Norian in the context of "Rhaetian"

The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between 237 Ma and 201.4 Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. The corresponding series of rock beds is known as the Upper Triassic. The Late Triassic is divided into the Carnian, Norian and Rhaetian ages.

Many of the first dinosaurs evolved during the Late Triassic, including Plateosaurus, Coelophysis, Herrerasaurus, and Eoraptor. The Triassic–Jurassic extinction event began during this epoch and is one of the five major mass extinction events of the Earth.

The Carnian (less commonly, Karnian) is the lowermost stage of the Upper Triassic Series (or earliest age of the Late Triassic Epoch). It lasted from 237 to 227.3 million years ago (Ma). The Carnian is preceded by the Ladinian and is followed by the Norian. Its boundaries are not characterized by major extinctions or biotic turnovers, but a climatic event (known as the Carnian pluvial episode characterized by substantial rainfall) occurred during the Carnian and seems to be associated with important extinctions or biotic radiations. Another extinction occurred at the Carnian-Norian boundary, ending the Carnian age.

The Rhamphorhynchoidea forms one of the two suborders of pterosaurs and represents an evolutionary grade of primitive members of flying reptiles. This suborder is paraphyletic unlike the Pterodactyloidea, which arose from within the Rhamphorhynchoidea as opposed to a more distant common ancestor. Because it is not a completely natural grouping, Rhamphorhynchoidea is not used as a formal group in most scientific literature, though some pterosaur scientists continue to use it as an informal grouping in popular works, such as The Pterosaurs: From Deep Time by David Unwin, and in some formal studies. Rhamphorhynchoids were the first pterosaurs to have appeared, in the late Triassic Period (Norian age, about 210 million years ago). Unlike their descendants, the pterodactyloids, most rhamphorhynchoids had teeth and long tails, and most species lacked a bony crest, though several are known to have crests formed from soft tissue like keratin. They were generally small, with wingspans rarely exceeding 2.5 meters, though one specimen alluded to by Alexander Stoyanow would be among the largest pterosaurs of all time with a wingspan of 10 meters, comparable to the largest azhdarchids. However, this alleged giant Jurassic pterosaur specimen is not recorded anywhere outside the original Time article. Nearly all rhamphorhynchoids had become extinct by the end of the Jurassic Period, though some anurognathids persisted to the early Cretaceous. The family Wukongopteridae, which shows a mix of rhamphorhynchoid and pterodactyloid features, is known from the Daohugou Beds which are most commonly dated to the Jurassic, but a few studies give a Cretaceous date. Furthermore, remains of a non-pterodactyloid from the Candeleros Formation extend the presence of basal pterosaurs into at least the early Late Cretaceous.

The Blomidon Formation is a unit of Upper Triassic (Norian–Rhaetian) sedimentary rocks, which outcrops in Nova Scotia. At outcrop they reach a maximum thickness of 365 metres (1,198 ft), but up to 1,168 metres (3,832 ft) has been proven from well data and a thickness of up to 2,500 metres (8,200 ft) has been inferred from seismic reflection data. It overlies the mainly Carnian Wolfville Formation and underlies the North Mountain Basalt. The type section is exposed between Cape Blomidon (45°17′43″N 64°19′55″W / 45.29528°N 64.33194°W / 45.29528; -64.33194) and Paddy Island (45°11′51″N 64°21′34″W / 45.197372°N 64.359411°W / 45.197372; -64.359411).

Isanosaurus ("North-eastern Thailand lizard") is an extinct genus of sauropod dinosaur from Thailand. It was originally dated to approximately 219-199  million years ago during the Late Triassic (late Norian to Rhaetian stages), which would make it one of the oldest known sauropods. Its age was later considered uncertain, and may be Early Jurassic or even as young as Late Jurassic. The only species is Isanosaurus attavipachi. Though important for the understanding of sauropod origin and early evolution, Isanosaurus is poorly known. Exact relationships to other early sauropods remain unresolved.

Coelophysis (/sɛˈlɒfɪsɪs/ se-LOF-iss-iss traditionally; /ˌsɛloʊˈfaɪsɪs/ SEL-oh-FY-siss or /ˌsiːloʊˈfaɪsɪs/ SEE-loh-FY-siss) is an extinct genus of coelophysid theropod dinosaurs that lived approximately 215 to 201.4 million years ago during the late Triassic period from the middle Norian to Rhaetian age in what is now the southwestern United States. Megapnosaurus was once considered to be a species within this genus, but this interpretation has been challenged and the genus Megapnosaurus is now considered valid.

Coelophysis was a small, slenderly built, ground-dwelling, bipedal carnivore that could grow up to 3 m (9.8 ft) long. It is one of the earliest known dinosaur genera. Scattered material representing similar animals has been found worldwide in some Late Triassic and Early Jurassic formations.

Probainognathia is one of the two major subgroups of the clade Eucynodontia, the other being Cynognathia. The earliest forms were carnivorous and insectivorous, though some groups eventually also evolved herbivorous diets. The earliest and most basal probainognathian is the Middle Triassic (Anisian) aged Lumkuia, from South Africa, though probainognathians would not become prominent until the mid Norian stage of the Late Triassic. Three groups survived the extinction at the end of Triassic: Tritheledontidae and Tritylodontidae, which both survived until the Jurassic—the latter even into the Cretaceous (Montirictus and Xenocretosuchus)—and Mammaliaformes, which includes the mammals.

Aetosaurus is an extinct genus of pseudosuchian reptile belonging to the order Aetosauria. It is generally considered to be the most primitive aetosaur. Three species are currently recognized: A. ferratus, the type species from Germany and Italy; A. crassicauda from Germany; and A. arcuatus from eastern North America. Additional specimens referred to Aetosaurus have been found in the Chinle Group of the southwestern United States, and the Fleming Fjord Formation of Greenland. Specimens of Aetosaurus occur in Norian-age strata.