Anaethalion Temporal range: | |
---|---|
Anaethalion knorri | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Elopiformes |
Genus: | † Anaethalion White, 1938 |
Species | |
See text |
Anaethalion is an extinct genus of prehistoric marine and freshwater ray-finned fish related to modern tarpons and ladyfish. It is known from the Late Jurassic to the Early Cretaceous of Europe and northeasterrn Asia (Germany, Italy, the United Kingdom and Russia), roughly encompassing the Tethys Ocean. [1] [2]
It is the earliest known member of the Elopiformes and the Elopomorpha in general. [3] The earliest known species are marine, but later species are found in freshwater habitats.
The following species are known: [1]
An undescribed species is known from the Albian of Italy. The genus Aethalionopsis was previously considered synonymous with Anaethalion, but is now known to be a fossil relative of the milkfish. Some authorities place some of its species (A. valdensis and the undescribed Italian species) with Aethalionopsis instead. [1] [4] [5]
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.
The Gonorynchiformes are an order of ray-finned fish that includes the important food source, the milkfish, and a number of lesser-known types, both marine and freshwater.
The Elopiformes are the order of ray-finned fish including the tarpons, tenpounders, and ladyfish, as well as a number of extinct types. They have a long fossil record, easily distinguished from other fishes by the presence of an additional set of bones in the throat.
Dapedium is an extinct genus of primitive neopterygian ray-finned fish. The first-described finding was an example of D. politum, found in the Lower Lias of Lyme Regis, on the Jurassic Coast of England. Dapedium lived in the late Triassic and Jurassic periods.
Pycnodus is an extinct genus of ray-finned fish from the Eocene period. It is wastebasket taxon, although many fossils from Jurassic or Cretaceous are assigned to this genus, only Eocene species, P. apodus is valid. As its name suggests, it is the type genus of Pycnodontiformes.
Pholidophorus is an extinct genus of stem-teleost fish. Numerous species were assigned to this genus in the past, but only the type species Pholidophorus latiusculus, from the Late Triassic of Europe, is considered to be a valid member of the genus today.
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.
Aspidorhynchiformes is an extinct order of ray-finned fish. It contains only a single family, the Aspidorhynchidae. Members of the group are noted for their elongated, conical rostrums, of varying length, formed from fused premaxillae. The range of the group extends from the Middle Jurassic to the late Paleocene.
Pachythrissops is an extinct genus of ray-finned fish. It contains two species, P. laevis from the Purbeckian of England and P. propterus from the Tithonian of Germany. A third species, P. vectensis, has been reassigned to the elopiform genus Arratiaelops. Pachythrissops is often regarded as one of the most primitive members of the order Ichthyodectiformes; however, a phylogenetic analysis by Cavin et al. (2013) placed it and the related genus Ascalabothrissops outside the group.
Pycnodontiformes is an extinct order of primarily marine bony fish. The group first appeared during the Late Triassic and disappeared during the Eocene. The group has been found in rock formations in Africa, Asia, Europe, North and South America. They were small to middle-sized fish, generally with laterally-compressed deep bodies, some with almost circular outlines, adapted for manuverability in reef-like environments, though the group was morphologically diverse. Most, but not all members of the groups had jaws with round and flattened teeth, well adapted to crush food items (durophagy), such as echinoderms, crustaceans and molluscs. Some pyncodontiformes developed piranha like teeth used for eating flesh. Most species inhabited shallow marine reef environments, while a handful of species lived in freshwater or brackish conditions. While rare during the Triassic and Early-Middle Jurassic, Pycnodontiformes became abundant and diverse during the Late Jurassic, exhibiting a high but relatively static diversity during the Early Cretaceous. At the beginning of the Late Cretaceous they reached their apex of morphological and species diversity, after which they began to gradually decline, with a more sudden decline at the end of the Cretaceous due to the collapse of reef ecosystems, finally becoming extinct during the Eocene. They are considered to belong to the Neopterygii, but their relationship to other members of that group is uncertain.
Aethalionopsis is an extinct genus of prehistoric freshwater bony fish from the Early Cretaceous of western Europe. Formerly classified as a species of the elopiform Anaethalion, it is now known to be a relative of the modern milkfish (Chanos) in order Gonorhynchiformes. It was previously placed as a basal member of the suborder Chanoidei, but is now more often placed as a basal member of the subfamily Chaninae of the family Chanidae, placing it closer to the extant Chanos.
Orthocormus is an extinct genus of prehistoric pachycormiform bony fish. It is known from three species found in Late Jurassic (Kimmeridgian) aged plattenkalk deposits in Bavaria, Germany. The species "Hypsocormus" tenuirostris Woodward 1889 from the late Middle Jurassic (Callovian) Oxford Clay is not closely related to the type species of Hypsocormus, and is more closely related to Orthocormus + Protosphyraena, and thus has sometimes been referred to in open nomenclature as Orthocormus? tenuirostris. The species of Orthocormus reached over a metre in length, and are thought to have been pelagic predators.
Crossognathiformes is an extinct order of ray-finned fish that lived from the Late Jurassic to the Eocene. Its phylogenetic placement is disputed; some authors have recovered it as part of the teleost stem group, while others place it in a basal position within crown group Teleostei.
This list of fossil fishes described in 2013 is a list of new taxa of placoderms, fossil cartilaginous fishes and bony fishess of every kind that have been described during the year 2013. The list only includes taxa at the level of genus or species.
Orthogonikleithrus is a genus of extinct ray-finned fish that lived during the Late Jurassic period. It lived in lagoonal and restricted shallow subtidal zones.
This list of fossil fishes described in 2019 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes, and other fishes of every kind that were described during the year 2019, as well as other significant discoveries and events related to paleoichthyology that occurred in 2019.
This list of fossil fishes described in 2020 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fishes, bony fishes, and other fishes of every kind that were described during the year 2020, as well as other significant discoveries and events related to paleoichthyology that occurred in 2020.
The Sainte-Barbe Clays Formation is a geological formation in Belgium. It is found in localised areas of the northern margin of the Mons Basin, alongside the equivalently aged Hautrage and Baudour Clay Formations. It is Upper Barremian-Lower Aptian in age. It predominantly consists of laminated clay, with some lignite. It is well known for the "Iguanodon sinkhole" locality near Bernissart where many specimens of Iguanodon bernissartensis were described by Louis Dollo in the late 19th century.
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.