Field of Science

Numerous Triassic Presentation Abstracts from the Fourth Latinamerican Congress of Vertebrate Paleontology

A new issue of the South American journal Ameghiniana includes (starting on page 32) the set of published abstracts from the IV Congreso Latinamericano  de Paleontologia Vertebrados, which was held in San Juan Argentina in September of 2011.  There are numerous Triassic themed abstracts in here as there were sessions of basal archosaurs, early theropods, therapsids, as well as geological sessions. I gave two talks at the meeting, one on newly discovered cranial material of Poposaurus gracilis; the other on the stratigraphic position of the Placerias Quarry of Arizona, which contains the earliest known neotheropod dinosaur. A volume is currently in press containing many of the papers from the basl archosaurs session.

You can download the published abstract volume here:

http://www.ameghiniana.org.ar/index.php/ameghiniana

Once the page loads, click on the small text "PDF" in the lower right corner.

Footprints of Large Theropod Dinosaurs from the Late Triassic of Brazil

The Caturrita Formation may be younger than previously thought and there is a currently undiscovered large theropod in the latest Triassic of Brazil.

da Silva, R. C., Barboni, R., Dutra, T., Godoy, M. M., and R. B. Binotto. 2012. Footprints of large theropod dinosaurs and implications on the age of Triassic biotas from southern Brazil. Journal of South American Earth Sciences 39:16-23. http://dx.doi.org/10.1016/j.jsames.2012.06.017

Abstract - Dinosaur footprints found in an outcrop of the Caturrita Formation (Rio Grande do Sul State, Southern Brazil), associated with a diverse and well preserved record of fauna and flora, reopen the debate about its exclusive Triassic age. The studied footprints were identified as Eubrontes isp. and are interpreted as having been produced by large theropod dinosaurs. The morphological characteristics and dimensions of the footprints are more derived than those commonly found in the Carnian–Norian, and are more consistent with those found during the Rhaetian–Jurassic. The trackmaker does not correspond to any type of dinosaur yet known from Triassic rocks of Brazil. Recent studies with the paleofloristic content of this unit also support a more advanced Rhaetian or even Jurassic age for this unit.


A New Ctenosauriscid from Eastern Europe, Bystrowisuchus flerovi May Represent the Oldest Known Crown-Group Archosaur


This paper describes a new ctenosauriscid archosaur from the Early Triassic of EuropeBystrowisuchus flerovi is based upon a series of fragmentary cervical vertebrae and a partial right ilium. It differs from other ctenosauriscids in the presence of expanded spine tables on the apices of the neural spines, and by possessing generally shorter neural spines. Based on these characters Sennikov considers Bystrowisuchus to be transitional between rauisuchids and ctenosauriscids. Note that Sennikov prefers to use traditional Linnaean systematics rather than cladistics (and still recognizes Thecodontia as a taxonomic entity). A new family Lotosauridae is erected and considered distinct from other ctenosauriscids [Ctenosauriscidae]. The type locality is dated latest Olenekian, which means that Bystrowisuchus  is probably older than Xilousuchus which is ambiguously from the latest Olenekian-early Anisian of China and therefore could represent the oldest record of a ctenosauriscid and crown-group archosaur.

Sennikov, A. G. 2012. The first ctenosauriscid (Reptilia: Archosauromorpha) from the Lower Triassic of Eastern Europe. Paleontological Journal [Paleontologicheskii Zhurnal] 46:499-511.

Abstract - A new Early Triassic thecodont from the Donskaya Luka locality is described. A new species and genus of Rauisuchidae, Bystrowisuchus flerovi gen. et sp. nov., the first East European and earliest known member of the family Ctenosauriscidae is established. The taxonomy and phylogeny of Rauisuchidae and their stratigraphical and geographical distribution in connection with new finds are discussed.

A New Turtle Dominated Fossil Biota from the Late Triassic (Norian) of Poland


This paper documents a newly discovered fauna from the Norian of Poland that is important because it is dominated by fossils of what is most likely a new taxon of turtle. Of course Late Triassic terrestrial turtles are very rare so we will watch further research from this site with interest. The locality also includes other vertebrate taxa including a coelophysoid dinosaur and an aetosaur.  The aetosaur is of interest because the dorsal vertebra possesses a distinct hyposphene, a character previously only found in Desmatosuchus from North America and Aetobarbakinoides from Brazil.  This new site is also significant because it preserves micro and macrofloral fossils, which are generally uncommonly associated with vertebrate remains. Large temnospondyls are also rare in the Norian, but this site has one as well.

Sulej, T., Niedźwiedzki, G., and R. Bronowicz. 2012. A new Late Triassic vertebrate fauna from Poland with turtles, aetosaurs, and coelophysoid dinosaurs. Journal of Vertebrate Paleontology 23: 1033-1041. DOI:10.1080/02724634.2012.694384

Abstract - We report a new site with an occurrence of isolated bones of a Palaeochersis-like turtle in Norian-Rhaetian fluvial sediments from southern Poland. The turtle remains are associated with bones of a medium-sized aetosaur, a coelophysoid dinosaur, and a larger carnivorous archosaur, as well as a hybodontid shark, ganoid and dipnoan fishes, and a large temnospondyl.