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Cosmoselachus
''Cosmoselachus'' is an extinct genus of symmoriiform chondrichthyan from the Upper Carboniferous ( Mississippian subperiod) aged Fayetteville Shale of Arkansas, United States. The genus contains a single species, ''C. mehlingi'', which is known from a partial specimen that includes the cranium, jaws, gill arches, pectoral fins, and teeth. Discovery and naming The ''Cosmoselachus'' holotype specimen, AMNH FF 20509, was discovered in 1979 in sediments of the Fayetteville Shale near Cove Creek in Searcy County, Arkansas, United States. Since its discovery, the specimen has been damaged and it has experienced pyrite decay while in storage at AMNH. The fossil consists of the nearly complete lower jaws with teeth, a partial upper jaw and basicranium, gill arch elements, cartilage from a partial pectoral girdle, pectoral fins and fin impressions. In 2024, Allison Bronson and others described ''Cosmoselachus mehlingi'' as a new genus and species of shark-like cartilaginous fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fayetteville Shale
The Fayetteville Shale is a geologic formation (geology), formation of Mississippian age (354–323 million years ago) composed of tight shale within the Arkoma Basin of Arkansas and Oklahoma. It is named for the city of Fayetteville, Arkansas, and requires hydraulic fracturing to release the natural gas contained within. Nomenclature Named by Frederick Willard Simonds in 1891, Simonds recognized what is now the Fayetteville Shale as three separate formations overlying the now abandoned Wyman Sandstone: the Fayetteville Shale, the Batesville Sandstone, and the Marshall Shale. In 1904, the name "Fayetteville Shale" replaced all three of these names. The Fayetteville Shale that Simonds recognized is now considered as the lower Fayetteville Shale. Simonds' Batesville Sandstone was found to be the same as the Wyman Sandstone, and replaced the name "Wyman Sandstone", while Simonds' Batesville Sandstone became known as the "Wedington Sandstone Member" presumably after Wedington Mountai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2024 In Paleoichthyology
This list of fossil fish research presented in 2024 is a list of new fossil taxa of Agnatha, jawless vertebrates, placoderms, Chondrichthyes, cartilaginous fishes, Osteichthyes, bony fishes, and other fishes that were binomial nomenclature, described during the year, as well as other significant discoveries and events related to paleoichthyology that occurred in 2024. Jawless vertebrates Jawless vertebrate research * A study on the evolutionary history of hagfishes, as indicated by the fossil record and molecular data, is published by Brownstein & Near (2024), who consider the hagfish crown group to be a lineage with Early Permian origin and a long history in continental slope settings. * Brookfield (2024) interprets ''Jamoytius, Jamoytius kerwoodi'' as a probable detritivore or herbivore feeding on ''Dictyocaris'' (interpreted by the author as possible algal Thallus, thalli). * Evidence interpreted as indicating that oral plates of pteraspid heterostracans had a mechanical f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falcatid
Falcatidae is a family of Paleozoic cartilaginous fish belonging to the order Symmoriiformes. Members of this family include ''Falcatus'', a small fish from the Bear Gulch Limestone of Montana. The family first appeared around the start of the Carboniferous, and there is some evidence that they survived well into the early Cretaceous, though its putative Cretaceous members were also argued to be more likely neoselachians. Genera *'' Denaea'' Ginter, M., Hampe., Duffin, C. 2010. Handbook of Paleoichthyology: Volume 3D- Paleozoic Elasmobranchii teeth. Verlag Dr. Freidrich Pfeil *''Falcatus'' *''Ozarcus''? *'' Stethacanthulus'' *''Cosmoselachus'' *''Cretacladoides''? – possible Early Cretaceous (Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 137.05 ± 0.2 Ma and 132.6 ± 0.2 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretac ...) member of the family ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous
The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the Permian Period, Ma. It is the fifth and penultimate period of the Paleozoic era and the fifth period of the Phanerozoic eon (geology), eon. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian (geology), Mississippian and the later Pennsylvanian (geology), Pennsylvanian. The name ''Carboniferous'' means "coal-bearing", from the Latin ("coal") and ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern "system" names, it was coined by geologists William Conybeare (geologist), William Conybeare and William Phillips (geologist), William Phillips in 1822, based on a study of the British rock succession. Carboniferous is the per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Museum Of Natural History
The American Museum of Natural History (AMNH) is a natural history museum on the Upper West Side of Manhattan in New York City. Located in Theodore Roosevelt Park, across the street from Central Park, the museum complex comprises 21 interconnected buildings housing 45 permanent exhibition halls, in addition to a planetarium and a library. The museum collections contain about 32 million specimens of plants, animals, fungi, fossils, minerals, rocks, meteorites, human remains, and human cultural artifacts, as well as specialized collections for frozen tissue and genomic and astrophysical data, of which only a small fraction can be displayed at any given time. The museum occupies more than . AMNH has a full-time scientific staff of 225, sponsors over 120 special field expeditions each year, and averages about five million visits annually. The AMNH is a private 501(c)(3) organization. The naturalist Albert S. Bickmore devised the idea for the American Museum of Natural History in 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladoselache
''Cladoselache'' ("branch shark") is an Extinction, extinct genus of shark-like chondrichthyan (cartilaginous fish) from the Late Devonian (Famennian) of North America. It was similar in body shape to modern Lamnidae, lamnid sharks (such as Isurus, mako sharks and the great white shark), but was not closely related to lamnids or to any other modern (selachian) shark. As an early chondrichthyan, it had yet to evolve traits of modern sharks such as accelerated tooth replacement, a loose jaw suspension, enameloid teeth, and possibly Clasper, claspers. Some 20th century studies considered ''Cladoselache'' to be a Basal (phylogenetics), basal (early-diverging) member of Elasmobranchii, the fork of cartilaginous fish which leads to modern sharks and rays. More recent studies have identified distinctive traits of the chondrocranium (cartilaginous braincase), dorsal fin spines, and pectoral fin bases. These newly identified features support a close relationship to Symmoriiformes, symmorii ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferromirum
''Ferromirum'' is an extinct genus of symmoriiform cartilaginous fish known from the late Devonian (mid Famennian) Ibâouane Formation in the southeastern Anti-Atlas of Morocco, with a single species ''Ferromirum oukherbouchi''. It is known from a single well preserved skeleton, which is of a small individual less than half a metre in length. The jaws and hyoid arch are preserved uncrushed. The skull has large orbits (eye sockets) which have sclerotic rings. The teeth are small and have a cladodont This is a typical Cladodont tooth, of a Glikmanius.html" ;"title="shark called ''Glikmanius">shark called ''Glikmanius'' Cladodont (from Latin cladus, meaning branch and Greek Odon, meaning tooth) is the term for a common category of early Devoni ... morphology. The body is slender. The first dorsal fin has a smooth fin spine, which curves posteriorly towards its tip. References Symmoriiformes Late Devonian cartilaginous fish Devonian cartilaginous fish of Africa Fossils ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladogram
A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not show how ancestors are related to descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with the same cladogram. A cladogram uses lines that branch off in different directions ending at a clade, a group of organisms with a last common ancestor. There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit the traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holocephali
Holocephali (Sometimes spelled Holocephala; Romanization of Greek, Greek for "complete head" in reference to the fusion of Palatoquadrate, upper jaw with the rest of the skull) is a Subclass (biology), subclass of Chondrichthyes, cartilaginous fish. While the only living holocephalans are three families within a single Order (biology), order which together are commonly known as chimaeras, the group includes many extinct orders and was far more diverse during the Paleozoic and Mesozoic Era (geology), eras. The earliest known fossils of holocephalans date to the Middle Devonian period, and the group likely reached its peak diversity during the following Carboniferous period. Molecular clock studies suggest that the subclass diverged from its closest relatives, Elasmobranchii, elasmobranchs such as sharks and Batomorphi, rays, during the Early Devonian or Silurian period. Extinct holocephalans are typically divided into a number of orders, although the interrelationships of these gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symmoriiformes
Symmoriiformes is an extinct order of cartilaginous fish. Originally named Symmoriida by Zangerl (1981), the name has since been corrected to Symmoriiformes to avoid confusion with a family. The symmoriiform fossils record begins during the late Devonian, and most had become extinct by the start of the Permian, with the genus '' Dwykaselachus'' from the Artinskian-Kungurian of South Africa being the latest known uncontroversial occurrence. Teeth described from the Valanginian of France and Austria indicate that members of the family Falcatidae might have survived until the Early Cretaceous; however, it has since been proposed that these teeth more likely belonged to neoselachian sharks. Fossil distribution Fossil evidence of Symmoriida have been found at Bear Gulch, Fergus County, Montana, Bethel Quarry, Pike County, Indiana, Kinshozan quarry, Alaska, Gifu Prefecture, Japan, Bashkortostan, Russian Federation and possibly also France. Classification Symmoriiformes were previ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetic Analyses
In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as Computational phylogenetics, phylogenetic inference. It infers the relationship among organisms based on empirical data and observed heritable traits of DNA sequences, protein amino acid sequences, and Morphology (biology), morphology. The results are a phylogenetic tree—a diagram depicting the hypothesis, hypothetical relationships among the organisms, reflecting their inferred evolutionary history. The tips of a phylogenetic tree represent the observed entities, which can be living Taxon, taxa or fossils. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the taxa represented on the tree. An unrooted tree diagram (a network) makes no assumption about directionality of character state transformation, and does not show the origin or "root" of the taxa in questi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Name (zoology)
In zoological nomenclature, the specific name (also specific epithet, species epithet, or epitheton) is the second part (the second name) within the scientific name of a species (a binomen). The first part of the name of a species is the name of the genus or the generic name. The rules and regulations governing the giving of a new species name are explained in the article species description. For example, the scientific name for humans is ''Homo sapiens'', which is the species name, consisting of two names: ''Homo'' is the " generic name" (the name of the genus) and ''sapiens'' is the "specific name". Etymology Historically, ''specific name'' referred to the combination of what are now called the generic and specific names. Carl Linnaeus, who formalized binomial nomenclature, made explicit distinctions between specific, generic, and trivial names. The generic name was that of the genus, the first in the binomial, the trivial name was the second name in the binomial, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
