[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

[dinosaur] Fraxinisaura, new lepidosauromorph from Middle Triassic of Germany + placodonts from Spain





Ben Creisler
bcreisler@gmail.com


New non-dino papers:


Fraxinisaura rozynekae gen. & sp. nov.



Rainer R. Schoch & Hans-Dieter Sues (2018)
A new lepidosauromorph reptile from the Middle Triassic (Ladinian) of Germany and its phylogenetic relationships.
Journal of Vertebrate Paleontology Article: e1444619
DOI: 10.1080/02724634.2018.1444619
https://www.tandfonline.com/doi/full/10.1080/02724634.2018.1444619



Although lepidosaurs are by far the most diverse and widespread group of present-day nonavian reptiles, with over 10,000 formally named species, their early diversification is documented only by a handful of incomplete fossils with few diagnostic features. Recent excavations in strata of the Lower Keuper (Middle Triassic: Ladinian) of Baden-WÃrttemberg, Germany, have yielded abundant skeletal remains of a diversity of small- to medium-sized diapsid reptiles, which include at least three taxa of lepidosauromorphs. One, here named Fraxinisaura rozynekae, is a small-bodied reptile characterized by (1) maxillary and dentary tooth crowns conical, with lingual striae near their apices; (2) maxilla with a dorsoventrally low facial process and long tooth-bearing portion anterior to this process; (3) jugal with a short anterior process and a very short, pointed posterior process; and (4) ilium with a tall, posterodorsally extending blade. Tooth implantation is pleurodont. Size variation in the sample sheds some light on ontogenetic changes, mainly affecting the shape of and ornamentation on cranial bones. Phylogenetic analysis recovered Fraxinisaura rozynekae among Lepidosauromorpha and as the sister taxon of the Middle to Late Jurassic Marmoretta oxoniensis. Unfortunately, currently existing character-taxon matrices do not allow confident resolution of the interrelationships of these and other early Mesozoic lepidosauromorph reptiles.

http://zoobank.org/urn:lsid:zoobank.org:pub:02C69A1C-FCC8-4D0C-BA71-79BA30BC9DA7

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


News:

with skull illustration

https://www.paleowire.com/just-out-a-new-lepidosauromorph-reptile-from-the-middle-triassic-ladinian-of-germany-and-its-phylogenetic-relationships-journal-of-vertebrate-paleontology/




=========





Carlos de Miguel Chaves, Torsten M. Scheyer Francisco Ortega & AdÃn PÃrez-GarcÃa (2018)
The placodonts (Sauropterygia) from the Middle Triassic of Canales de Molina (Central Spain), and an update on the knowledge about this clade in the Iberian record.
Historical Biology (advance online publication)
doi:Â https://doi.org/10.1080/08912963.2018.1462805Â Â
https://www.tandfonline.com/doi/full/10.1080/08912963.2018.1462805


The Iberian fossil record of placodonts, a group of Triassic marine reptiles with specialized crushing trophic adaptations, is mostly based on scarce isolated remains and therefore poorly informative. Abundant placodont remains were found in the 1980âs in Middle Triassic levels (Ladinian, Muschelkalk Facies) of Canales de Molina (Guadalajara Province, Central Spain), but they remained unpublished. This material is described and figured here for the first time. It includes isolated teeth and armor plates, but also the first relatively complete placodont carapace found in the Iberian record. Paleohistological studies performed here on several isolated armor plates of different sizes suggest that all of them could belong to different ontogenetic stages of the same taxon, the carapace probably representing a juvenile individual of a potential new species within the genus Psephosauriscus. This is the first reference of this genus in the European record, being so far known from the Middle Triassic of the Middle East. An update considering all so far published Iberian specimens of Placodontia is performed.

===