The discovery of the first definitively correlated earliest Jurassic (200 million years before present) tetrapod assemblage (Fundy basin, Newark Supergroup, Nova Scotia) allows reevaluation of the duration of the Triassic-Jurassic tetrapod extinction event. Present are tritheledont and mammal-like reptiles, prosauropod, theropod, and ornithischian dinosaurs, protosuchian and sphenosuchian croco...

Mesozoic marine reptiles and modern marine mammals are often considered ecological analogs, but the extent of their similarity is largely unknown. Particularly important is the presence/absence of deep-diving suction feeders among Mesozoic marine reptiles because this would indicate the establishment of mesopelagic cephalopod and fish communities in the Mesozoic. A recent study suggested that d...

Current characterizations of early dinosaur evolution are incomplete: existing palaeobiological and phylogenetic scenarios are based on a fossil record dominated by saurischians and the implications of the early ornithischian record are often overlooked. Moreover, the timings of deep phylogenetic divergences within Dinosauria are poorly constrained owing to the absence of a rigorous chronostrat...

A new species of the erythrosuchid archosauriform reptile Garjainia Ochev, 1958 is described on the basis of disarticulated but abundant and well-preserved cranial and postcranial material from the late Early Triassic (late Olenekian) Subzone A of the Cynognathus Assemblage Zone of the Burgersdorp Formation (Beaufort Group) of the Karoo Basin of South Africa. The new species, G. madiba, differs...

Contrary to the fast radiation of most metazoans after the end-Permian mass extinction, it is believed that early marine reptiles evolved slowly during the same time interval. However, emerging discoveries of Early Triassic marine reptiles are questioning this traditional view. Here we present an aberrant basal ichthyosauriform with a hitherto unknown body design that suggests a fast radiation ...

We present a holistic approach to the study of early archosauriform evolution by integrating body and track records. The ichnological record supports a Late Permian-Early Triassic radiation of archosauriforms not well documented by skeletal material, and new footprints from the Upper Permian of the southern Alps (Italy) provide evidence for a diversity not yet sampled by body fossils. The integ...

Delayed Earth system recovery following the end-Permian mass extinction is often attributed to severe ocean anoxia. However, the extent and duration of Early Triassic anoxia remains poorly constrained. Here we use paired records of uranium concentrations ([U]) and (238)U/(235)U isotopic compositions (δ(238)U) of Upper Permian-Upper Triassic marine limestones from China and Turkey to quantify va...

The tetrapod ichnotaxon Apatopus lineatus is a relatively uncommon component of Late Triassic footprint assemblages. This might be related to the semi-aquatic lifestyle of the trackmakers, which were almost certainly phytosaurs and whose skeletons are known from coeval deposits with a Pangea-wide distribution. Originally described from the Passaic Formation of New Jersey, Apatopus lineatus has ...

the study area is situated in the middle part of the tabas block. it contains outcrops of rocks that formed along longitudinal faults in early cimmerian orogenic phase. the basin subsided along these faults from the late triassic to early cretaceous, which include two sedimentary cycles. a sedimentary cycle, related to upper triassic to bajocian is known as shemshak group. another sedimentary c...

The biotic recovery from Earth's most severe extinction event at the Permian-Triassic boundary largely reestablished the preextinction structure of marine trophic networks, with marine reptiles assuming the predator roles. However, the highest trophic level of today's marine ecosystems, i.e., macropredatory tetrapods that forage on prey of similar size to their own, was thus far lacking in the ...