Aetheretmon Temporal range: | |
---|---|
Aetheretmon valentiacum fossil | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Family: | † Strepheoschemidae |
Genus: | † Aetheretmon White, 1927 |
Species: | †A. valentiacum |
Binomial name | |
†Aetheretmon valentiacum White, 1927 | |
Synonyms | |
AetherthmonWhite, 1927 |
Aetheretmon is an extinct genus of freshwater and estuarine ray-finned fish that lived during the early Mississippian (Dinantian) age in what is now Europe, including Scotland, Belarus, and Russia. [1] It contains only the species A. valentiacum. [2] This genus has the oldest known actinopterygian growth series, indicating that juvenile Aetheretmon had tails similar to those of modern teleosts, but unlike teleosts, their upper tails continued to grow throughout their lives instead of truncating early. [3] [4] Initially classified as a "palaeoniscid", later studies have recovered it as a stem-neopterygian, or more recently a stem-actinopteran. [2] [3]
Actinopterygii, members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of skin supported by radially extended thin bony spines called lepidotrichia, as opposed to the bulkier, fleshy lobed fins of the sister class Sarcopterygii. Resembling folding fans, the actinopterygian fins can easily change shape and wetted area, providing superior thrust-to-weight ratios per movement compared to sarcopterygian and chondrichthyian fins. The fin rays attach directly to the proximal or basal skeletal elements, the radials, which represent the articulation between these fins and the internal skeleton.
Chondrostei is a group of non-neopterygian ray-finned fish. While the term originally referred to the paraphyletic grouping of all non-neopterygian ray-finned fish, it was redefined by Patterson in 1982 to be a clade comprising the Acipenseriformes and their extinct relatives.
Neopterygii is a subclass of ray-finned fish (Actinopterygii). Neopterygii includes the Holostei and the Teleostei, of which the latter comprise the vast majority of extant fishes, and over half of all living vertebrate species. While living holosteans include only freshwater taxa, teleosts are diverse in both freshwater and marine environments. Many new species of teleosts are scientifically described each year.
The Palaeonisciformes, commonly known as "palaeoniscoids" are an extinct grouping of primitive ray-finned fish (Actinopterygii), spanning from the Silurian/Devonian to the Cretaceous. They are generally considered paraphyletic, but their exact relationships to living ray-finned fish are uncertain. While some and perhaps most palaeoniscoids likely belong to the stem-group of Actinopteryii, it has been suggested that some may belong to the crown group, with some of these possibly related to Cladistia and/or Chondrostei. Many palaeoniscoids share a conservative body shape and a similar arrangement of skull bones, though paleoniscoids as a whole exhibit considerable diversity in body shape.
Ichthyodectiformes is an extinct order of marine stem-teleost ray-finned fish. The order is named after the genus Ichthyodectes, established by Edward Drinker Cope in 1870. Ichthyodectiforms are usually considered to be some of the closest relatives of the teleost crown group.
Pachycormus is an extinct genus of pachycormiform ray-finned fish known from the Early Jurassic of Europe.
Styracopterus is an extinct genus of ray-finned fish that lived during the Tournaisian stage of the Mississippian epoch of Scotland and Eastern European Platform, Russia.
Cosmoptychius is an extinct genus of freshwater and estuarine ray-finned fish that lived during the Mississippian epoch. It contains a single species, C. striatus from the Visean of Scotland. It has a wide stratigraphic range in the Wardie Shale, with many specimens known.
Daitingichthys is an extinct genus of prehistoric marine ray-finned fish that lived during the Late Jurassic period. It contains a single species, D. tischlingeri from the early Tithonian-aged Mörnsheim Formation of the Solnhofen Limestone, Germany. It is thought to be a stem-elopiform, related to modern ladyfish and tarpons.
Cycloptychius is an extinct genus of prehistoric freshwater & marine ray-finned fish that existed throughout much of the Carboniferous period in Eurasia, and possibly into the Early Permian in South Africa. It was a member of the Rhadinichthyidae, a family of basal ray-finned fish that was formerly placed in the now-paraphyletic order Palaeonisciformes.
Strepheoschema is an extinct genus of prehistoric bony fish that lived during the early Mississippian (Tournaisian–Visean) in what is now Berwickshire, Scotland, and Northumberland, England. Fossils were recovered from the Ballagan Formation.
Prohalecites is an extinct genus of ray-finned fish from the Ladinian and possibly Carnian (Triassic) of Italy. It is the oldest known teleosteomorph, a group that includes extant teleosts and their close fossil relatives.
Phanerosteon is an extinct genus of prehistoric bony fish from the Carboniferous period. The type species, P. mirabile, was recovered from the Calciferous sandstone series (Pennsylvanian), Scotland. A second species, P. phonax was described from the Serpukhovian aged Bear Gulch Limestone lagerstätte in Montana, United States.
Cavenderichthys is an extinct genus of prehistoric freshwater ray-finned fish from the Late Jurassic. It contains a single species, C. talbragarensis from the Talbragar Fish beds of New South Wales, Australia.
Cladistia is a clade of bony fishes whose only living members are the bichirs of tropical Africa. Their major synapomorphies are a heterocercal tail in which the dorsal fin has independent rays, and a posteriorly elongated parasphenoid.
The Ballagan Formation is a geologic formation in Scotland and England. It preserves fossils dating back to the early part of the Carboniferous period. Its name comes from the "Ballagan Beds" of Ballagan Glen, near Strathblane, which has a good example of this geological formation.
This list of fossil fishes described in 2016 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes and other fishes of every kind that have been described during the year 2016, as well as other significant discoveries and events related to paleontology of fishes that occurred in the year 2016. The list only includes taxa at the level of genus or species.
Archaeomaenidae is an extinct family of stem-teleost fish found in freshwater environments of Jurassic New South Wales of Australia, China, and Antarctica, and in Lower Cretaceous New South Wales and Mongolia.
Dapediidae is an extinct family of neopterygian ray-finned fish that lived from the Middle Triassic to Late Jurassic. It is the only family of the order Dapediiformes. Its members were historically placed within the ginglymodian family Semionotidae, but were moved to their own family in 1966.
Pholidophoridae is an extinct family of primitive stem-teleost fish that lived during the Triassic period, from the Anisian age of the Middle Triassic to the Norian age of the Late Triassic. Most of the genera are from Europe, but one (Malingichthys) is known from China. The pholidophorids were historically united with several other stem-teleost lineages into the order Pholidophoriformes, but Pholidophoriformes in its traditional sense is now considered paraphyletic with respect to crown group teleosts.