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Rhamdia Zongolicensis
''Rhamdia zongolicensis'' (common name: Zongolica catfish) is a species of three-barbeled catfish endemic to Mexico. Its specific name refers to Zongolica, the area in Veracruz state where it occurs. It is a cave fish similar to '' Rhamdia laticauda'' and '' Rhamdia reddelli'', and at times considered a junior synonym of the former. Habitat ''Rhamdia zongolicensis'' is only known to occur in a single cave, Cueva del Túnel (Cueva del Ostoc), where it lives in stagnant pools. Description ''Rhamdia zongolicensis'' grows to at least about standard length. It is related to the surface-dwelling '' Rhamdia laticauda'', considered to be its sister species. Because the surface species is nocturnal, and thereby adapted to darkness, the cave species shows only few new adaptations: elongated barbels and extreme ability to withstand starvation (at least seven months under experimental conditions). It also shows reduced pigmentation and smaller eyes. ''Rhamdia zongolicensis'' is morphologi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horst Wilkens
Horst may refer to: Science * Horst (geology), a raised fault block bounded by normal faults or graben People * Horst (given name) * Horst (surname) * ter Horst, Dutch surname * van der Horst, Dutch surname Places Settlements Germany * Horst, Steinburg, a municipality in the district of Steinburg in Schleswig-Holstein * Horst, Lauenburg, a municipality in the district of Lauenburg in Schleswig-Holstein * Horst, Mecklenburg-Vorpommern, a village and district in the municipality of Sundhagen, Mecklenburg-Vorpommern * , a district in the city of Gelsenkirchen, North Rhine-Westphalia * , a town in the municipality of Seevetal, Lower Saxony Netherlands * Horst aan de Maas, a municipality in the province of Limburg ** Horst, Limburg, the municipal seat of Horst aan de Maas * , a hamlet in the municipality of Ermelo, Gelderland * , a village in the municipality of Gilze en Rijen, North Brabant * Schothorst, , and , districts in the city and municipality of Amersfoort, Utrecht Polan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Measurement
Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish measured from the tip of the snout to the posterior end of the last vertebra or to the posterior end of the midlateral portion of the hypural plate. Simply put, this measurement excludes the length of the caudal (tail) fin. * Total length (TL) is the length of a fish measured from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body. Standard length measurements are used with Teleostei (most bony fish), while total length measurements are used with Myxini (hagfish), Petromyzontiformes (lampreys), and (usually) Elasmobranchii (sharks and rays), as well as some other fishes. Total length meas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxonomy Articles Created By Polbot
Taxonomy is the practice and science of categorization or classification (general theory), classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. Among other things, a taxonomy can be used to organize and index knowledge (stored as documents, articles, videos, etc.), such as in the form of a library classification system, or a Taxonomy for search engines, search engine taxonomy, so that users can more easily find the information they are searching for. Many taxonomies are hierarchy, hierarchies (and thus, have an intrinsic tree structure), but not all are. Originally, taxonomy referred only to the categorisation of organisms or a particular categorisation of organisms. In a wider, more general sense, it may refer to a categorisation of things or concepts, as well as to the principles underlying such a categorisation. Taxonomy organizes taxonomic uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic Fish Of Mexico
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Fish Of Mexico
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include non- salty mineral-rich waters such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/ sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes. Fresh water is the water resource that is of the most and immediate use to humans. Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of higher plants and most insects, amphibians, reptiles, mammals and birds need fresh water to survive. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cave Fish
Cavefish or cave fish is a generic term for fresh and brackish water fish adapted to life in caves and other underground habitats. Related terms are subterranean fish, troglomorphic fish, troglobitic fish, stygobitic fish, phreatic fish and hypogean fish.Romero, Aldemaro, editor (2001). ''The Biology of Hypogean Fishes.'' Developments in Environmental Biology of Fishes. Helfman, G.S. (2007). ''Fish Conservation: A Guide to Understanding and Restoring Global Aquatic Biodiversity and Fishery Resources'', pp. 41–42. Island Press. There are more than 200 scientifically described species of obligate cavefish found on all continents, except Antarctica. Although widespread as a group, many cavefish species have very small ranges and are seriously threatened.Fenolio, D.B.; Zhao, Y.; Niemiller, M.L.; and Stout, J. (2013). ''In-situ observations of seven enigmatic cave loaches and one cave barbel from Guangxi, China, with notes on conservation status.'' Speleobiology Notes 5: 19-33.Proud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heptapteridae
The Heptapteridae, or three-barbeled catfishes, are a family of catfish that originate from the Americas. Most species are restricted to South America, but '' Imparfinis lineatus'', '' Nemuroglanis panamensis'' and '' Pimelodella chagresi'' are native to Panama, and ''Rhamdia'' species occur as far north as Mexico. The name Heptapteridae is derived from Greek, ''hepta'' meaning seven and ''pteron'' meaning fin. The diversity of this family is poorly known, and many species are yet to be described. So far, some 211 species have been described. This family is equivalent to the previously recognized Rhamdiinae, a subfamily of the family Pimelodidae. However, molecular evidence shows this family is a part of the superfamily Pimelodoidea along with the Pimelodidae, Pseudopimelodidae, and '' Conorhynchos''. The skin of these fish is usually naked (scaleless). They exhibit three pairs of barbels. They have a large adipose fin, and their caudal fin is deeply forked. However, no extern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergent Evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy. The recurrent evolution of flight is a classic example, as flying insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are ''analogous'', whereas '' homologous'' structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions. The opposite of convergence is divergent evolution, where related species evolve different traits. Convergent evolution is similar to parallel evo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sister Species
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and taxon B are sister groups to each other. Taxa A and B, together with any other extant or extinct descendants of their most recent common ancestor (MRCA), form a monophyletic group, the clade AB. Clade AB and taxon C are also sister groups. Taxa A, B, and C, together with all other descendants of their MRCA form the clade ABC. The whole clade ABC is itself a subtree of a larger tree which offers yet more sister group relationships, both among the leaves and among larger, more deeply rooted clades. The tree structure shown connects through its root to the rest of the universal tree of life. In cladistic standards, taxa A, B, and C may represent specimens, species, genera, or any other taxonomic units. If A and B are at the same taxonomic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Junior Synonym
The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linnaeus was the first to give a scientific name (under the currently used system of scientific nomenclature) to the Norway spruce, which he called ''Pinus abies''. This name is no longer in use, so it is now a synonym of the current scientific name, ''Picea abies''. * In zoology, moving a species from one genus to another results in a different binomen, but the name is considered an alternative combination rather than a synonym. The concept of synonymy in zoology is reserved for two names at the same rank that refers to a taxon at that rank - for example, the name ''Papilio prorsa'' Linnaeus, 1758 is a junior synonym of ''Papilio levana'' Linnaeus, 1758, being names for different seasonal forms of the species now referred to as ''Araschnia lev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three-barbeled Catfish
The Heptapteridae, or three-barbeled catfishes, are a family of catfish that originate from the Americas. Most species are restricted to South America, but '' Imparfinis lineatus'', '' Nemuroglanis panamensis'' and '' Pimelodella chagresi'' are native to Panama, and ''Rhamdia'' species occur as far north as Mexico. The name Heptapteridae is derived from Greek, ''hepta'' meaning seven and ''pteron'' meaning fin. The diversity of this family is poorly known, and many species are yet to be described. So far, some 211 species have been described. This family is equivalent to the previously recognized Rhamdiinae, a subfamily of the family Pimelodidae. However, molecular evidence shows this family is a part of the superfamily Pimelodoidea along with the Pimelodidae, Pseudopimelodidae, and '' Conorhynchos''. The skin of these fish is usually naked (scaleless). They exhibit three pairs of barbels. They have a large adipose fin, and their caudal fin is deeply forked. However, no extern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhamdia Reddelli
The juil ciego or blindwhiskered catfish (''Rhamdia reddelli'') is a species of three-barbeled catfish endemic to Mexico. This species is troglobitic, inhabiting a certain stream that flows through a single cave system. Description Like other fish found exclusively in caves, the skin of ''R. reddelli'' lacks pigment. The fish also lacks eyes, instead having various sensory organs for taste, smell, and touch; these can help it to orient itself in the total darkness and locate food. It is a small fish up to long, with a flattened head, a long dorsal fin, and a deeply forked tail. The three barbels on the chin are long and packed with sensory cells. Distribution ''R. reddelli'' is known from a single cave system in Mexico through which flows an underground stream about long. The cave is near San Antonio Cañada, in the Sierra Madre de Oaxaca southeast of Mexico City. Ecology No living plants are present in this cave, so this fish is mostly reliant on the detritus of organic ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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