In the geologic timescale, the Olenekian is an age in the Early Triassic epoch; in chronostratigraphy, it is a stage in the Lower Triassic series. It spans the time between 251.2 Ma and 247.2 Ma. The Olenekian is sometimes divided into the Smithian and the Spathian subages or substages. The Olenekian follows the Induan and is followed by the Anisian.
The Induan is the first age of the Early Triassic epoch in the geologic timescale, or the lowest stage of the Lower Triassic series in chronostratigraphy. It spans the time between 251.9 Ma and 251.2 Ma. The Induan is sometimes divided into the Griesbachian and the Dienerian subages or substages. The Induan is preceded by the Changhsingian and is followed by the Olenekian.
Birgeria is a genus of carnivorous marine ray-finned fish from the Triassic period. Birgeria had a global distribution, with fossil known from Madagascar, Spitsbergen, Germany, Switzerland, Italy, Slovenia, China, Russia, Canada and Nevada, United States. The oldest fossils are from Griesbachian aged beds of the Wordie Creek Formation of East Greenland. Birgeria existed throughout the entire Triassic period, from the very beginning just after the Permian-Triassic mass extinction, up to the very end with its extinction during the Triassic-Jurassic mass extinction.
Axelia is an extinct genus of prehistoric lobe-finned fish, which belonged to the family of Coelacanthidae. It lived during the Smithian age of the Early Triassic epoch in what is now Spitsbergen, Svalbard. Fossils were found in the "Fish Niveau" of the Lusitaniadalen Member of the Vikinghøgda Formation.
Wimania is an extinct genus of coelacanth lobe-finned fish that lived during the Early Triassic epoch in what is now Svalbard. Fossils were found in the Smithian aged "Fish Niveau" of the Lusitaniadalen Member of the Vikinghøgda Formation. Wimania belongs to the family Coelacanthidae. It is named after Carl Wiman.
Australosomus is an extinct genus of prehistoric ray-finned fish that lived during the Early Triassic epoch in what is now Greenland, Kenya, Tanzania, Madagascar, South Africa and Canada.
Pteronisculus is an extinct genus of prehistoric ray-finned fish that lived during the Early Triassic and Middle Triassic epochs of the Triassic period worldwide.
Acrolepis is an extinct genus of prehistoric marine bony fish that lived from the Famennian stage of the Devonian to the early Triassic epoch. Some species from the Early Triassic of Tasmania are also ascribed to Acrolepis.
Mylacanthus is an extinct genus of prehistoric coelacanth lobe-finned fish that lived during the Smithian age of the Early Triassic epoch in what is now Svalbard.
Sassenia is an extinct genus of prehistoric coelacanth lobe-finned fish that lived during the Early Triassic epoch in what is now East Greenland and Svalbard.
Scleracanthus is an extinct genus of prehistoric coelacanth lobe-finned fish. It lived during the Early Triassic epoch in what is now Spitsbergen, Svalbard.
Bobasatrania is an extinct genus of prehistoric marine ray-finned fish that survived the Permian-Triassic extinction event. Fossils of Bobasatrania were found in beds of Changhsingian to Ladinian age. It was most speciose during the Early Triassic.
Ptycholepiformes are an extinct order of prehistoric ray-finned fish that existed during the Triassic period and the Early Jurassic epoch. The order includes the genera Acrorhabdus, Ardoreosomus, Boreosomus, Chungkingichthys, Ptycholepis, and Yuchoulepis. Although several families have been proposed, some studies place all these genera in the same family, Ptycholepididae.
The Wordie Creek Formation is an uppermost Permian and Lower Triassic geologic formation in Greenland, outcrops of which are located in Northeast Greenland National Park. In 2017, it was suggested to be raised to group status, as the Wordie Creek Group.
The Vikinghøgda Formation is a geologic formation in Svalbard, Norway. It preserves fossils dating back to the Early Triassic (Griesbachian-Spathian) period. It is split into three members, from oldest to youngest: the Deltadalen Member (Induan), Lusitaniadalen Member (Smithian), and Vendomdalen Member (Spathian). The formation can be found in central Spitsbergen, southern Spitsbergen, as well as the smaller islands of Barentsøya and Edgeøya. The type locality is positioned in the vicinity of Vikinghøgda and Sticky Keep, two low peaks along the southeast edge of Sassendalen in Spitsbergen. The two upper members of the Vikinghøgda Formation were previously grouped together as the Sticky Keep Formation.
The Vardebukta Formation is a geologic formation in Norway. It preserves fossils dating back to the Induan stage. Outcrops are known from the Hornsund area but also from Bellsund and Isfjorden areas.
Candelarialepis is an extinct genus of prehistoric marine ray-finned fish that lived during the Induan age of the Early Triassic epoch in what is now Nevada. It contains a single species, C. argentus. It was described from the Candelaria Formation.
Ardoreosomus is an extinct genus of marine ray-finned fish. It was described from the Induan aged Candelaria Formation of Nevada, United States, which was located near the equator during the Early Triassic epoch. It contains only one species, A. occidentalis (monotypy).
Parasemionotiformes is an extinct order of neopterygian ray-finned fish that existed globally during the Triassic period. It comprises the families Parasemionotidae and Promecosominidae. Many of the included genera are monotypic and most species lived during the Early Triassic epoch.
Pygopterus is an extinct genus of prehistoric bony fish that lived during the Wuchiapingian to Olenekian ages in what is now England, Germany, Greenland and Svalbard (Spitsbergen). It is one of the few genera of ray-finned fish known to cross the Permian-Triassic boundary.
