The dentitions of several presumed herbivorous Triassic reptiles are described and discussed. Some chan)!;es in dentitions with wowth suggest that juveniles were insectivorous. The appearance of these forms may have been facilitated by noral changes which took place in the early

A lycopsid reproductive organ from the Koipato Group in southern Humboldt Range, Nevada, is described. It was found fine-grained volcanogenic turbitides of mid-Spathian age derived volcanic arc. The strobilus preserved as an imprint with small amounts organic material. shape organ, well sporophylls, resemble those genus Pleuromeia, especially Pleuromeia sternbergii. Immature spores extracted ma...

The holotype specimen of the Late Triassic dinosauriform Caseosaurus crosbyensis is redescribed and evaluated phylogenetically for the first time, providing new anatomical information and data on the earliest dinosaurs and their evolution within the dinosauromorph lineage. Historically, Caseosaurus crosbyensis has been considered to represent an early saurischian dinosaur, and often a herrerasa...

Goudemand et al. replot a subset of our well-constrained data using a new Early Triassic biostratigraphic scheme based on a lower-resolution ammonoid zonation scheme and hypothetical ammonoid-conodont correlation to produce a less distinct seawater temperature history. We dispute their unsubstantiated correlation and, consequently, their allegations.

The current Triassic chronostratigraphic scale is a hierarchy of three series divided into seven stages, divided further into 15 substages. Ammonoid and conodont biostratigraphies provide the primary basis for chronostratigraphic definition based on global stratotype sections and points (GSSP). I propose that Triassic chronostratigraphic definition should rely entirely on ammonoid biochronologi...

Nonmarine fluvial, eolian and lacustrine strata of the Chinle and Glen Canyon groups on the southern Colorado Plateau preserve tetrapod body fossils and footprints that are one of the world's most extensive tetrapod fossil records across the Triassic– Jurassic boundary. We organize these tetrapod fossils into five, time-successive biostratigraphic assemblages (in ascending order, Owl Rock, Rock...

Nonmarine fluvial, eolian and lacustrine strata of the Chinle and Glen Canyon groups in northeastern Arizona and adjacent areas preserve tetrapod body fossils and footprints that are one of the world’s most extensive tetrapod fossil records across the Triassic-Jurassic boundary. We organize these tetrapod fossils into five, time-successive biostratigraphic assemblages (in ascending order, Owl R...