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[dinosaur] Archosauromorph teeth from Triassic of Spain + Lutemys, turtle from Cretaceous of Utah + Dracaenosaurus + Clevosaurus




Ben Creisler
bcreisler@gmail.com


Some recent non-dino papers (some with free pdfs):


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This one is not yet officially posted but the pdf is available....


MartÃn D. Ezcurra, Josep Fortuny, Eudald Mujal, and Arnau Bolet (2017)
First direct archosauromorph remains from the Early-Middle Triassic transition of the Iberian Peninsula.
Palaeontologia Electronica 20.3.62A: 1-10.
doi: https://doi.org/10.26879/686

This link is not yet active...
http://palaeo-electronica.org/content/2017/1855-archosauromorphs-from-spain

The pdf can be downloaded here:

http://palaeo-electronica.org/content/pdfs/686.pdf

This paper discusses the taxonomic affinities of three isolated teeth discovered in the Buntsandstein facies of the Catalan Coastal ranges and central-eastern Pyrenean basins that crop out in Catalonia, north-eastern Spain. The tooth crowns are blade-like, labiolingually compressed, distally recurved, and proportionally apicobasally tall, in which the most complete of them is at least 2.4 times taller than its mesiodistal depth at base. The distal margins possess a densely serrated carina, and the mesial margins lack carina and serrations. The enamel of the crowns lacks ornamentation (e.g., wrinkles, ridges) or macroscopic wear-facets. The three teeth are referred to indeterminate crocopodan archosauromorphs based on the presence of labiolingually compressed and serrated crowns. The absence of mesial denticles resembles the condition in the non-archosauriform archosauromorph Teyujagua, proterosuchids, and some more crownward archosauriforms (e.g., some proterochampsids). We could not find evidence to determine if these teeth belong to a single or multiple closely related species. These remains represent the first direct archosauromorph remains from LowerâMiddle Triassic beds of the Iberian Peninsula and add information about the geographic distribution of the group during the dawn of the evolutionary radiation of the group.ÂÂ


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Lutemys warreni, gen. et sp. nov.r

Tyler R. Lyson, Walter G. Joyce & Joseph J. W. Sertich (2017)
A new chelydroid turtle, Lutemys warreni, gen. et sp. nov., from the Upper Cretaceous (Campanian) Kaiparowits Formation of southern Utah.Â
Journal of Vertebrate Paleontology Article: e1390672 (advance online publication)Â
DOI: 10.1080/02724634.2017.1390672.
http://www.tandfonline.com/doi/full/10.1080/02724634.2017.1390672

A fragmentary skeleton from the Kaiparowits Formation (Upper Campanian) of southern Utah represents a new taxon of chelydroid turtle herein named Lutemys warreni. Lutemys warreni differs from other chelydroids in the presence of a smooth shell, lack of plastral or carapacial fontanelles, and development of a thin, gracile plastron. A maximum parsimony analysis of all Late Cretaceous and early Paleogene chelydroids from Laramidia suggests that L. warreni is the most basal known stem kinosternoid. Lutemys warreni therefore represents the fourth named pan-kinosternoid from the Late Cretaceous western island landmass of Laramidia and the first named pan-kinosternoid from the Kaiparowits Formation. The description of L. warreni increases the taxonomic diversity of the Kaiparowits Formation to 16 turtle taxa, making it one of the most diverse fossil turtle assemblages.

http://zoobank.org/urn:lsid:zoobank.org:pub:C199E9AE-6F3C-442A-AA12-3960B28F4066

SUPPLEMENTAL DATAâSupplemental materials are available for this article for free at www.tandfonline.com/UJVP

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Andrej ÄerÅanskÃ, Arnau Bolet, Johannes MÃller, Jean-Claude Rage, Marc Augà & Anthony Herrel (2017)
A new exceptionally preserved specimen of Dracaenosaurus (Squamata, Lacertidae) from the Oligocene of France as revealed by micro-computed tomography.Â
Journal of Vertebrate Paleontology Article: e1384738 (advacne online publication)
DOI: 10.1080/02724634.2017.1384738.
http://www.tandfonline.com/doi/full/10.1080/02724634.2017.1384738


The best-preserved material of Dracaenosaurus croizeti, an almost complete and previously unpublished skull with a few associated postcranial bones (stylopodium, zeugopodium, and cervical vertebra), is described. The material comes from the locality of Cournon, a late Oligocene site in south-central France. Micro-computed tomography applied to this specimen revealed previously unknown internal osteological characters. Among lacertids, this taxon represents a notable phenomenon: it is an extreme durophagous specialist. Many of the newly observed cranial character states reflect the lifestyle of this lizard, because animals with a hard-shelled diet display a specialized cranial morphology associated with more massive cranial muscles. One unique character for Lacertidae is observed: the parietal-supraoccipital contact is formed by a ventrally deep parietal crest that fits into a bifurcate ascending process of the supraoccipital. In fact, such a connection represents the opposite to the connection in modern members of Lacertidae. Phylogenetic analysis recovered Dracaenosaurus inside Gallotiinae, a clade that would consist of the mainly Oligocene genera Pseudeumeces and Dracaenosaurus, the Miocene genus Janosikia, and the extant Psammodromus and Gallotia. Our study supports previous phylogenetic results and provides an example of the achievement of large size in mainland members of the stem of Gallotia, previously exemplified by Janosikia and Pseudeumeces. The extreme amblyodonty of Dracaenosaurus also confirms the view that herbivory in Gallotia is derived and may be the result of insularity.

SUPPLEMENTAL DATAâSupplemental materials are available for this article for free at www.tandfonline.com/UJVP




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Free pdf:



Aileen OâBrien, David I. Whiteside & John E. A. Marshall (2017)
Anatomical study of two previously undescribed specimens of Clevosaurus hudsoni (Lepidosauria: Rhynchocephalia) from Cromhall Quarry, UK, aided by computed tomography, yields additional information on the skeleton and hitherto undescribed bones.
Zoological Journal of the Linnean Society, zlx087 (advance online publication)
doi: https://doi.org/10.1093/zoolinnean/zlx087
https://academic.oup.com/zoolinnean/advance-article/doi/10.1093/zoolinnean/zlx087/4744334


We investigate two well-preserved and previously undescribed specimens of Clevosaurus hudsoni from a Late Triassic fissure deposit at Cromhall Quarry, SW Britain. For the first time computed tomography (CT) scans of British Triassic fissure specimens have been successfully digitally segmented. Visualisation software was used to isolate bone from matrix and to separate individual bones from each other, revealing hidden cranial and postcranial elements. The CT data, together with stereoscopic microscope analysis, have enabled a full evaluation of the specimens including previously poorly known or undescribed elements of the type species of the clevosaur clade. We present detailed descriptions of the cervical vertebrae including the atlas-axis complex. Little studied bones such as the gastralia and epipodials are detailed here and a gap in the lower temporal bar is confirmed. Sclerotic ossicles are presented for the first time for C. hudsoni. A fully fused scapulocoracoid and unfused astragalus and calcaneum provide new insights into clevosaur ontogeny. The CT scans provide key information on post mortem movement and taphonomy of the specimen, revealing fragmentation of part of the skull by the right arm, which has been thrust into the right side of the skull displacing both cranial and jaw bones.



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