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...

Tanytrachelos ahynis (n.gen., n. sp.) is a lepidosaur from the Late Triassic Dan River Group (Newark Supergroup) of North Carolina and Virginia. The new reptile has gracile proportions similar to Tanystropheus (Middle Triassic) and is referred to the family Tanystropheidae of the suborder Prolacertiformes. Unlike Tanystropheus, Tanytrachelos has relatively short cervical vertebrae bearing splin...

• New Triassic-Jurassic section, paleontological-geochemical data, open Panthalassa. Complete record, new δ 13 C org curve across the transition. Norian-Rhaetian and boundaries constrained by paleontological data. Four U–Pb dates Boundary support a long Rhaetian (∼8 Ma). global interpretation: variable carbon cycle dynamics, Panthalassa vs. Tethys. The end-Triassic mass extinction is one of big...

The biological extinction that occurred at the Permian-Triassic boundary represents the most extensive loss of species of any known event of the past 550 million years. There have been a wide variety of explanations offered for this extinction. In the present paper, a number of the more popular recent hypotheses are evaluated in terms of predictions that they make, or that they imply, concernin...