Cynodont therapsids diversified extensively after the Permo-Triassic mass extinction event, and gave rise to mammals in the Jurassic. We use an enlarged and revised dataset of discrete skeletal characters to build a new phylogeny for all main cynodont clades from the Late Permian to the Early Jurassic, and we analyse models of morphological diversification in the group. Basal taxa and epicynodo...

The South African species Euparkeria capensis is of great importance for understanding the early radiation of archosauromorphs (including archosaurs) following the Permo-Triassic mass extinction, as most phylogenetic analyses place it as the sister taxon to crown group Archosauria within the clade Archosauriformes. Although a number of species from Lower-Middle Triassic deposits worldwide have ...

BACKGROUND Modern selachians and their supposed sister group (hybodont sharks) have a long and successful evolutionary history. Yet, although selachian remains are considered relatively common in the fossil record in comparison with other marine vertebrates, little is known about the quality of their fossil record. Similarly, only a few works based on specific time intervals have attempted to i...

Sun et al. (Reports, 19 October 2012, p. 366) reconstructed Permian to Middle Triassic equatorial seawater temperatures. After correct temporal positioning of their data points, their presumed trends of temperature changes, and hence their assumption of a one-to-one relationship between putative "lethally hot" seawater temperatures and a disputable equatorial "eclipse" of some organisms, are no...

BACKGROUND Sauropterygia is an abundant and successful group of Triassic marine reptiles. Phylogenetic relationships of Triassic Sauropterygia have always been unstable and recently questioned. Although specimens occur in high numbers, the main problems are rareness of diagnostic material from the Germanic Basin and uniformity of postcranial morphology of eosauropterygians. In the current paper...

Unspecified DOI: 10.1111/j.1751-8369.1990.tb00382.x Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: http://doi.org/10.5167/uzh-112675 Originally published at: Mørk, Atle; Vigran, Jorunn Os; Hochuli, Peter A (1990). Geology and palynology of the Triassic succession of Bjørnøya. Polar Research, 8(2):141-163. DOI: 10.1111/j.1751-8369.1990.tb00382.x Geology and paly...

Carbon isotopic studies from marine organic matter of the Permian-Triassic Maitai Group, New Zealand, reveal a significant 5Corg shift toward more negative values within the Little Ben Sandstone Formation. These isotopic data chemostratigraphically define the previously debated position of the Permian-Triassic boundary in the Maitai Group. The Permian-Triassic record of the Maitai Group is also...

A total of 17 sphene and 45 zircon fission track ages (FTA) are reported from the Piedmont Province of Pennsylvania, Delaware, and Maryland, the Reading Prong of New Jersey, and the Newark Basin of Pennsylvania. With the exception of one sphene sample, FTA fall within a relatively restricted age range: sphene 190-217 Ma (average 199 Ma) and zircon 143-218 Ma (average 184 Ma). Near concordance o...

Conulariids are unusual extinct metazoans most often considered to be a group of scyphozoan cnidarians or close relatives. Generally, the temporal range of conulariid fossils is perceived to be late Precambrian or Cambrian to Triassic, though a supposed Cretaceous conulariid from Peru was published 46 years ago. A re-evaluation of this fossil indicates it is not a conulariid, but instead a pinn...

The 'Rauisuchia' are a group of Triassic pseudosuchian archosaurs that displayed a near worldwide distribution. In Brazil, their fossils are found only in the Santa Maria Formation (Paraná Basin) of the Rio Grande do Sul State, specifically in the Middle Triassic Dinodontosaurus assemblage zone (AZ) and the Late Triassic Hyperodapedon AZ (Rauisuchus tiradentes). Between these two cenozones is t...