[dinosaur] Eocene penguin cranium from Antarctica + elasmosaur from Germany + Triassic turtle tracks

Ben Creisler

bcreisler@gmail.com

Some recent non-dino papers:

(I don't have access so I don't know if there is a new taxon named.)

Nadia Haidr & Carolina Acosta Hospitaleche (2017)

A new penguin cranium from Antarctica and its implications for body size diversity during the Eocene.

Neues Jahrbuch fÃr Geologie und PalÃontologie - Abhandlungen 286(2):. 229-233

DOI: https://doi.org/10.1127/njgpa/2017/0698

http://www.ingentaconnect.com/content/schweiz/njbgeol/2017/00000286/00000002/art00008

Although penguins have a very abundant fossil record in Antarctica, very few cranial elements have been found so far, and in all the cases the specimens are incomplete. We describe a new cranium of a medium-sized penguin from the late Eocene Submeseta Formation in Marambio/ Seymour Island, Antarctica. Its morphology allows us to establish a common cranial pattern for all known Eocene taxa (including South American, Antarctic and probably Oceanian species), with very different proportions between cranium and post-cranium from those of modern penguins. These Paleogene fossils exhibit a small neurocrania, extremely elongated bills, large occipital condyles, and strong cranio-mandibular articulations.

Nadia S. Haidr & Carolina Acosta Hospitaleche (2017)

New data on the humerotriceps of penguins and its implications in the evolution of the fossa tricipitalis.

Historical Biology (advance online publication)

doi:Â http://dx.doi.org/10.1080/08912963.2017.1396324ÂÂ

Âhttp://www.tandfonline.com/doi/full/10.1080/08912963.2017.1396324

A paddle-shaped wing, the general morphology of the humerus, and the muscles involved in wing movement are among the most characteristic adaptations to diving in penguins. Particularly, the humeral fossa tricipitalis and the musculus humerotriceps are clear examples of muscular rearrangement accompanying skeletal changes. In extant Spheniscidae, we were able to identify two heads of this muscle attaching within a different compartment of the bipartite fossa. Since the partition of the fossa appeared as a novelty during the Miocene, we propose that this might have had implications for underwater flight contributing to wing-propelled diving efficiency.

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The pdf is free at link, not yet posted on the journal open access website.

(in German)

S. Sachs & J. Ladwig. (2017)

Reste eines Elasmosauriers aus der Oberkreide von Schleswig-Holstein in der Sammlung des Naturkunde-Museums Bielefeld. [Remains of an elasmosaur from the Upper Cretaceous ofÂSchleswig-Holstein in the collection of the Natural HIstory Museum Bielefeld]

Berichte Naturwissenschaftlicher Verein fÃr Bielefeld und Umgegend 55: 28-36

https://drive.google.com/open?id=1fiJHJducuSdH3Z_R1pAW2Bq0yUMIW5is

In 2016, the Natural History Museum Bielefeld received fragmentary remains of an elasmosaurid plesiosaurian from the upper Campanian of Kronsmoor (Steinburg district) in Schleswig-Holstein (northern Germany). The material includes incomplete vertebrae, phalanges and unidentifiable fragments. Additional parts of the same skeleton (a tooth, cervical-, dorsal- and caudal vertebrae, limb elements and 110 gastroliths) are housed at the Institute for Geology of the University of Hamburg and in private collections.

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MatÃas Reolid, Ana MÃrquez-Aliaga, Margarita BelinchÃn, Anna GarcÃa-Forner, JosÃ Villena & Carlos MartÃnez-PÃrez (2017)

Ichnological evidence of semi-aquatic locomotion in early turtles from eastern Iberia during the Carnian Humid Episode (Late Triassic).

Palaeogeography, Palaeoclimatology, Palaeoecology (advance online publication)

doi: https://doi.org/10.1016/j.palaeo.2017.11.025

http://www.sciencedirect.com/science/article/pii/S0031018217306843

Highlights

Early European record of fossil turtle footprints, Middle Carnian

Fluvial sandstones with tridactyl and tetradactyl digit imprints and scratch marks

Scratches produced by buoyant tetrapod that swam in very shallow environment

Abundance of turtle footprints in the Middle Carnian sandstones of eastern Iberia

Carnian Humid Episode favoured diversification of early turtles in fresh water environments

Abstract

Some of the earliest European records of fossil turtle footprints (Late Triassic, Middle Carnian, ~ 227â237 Ma) are interpreted from 46 footprints from three outcrops, DomeÃo, Quesa and Cortes de Pallas, located in the Iberian Range (eastern Spain). The samples were obtained from Upper Triassic rocks in Keuper Facies. They are characterized in the studied area by two well-defined evaporitic sequences, separated by a detrital stratigraphic interval, constituting the Manuel Sandstones Formation in which the studied fossil footprints were recorded. These fluvial deposits are correlatable with the Carnian Humid Episode. The footprints are tridactyl and tetradactyl, mainly digitigrade, and elongated scratch marks are common. The digit traces present triangular and curved claws. The morphology of these marks suggests they were produced by the autopodium of a tetrapod animal while swimming near the bottom, and they are consistent with the anatomical features of a turtle's manus. Other footprints were produced by turtles walking in wet medium- to coarse-grained sand in a subaerial environment. A short trackway is identified, sharing similarities with both the ichnogenera Emydhipus and Chelonipus. The observed tracks support a freshwater semi-aquatic habit for some stem turtles during the early Late Triassic. These are remarkably ancient turtle tracks, close to the origin of the group, as indicated by skeletal fossils; they confirm that the earliest forms were narrowly related to aquatic (fluvial) environments.

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