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Dorypteridae
''Dorypterus'' is a small, extinct genus of prehistoric ray-finned bony fish. It lived during the Wuchiapingian stage of the late Permian epoch in what is now Germany (Kupferschiefer) and England (Marl Slate). It is a hypsisomatic bobasatraniiform with a high dorsal fin. Due to anatomical differences with other bobasatraniiforms, such as the presence of pelvic fins and the reduced scale cover, ''Dorypterus'' is placed in its own monotypic family, Dorypteridae. Two species are known, ''D. hoffmanni'' and ''D. althausi'', which are distinguished by differences in length of the dorsal fin. Whereas ''D. hoffmanni'' has a long dorsal fin, the dorsal fin of ''D. althausi'' is short. However, it is possible that this difference is due to sexual dimorphism, and that ''D. althausi'' represents the female phenotype of ''D. hoffmanni''. References See also * Prehistoric fish * List of prehistoric bony fish A ''list'' is any set of items in a row. List or lists may also ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bobasatraniiformes
Bobasatraniiformes is an extinct Order (biology), order of durophagous ray-finned fish that existed from the Lopingian, late Permian to the Middle Triassic in both marine life, marine and freshwater environments. The order includes two family (biology), families: Bobasatraniidae, with the genera ''Bobasatrania'', ''Ebenaqua'', and ''Ecrinesomus'', and Dorypteridae, comprising only the genus ''Dorypterus'' (monotypy). Bobasatraniiformes had a somewhat global distribution; fossils are found in Africa (Madagascar), Asia (Pakistan), Australia, Europe, and North America. Most bobasatraniiforms were small [ or less], but some species of ''Bobasatrania'' grew up to long. Bobasatraniiformes have a deepend body, a heterocercal caudal fin, and they often lack pelvic fins (present in ''Dorypterus'', very small in ''Ebenaqua''). Their dorsal and anal fins are often elongate (very elongate dorsal fin in ''Dorypterus''). The body is covered in rhombic scales (scale cover reduced in ''Dorypt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorypteridae
''Dorypterus'' is a small, extinct genus of prehistoric ray-finned bony fish. It lived during the Wuchiapingian stage of the late Permian epoch in what is now Germany (Kupferschiefer) and England (Marl Slate). It is a hypsisomatic bobasatraniiform with a high dorsal fin. Due to anatomical differences with other bobasatraniiforms, such as the presence of pelvic fins and the reduced scale cover, ''Dorypterus'' is placed in its own monotypic family, Dorypteridae. Two species are known, ''D. hoffmanni'' and ''D. althausi'', which are distinguished by differences in length of the dorsal fin. Whereas ''D. hoffmanni'' has a long dorsal fin, the dorsal fin of ''D. althausi'' is short. However, it is possible that this difference is due to sexual dimorphism, and that ''D. althausi'' represents the female phenotype of ''D. hoffmanni''. References See also * Prehistoric fish * List of prehistoric bony fish A ''list'' is any set of items in a row. List or lists may also ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lopingian
The Lopingian is the uppermost series/last epoch of the Permian. It is the last epoch of the Paleozoic. The Lopingian was preceded by the Guadalupian and followed by the Early Triassic. The Lopingian is often synonymous with the informal terms late Permian or upper Permian. The name was introduced by Amadeus William Grabau in 1931 and derives from Leping, Jiangxi in China. It consists of two stages/ ages. The earlier is the Wuchiapingian and the later is the Changhsingian. The International Chronostratigraphic Chart (v2018/07) provides a numerical age of 259.1 ±0.5 Ma. If a Global Boundary Stratotype Section and Point (GSSP) has been approved, the lower boundary of the earliest stage determines numerical age of an epoch. The GSSP for the Wuchiapingian has a numerical age of 259.8 ± 0.4 Ma. Evidence from Milankovitch cycles suggests that the length of an Earth day during this epoch was approximately 22 hours. The Lopingian ended with the Permian–Triassic extinction event. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marl Slate
The Marl Slate Formation is a geological formation in England. Despite its name, it is mostly dolomite rock. The Marl Slate Formation was formed about 273 to 259 million years ago, during the Guadalupian and Lopingian epochs of the late Permian period of the Earth's geological history. This formation is part of the Zechstein Group of rocks, and is equivalent to the Kupferschiefer of Germany. The Marl Slate Formation contains fossils including the conodont '' Mesogondolella britannica'' and the dorypterid fishes '' Dorypterus'' and ''Lekanichthys'', as well as the gliding reptile '' Weigeltisaurus'' and terrestrial reptile '' Protorosaurus'' The Marl Slate Formation outcrops in County Durham County Durham ( ), officially simply Durham,UK General Acts 1997 c. 23Lieutenancies Act 1997 Schedule 1(3). From legislation.gov.uk, retrieved 6 April 2022. is a ceremonial county in North East England.North East Assembly â€About North East E ... and Yorkshire in north-east Eng ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Prehistoric Bony Fish
A ''list'' is any set of items in a row. List or lists may also refer to: People * List (surname) Organizations * List College Albert A. List College of Jewish Studies, known simply as List College, is the undergraduate school of the Jewish Theological Seminary of America (JTS). It was founded by Solomon Schechter in 1909 as the Teachers Institute with the original goa ..., an undergraduate division of the Jewish Theological Seminary of America * SC Germania List, German rugby union club Other uses * Angle of list, the leaning to either port or starboard of a ship * List (information), an ordered collection of pieces of information ** List (abstract data type), a method to organize data in computer science * List on Sylt, previously called List, the northernmost village in Germany, on the island of Sylt * ''List'', an alternative term for ''roll'' in flight dynamics * To ''list'' a building, etc., in the UK it means to designate it a listed building that may not be a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Fish
The evolution of fish began about 530 million years ago during the Cambrian explosion. It was during this time that the early chordates developed the skull and the vertebral column, leading to the first craniates and vertebrates. The first fish lineages belong to the Agnatha, or jawless fish. Early examples include ''Haikouichthys''. During the late Cambrian, eel-like jawless fish called the conodonts, and small mostly armoured fish known as ostracoderms, first appeared. Most jawless fish are now extinct; but the extant lampreys may approximate ancient pre-jawed fish. Lampreys belong to the Cyclostomata, which includes the extant hagfish, and this group may have split early on from other agnathans. The earliest Gnathostomata, jawed vertebrates probably developed during the late Ordovician period. They are first represented in the fossil record from the Silurian by two groups of fish: the armoured fish known as Placodermi, placoderms, which evolved from the ostracoderms; and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological properties, its behavior, and the products of behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code, or its genotype, and the influence of environmental factors. Both factors may interact, further affecting phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and then again in his 1982 book ''The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as cad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', which is when both biological sexes are phenotypically indistinguishable from each other. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerated dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Fin
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through convergent evolution they have independently evolved external superficial fish-like body plans adapted to their marine environments, including most numerously fish, but also mammals such as cetaceans (whales, dolphins, and porpoises), and even extinct ancient marine reptiles such as various known species of ichthyosaurs. Most species have only one dorsal fin, but some have two or three. Wildlife biologists often use the distinctive nicks and wear patterns which develop on the dorsal fins of large cetaceans to identify individuals in the field. The bony or cartilaginous bones that support the base of the dorsal fin in fish are called ''pterygiophores''. Functions The main purpose of the dorsal fin is to stabilize the animal against rollin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypy
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. In contrast, an oligotypic taxon contains more than one but only a very few subordinate taxa. Examples Just as the term ''monotypic'' is used to describe a taxon including only one subdivision, the contained taxon can also be referred to as monotypic within the higher-level taxon, e.g. a genus monotypic within a family. Some examples of monotypic groups are: Plants * In the order Amborellales, there is only one family, Amborellaceae and there is only one genus, '' Amborella'', and in this genus there is only one species, namely ''Amborella trichopoda.' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelvic Fins
Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two endochondrally-derived bony girdles attached to bony radials. Dermal fin rays (lepidotrichia) are positioned distally from the radials. There are three pairs of muscles each on the dorsal and ventral side of the pelvic fin girdle that abduct and adduct the fin from the body. Pelvic fin structures can be extremely specialized in actinopterygians. Gobiids and lumpsuckers modify their pelvic fins into a sucker disk that allow them to adhere to the substrate or climb structures, such as waterfalls. In priapiumfish, males have modified their pelvic structures into a spiny copulatory device that grasps the female during mating. File:Pelvic fin skeleton.png, Pelvic fin skeleton for ''Danio rerio'', zebrafish. File:Zuignap waarmee de zwartbekgrond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
