. ; Anquetin, Jérémy

In: Bulletin of the Peabody Museum of Natural History, 2019, vol. 60, no. 2, p. 129–155

The fossil record of nonbaenid paracryptodires ranges from the Late Jurassic (Kimmeridgian) to the Paleocene of North America and Europe only. Earlier remains may be present as early as the Middle Jurassic (Bathonian). Only a single dispersal event is documented between the two continents after their breakup during the Cretaceous in the form of the appearance of the Compsemys lineage in the ...

Université de Fribourg

Ice-penetrating radar survey of the subsurface debris field at Camp Century, Greenland

Karlsson, Nanna B. ; Colgan, William T. ; Binder, Daniel ; Machguth, Horst ; Abermann, Jakob ; Hansen, Karina ; Pedersen, Allan Ø.

In: Cold Regions Science and Technology, 2019, vol. 165, p. 102788

The warming climate is changing the surface dynamics of the Greenland Ice Sheet, including the balance between snowfall and melt. Increasing surface melt impacts the structure of the relatively porous near-surface layer known as firn. Camp Century, a base abandoned in 1967, now comprises a subsurface debris field within the firn in Northwest Greenland. We collected 80 km of 100 or 250 MHz...

Université de Fribourg

A non-archaeopterygid avialan theropod from the Late Jurassic of southern Germany

Rauhut, Oliver W. M. ; Tischlinger, Helmut ; Foth, Christian

In: eLife, 2019, vol. 8, p. e43789

The Late Jurassic ‘Solnhofen Limestones’ are famous for their exceptionally preserved fossils, including the urvogel Archaeopteryx, which has played a pivotal role in the discussion of bird origins. Here we describe a new, non-archaeopterygid avialan from the Lower Tithonian Mörnsheim Formation of the Solnhofen Archipelago, Alcmonavis poeschli gen. et sp. nov. Represented by a right...