Australosomus Temporal range: | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | † Pholidopleuriformes |
Family: | † Pholidopleuridae |
Genus: | † Australosomus Pivetau, 1930 |
Type species | |
†Pristisomus merlei Priem, 1924 | |
Species [2] | |
See text |
Australosomus (meaning "southern body") 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 (British Columbia). [3] [4] [1]
The type species, Australosomus merlei from Madagascar, was first described as Pristisomus merlei by Ferdinand Priem. A new genus, Australosomus, was later erected for this species by Jean Piveteau. [5]
Australosomus is one of many genera to arise after the Permian-Triassic extinction event, only to die out during the Early Triassic, [4] possibly during a subsequent extinction event. [3]
Most species were marine, except for the African species, which were found in freshwater deposits.
The genus name Australosomus ("southern body") is inaccurate, as Australosomus is known as far north as Canada and Greenland, although the first known remains were described from Madagascar.
Australosomus contains the following species: [6]
Indeterminate remains are known from the Sulphur Mountain Formation of British Columbia and Alberta (Canada). [8] The remains of a potentially associated genus are known from the Late Triassic Chinle Formation of Arizona. [6] Potential remains are known from the Permian-Triassic boundary of Kenya. [9]
Australosomus was an elongate fish. The interlocking scales (3 to 4 times long as wide), deeply forked caudal fin all help to distinguish this genus. [10] It achieved standard lengths of about 100 mm (3.9 in) to 310 mm (12 in). [4]
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.
Coelurosauravus is an extinct genus of gliding reptile, known from the Late Permian of Madagascar. Like other members of the family Weigeltisauridae, members of this genus possessed long, rod-like ossifications projecting outwards from the body. These bony rods were not extensions of the ribs but were instead a feature unique to weigeltisaurids. It is believed that during life, these structures formed folding wings used for gliding flight, similar to living gliding Draco lizards.
Hovasaurus is an extinct genus of basal diapsid reptile. It lived in what is now Madagascar during the Late Permian and Early Triassic, being a survivor of the Permian–Triassic extinction event and the paleontologically youngest member of the Tangasauridae. Fossils have been found in the Permian Lower and Triassic Middle Sakamena Formations of the Sakamena Group, where it is amongst the commonest fossils. Its morphology suggests an aquatic ecology.
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.
Laugia is an extinct genus of coelacanth fish which lived during the Induan age of the Early Triassic epoch in what is now Greenland. The type and only species, Laugia groenlandica, was collected from the Wordie Creek Formation and described by Erik Stensiö. The genus is named after Lauge Koch.
Whiteia is an extinct genus of prehistoric coelacanth fish which lived during the Triassic period. It is named after Errol White.
Watsonulus is an extinct genus of prehistoric ray-finned fish that lived during the Early Triassic epoch in what is now Madagascar. It may have also existed in what is now Himachal Pradesh, India, during the Induan age. The type species, described by Jean Piveteau, is Watsonia eugnathoides. Because "Watsonia" was preoccupied, the new genus name Watsonulus was later erected. The genus is named after David Meredith Seares Watson.
Broughia is an extinct genus of marine holostean ray-finned fish that lived during the Induan age of the Early Triassic epoch in what is now Greenland. Fossils were found in the Wordie Creek Formation. A potential concurrent record is also known from Madagascar.
Ospia is an extinct genus of neopterygian ray-finned fish that lived during the Induan age of the Early Triassic epoch in what is now Greenland. Fossils were found in the Wordie Creek Formation.
Parasemionotus is an extinct genus of prehistoric bony fish that lived in the Induan age of the Early Triassic epoch in what is now Madagascar. It is the name giving genus of the family Parasemionotidae and the order Parasemionotiformes.
Paracentrophorus is an extinct genus of prehistoric ray-finned fish that lived during the Induan age of the Early Triassic epoch in what is now Madagascar. The type species is Paracentrophorus madagascariensis (monotypy).
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.
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.
Boreosomus is an extinct genus of Triassic marine ray-finned fish. It was first described from the Arctic island of Spitsbergen, hence its genus name, but was later also discovered in other parts of the world. The type species is Boreosomus arcticus.
Pristisomus is an extinct genus of prehistoric bony fish that lived during the Anisian age in what is now New South Wales, Australia. Fossils are derived from the Sydney sandstone.
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.
Barasaurus is an extinct genus of owenettid procolophonoid parareptile known from the Late Permian and Early Triassic of Madagascar. It contains a single species, Barasaurus besairiei.
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.
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.
Eigil Hans Aage Nielsen was a Danish paleontologist, who specialized in fossil vertebrate anatomy, particularly of Triassic bony fish.