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[dinosaur] German mosasaurid and plesiosaurian remains + Confuciusornis bone oxygen isotopes + lizards




Ben Creisler
bcreisler@gmail.com


Some recent non-dino papers:


Sven Sachs, Jahn J. Hornung & Udo Scheer (2017) 
Mosasaurid and plesiosaurian remains from marginal facies of the lower Campanian (Upper Cretaceous) Bottrop and Vaals formations of western Germany.
Cretaceous Research (advance online publication)
doi: https://doi.org/10.1016/j.cretres.2017.05.026
http://www.sciencedirect.com/science/article/pii/S0195667116304220


Isolated remains of mosasaurids and plesiosaurians are recorded from the lower Campanian Bottrop and Vaals formations of North Rhine-Westphalia, western Germany. A tooth crown from Bottrop-Fuhlenbrock, referred to an elasmosaurid plesiosaurian, represents the first record of this group from late-Upper Cretaceous strata of the area. Another presumed plesiosaurian remain is a fragmentary gastralium from Duisburg-Walsum. Some of the mosasaurid material from the Bottrop Formation (a tooth crown and vertebrae from Bottrop-Fuhlenbrock and Duisburg-Walsum) is assigned to the subfamily Plioplatecarpinae. The Vaals Formation, which is a lateral equivalent of the Bottrop Formation, yielded a single tooth crown, found at Aachen-Bildchen, that is here referred to the genus Hainosaurus. These finds from the Bottrop and Vaals formations constitute evidence of the presence of these taxa in proximal shelf to nearshore settings during the Campanian. The mosasaurid occurrences in particular may be an indicator that diversity and abundance increased in more basinward facies and greater palaeowaterdepth.


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Romain Amiot, Delphine Angst, Serge Legendre, Eric Buffetaut, François Fourel, Jan Adolfssen, Aurore André, Ana Voica Bojar, Aurore Canoville, Abel Barral, Jean Goedert, Stanislaw Halas, Nao Kusuhashi, Ekaterina Pestchevitskaya, Kevin Rey, Aurélien Royer, Antônio Álamo Feitosa Saraiva, Bérengère Savary-Sismondini, Jean-Luc Siméon, Alexandra Touzeau, Zhonghe Zhou & Christophe Lécuyer (2017)
Oxygen isotope fractionation between bird bone phosphate and drinking water.
The Science in Nature (advance online publication)
DOI: 10.1007/s00114-017-1468-2
https://link.springer.com/article/10.1007/s00114-017-1468-2


Oxygen isotope compositions of bone phosphate (δ18Op) were measured in broiler chickens reared in 21 farms worldwide characterized by contrasted latitudes and local climates. These sedentary birds were raised during an approximately 3 to 4-month period, and local precipitation was the ultimate source of their drinking water. This sampling strategy allowed the relationship to be determined between the bone phosphate δ18Op values (from 9.8 to 22.5‰ V-SMOW) and the local rainfall δ18Ow values estimated from nearby IAEA/WMO stations (from −16.0 to −1.0‰ V-SMOW). Linear least square fitting of data provided the following isotopic fractionation equation: δ18Ow = 1.119 (±0.040) δ18Op − 24.222 (±0.644); R2 = 0.98. The δ18Op–δ18Ow couples of five extant mallard ducks, a common buzzard, a European herring gull, a common ostrich, and a greater rhea fall within the predicted range of the equation, indicating that the relationship established for extant chickens can also be applied to birds of various ecologies and body masses. Applied to published oxygen isotope compositions of Miocene and Pliocene penguins from Peru, this new equation computes estimates of local seawater similar to those previously calculated. Applied to the basal bird Confuciusornis from the Early Cretaceous of Northeastern China, our equation gives a slightly higher δ18Ow value compared to the previously estimated one, possibly as a result of lower body temperature. These data indicate that caution should be exercised when the relationship estimated for modern birds is applied to their basal counterparts that likely had a metabolism intermediate between that of their theropod dinosaur ancestors and that of advanced ornithurines.


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Stefanikia siderea gen. et sp. nov.,

Andrej Čerňanský & Krister T. Smith (2017)

Eolacertidae: a new extinct clade of lizards from the Palaeogene; with comments on the origin of the dominant European reptile group – Lacertidae.

Historical Biology ( advance online publication)

doi:  http://dx.doi.org/10.1080/08912963.2017.1327530  

http://www.tandfonline.com/doi/full/10.1080/08912963.2017.1327530

 



We describe a new lizard taxon, Stefanikia siderea gen. et sp. nov., from the early-middle Eocene locality of Messel in Germany based on a nearly complete skeleton, which we studied using μCT methods. It shares many characters with the Eocene taxon Eolacerta, which is broadly distributed in the Eocene of central and Western Europe, but is much smaller and shows several important anatomical differences. The new discovery sheds light on the paleodiversity of these lizards in the Eocene of Europe, and the new family name Eolacertidae is proposed to encompass Eolacerta and Stefanikia. The relationships of Eolacerta have been intractable. Our phylogenetic analyses confirm that Eolacertidae is a member of the clade Lacertiformes and provide strong support for a sister-group relationship to Lacertidae. In some places, skin impressions are preserved, displaying the body scalation. As such, the exquisitely preserved specimens of Eolacertidae from Messel provide new insight into the morphology and ecology of lizards on the stem of Lacertidae, Europe’s dominant group of living reptiles.

 

http://zoobank.org/urn:lsid:zoobank.org:pub:DFD01563-A913-4286-B64B-E0912474FD08


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Krister T. Smith (2017)
First crocodile-tailed lizard (Squamata: Pan-Shinisaurus) from the Paleogene of Europe.
Journal of Vertebrate Paleontology Article: e1313743
DOI: 10.1080/02724634.2017.1313743
http://www.tandfonline.com/doi/full/10.1080/02724634.2017.1313743
 
Crocodile-tailed lizards are represented by a single extant species, Shinisaurus crocodilurus, the Chinese crocodile lizard, which until 2006 was completely unknown in the fossil record. These lizards may play an important role in understanding squamate phylogeny, but their biogeographic history remains murky. A new specimen from the middle Eocene of Messel, Germany, is the first record of the clade in the Paleogene of Europe. The specimen comprises an autotomized tail preserved in complete articulation. It retains a number of plesiomorphies with respect to S. crocodilurus, and it also differs from the coeval species Bahndwivici ammoskius, but comparisons with other shinisaurs are necessarily limited. The present specimen documents for the first time in the fossil record the superficially crocodile-like tail for which the extant species is named, indicating aquatic adaptation already by the middle Eocene. It furthermore raises questions about the identification of isolated ‘necrosaur’ material from the European Paleogene. Finally, it adds to growing evidence of a taxonomically similar squamate fauna in Europe and North America in the early Paleogene.

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