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Poeciliopsis Prolifica
''Poeciliopsis prolifica'', or the blackstripe livebearer, is a species of small freshwater fish in the family Poeciliidae. It is endemic to Mexico. It is a viviparous species and the female can have several clutches of young developing internally at the same time, hence the specific name ''prolifica'', from the Latin ''proles'', "offspring" and ''ferax'', "rich, fruitful" in reference to the great number of young produced. Description ''Poeciliopsis prolifica'' is a small, slender silvery fish growing to a maximum length of about for males and for females. Adult males can be told from females by the presence of a gonopodium, an extended rod-shaped anal fin that acts as an intromittent organ to introduce sperm into the female during mating. Distribution and habitat The species is endemic to Mexico where it is only found on the eastern side of the Gulf of California, between the states of Sonora and Nayarit. It is a shallow-water, freshwater fish, tolerant of brackish water and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Rush Miller
Robert Rush Miller (April 23, 1916 – February 10, 2003) was an important figure in American ichthyology and Conservation movement, conservation from 1940 to the 1990s. He was born in Colorado Springs, earned his bachelor's degree at University of California, Berkeley in 1938, a master's degree at the University of Michigan in 1943, and a doctorate, Ph.D. at the University of Michigan in 1944. He received tenure at the University of Michigan in 1954. Together with W. L. Minckley, he discovered a new species of platyfish, ''Xiphophorus gordoni'', that they named in honor of Dr Myron Gordon (biologist), Myron Gordon. He served as the ichthyological editor of ''Copeia'' from 1950 to 1955. Fish described * ''Chortiheros wesseli'' R. R. Miller 1996 - Cichlid * ''Cualac tessellatus'' R. R. Miller 1956 - (Checkered Pupfish) * ''Cyprinodon albivelis'' Wendell L. Minckley, W. L. Minckley & R. R. Miller, 2002 (Whitefin pupfish) * ''Cyprinodon alvarezi'' R. R. Miller, 1976 (Potosi pupfis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mangrove
A mangrove is a shrub or tree that grows mainly in coastal saline water, saline or brackish water. Mangroves grow in an equatorial climate, typically along coastlines and tidal rivers. They have particular adaptations to take in extra oxygen and remove salt, allowing them to tolerate conditions that kill most plants. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse due to convergent evolution in several plant families. They occur worldwide in the tropics and subtropics and even some temperate coastal areas, mainly between latitudes 30° N and 30° S, with the greatest mangrove area within 5° of the equator. Mangrove plant families first appeared during the Late Cretaceous to Paleocene epochs and became widely distributed in part due to the plate tectonics, movement of tectonic plates. The oldest known fossils of Nypa fruticans, mangrove palm date to 75 million years ago. Mangroves are salt-tolerant ... [...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. The term excludes seawater and brackish water, but 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. Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of vascular plants and most insects, amphibians, reptiles, mammals and birds need fresh water to survive. Fresh water is the water resource that is of the most and immediate use to humans. Fresh water is not alway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic Fish Of Mexico
Endemism is the state of a species being found only 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 also be referred to as an ''endemism'' or, in scientific literature, as an ''endemite''. Similarly, many species found in the Western ghats of India are examples of endemism. Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism is also of interest in evolutionary biology, because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area or becomi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poeciliopsis
''Poeciliopsis'' is a genus of poeciliid fishes that primarily are native to Mexico and Central America. The only exceptions are ''P. turrubarensis'' where the range extends into Colombia, and ''P. occidentalis'' where the range extends into Arizona and New Mexico. Species There are currently 24 recognized species in this genus: * '' Poeciliopsis baenschi'' ( M. K. Meyer, Radda, Riehl & Feichtinger, 1986) (Golden livebearer) * '' Poeciliopsis balsas'' ( C. L. Hubbs, 1926) (Balsas livebearer) * '' Poeciliopsis catemaco'' ( R. R. Miller, 1975) (Catemaco livebearer) * '' Poeciliopsis elongata'' ( Günther, 1866) (Elongate toothcarp) * '' Poeciliopsis fasciata'' ( Meek, 1904) (San Jeronimo livebearer) * '' Poeciliopsis gracilis'' ( Heckel, 1848) (Porthole livebearer) * '' Poeciliopsis hnilickai'' ( M. K. Meyer & Vogel, 1981) (Upper Grijalva livebearer) * '' Poeciliopsis infans'' ( Woolman, 1894) (Lerma livebearer) * '' Poeciliopsis latidens'' ( Garman, 1895) (Lowland livebearer) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near-threatened Species
A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to endangerment in the near future, but it does not currently qualify for the threatened status. The IUCN notes the importance of reevaluating near-threatened taxa at appropriate intervals. The rationale used for near-threatened taxa usually includes the criteria of vulnerable which are plausible or nearly met, such as reduction in numbers or range. Those designated since 2001 that depend on conservation efforts to not become threatened are no longer separately considered conservation-dependent species. IUCN Categories and Criteria version 2.3 Before 2001, the IUCN used the version 2.3 Categories and Criteria to assign conservation status, which included a separate category for conservation-dependent species ("Conservation Dependent", LR/cd). With this category system, Near Threatened and Con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union For Conservation Of Nature
The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status of the natural world and the measures needed to safeguard it. It is involved in data gathering and analysis, research, field projects, advocacy, and education. IUCN's mission is to "influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. IUCN does not itself aim to mobilize the public in support of nature conservation. It tries to influence the actions of governments, business and other stakeholders by providing information and advice and through building partners ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ovary
The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/ oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are endocrine glands, secreting various hormones that play a role in the menstrual cycle and fertility. The ovary progresses through many stages beginning in the prenatal period through menopause. Structure Each ovary is whitish in color and located alongside the lateral wall of the uterus in a region called the ovarian fossa. The ovarian fossa is the region that is bounded by the external iliac artery and in front of the ureter and the internal iliac artery. This area is about 4 cm x 3 cm x 2 cm in size.Daftary, Shirish; Chakravarti, Sudip (2011). Manual of Obstetrics, 3rd Edition. Elsevier. pp. 1-16. . The ovaries are surrounded by a capsule, and have an outer cortex and an inner medulla. The capsule is of dense connect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clutch (eggs)
A clutch of eggs is the group of eggs produced by birds, amphibians, or reptiles, often at a single time, particularly those laid in a nest. In birds, destruction of a clutch by predators (or removal by humans, for example the California condor breeding program) results in ''double-clutching''. The technique is used to double the production of a species' eggs, in the California condor case, specifically to increase population size. Size Clutch size differs greatly between species, sometimes even within the same genus. It may also differ within the same species due to many factors including habitat, health, nutrition, predation pressures, and time of year. Clutch size variation can also reflect variation in optimal reproduction effort. In birds, clutch size can vary within a species due to various features (age and health of laying female, ability of male to supply food, and abundance of prey), while some species are determinant layers, laying a species-specific number of egg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pericardium
The pericardium (: pericardia), also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong inelastic connective tissue (fibrous pericardium), and an inner layer made of serous membrane (serous pericardium). It encloses the pericardial cavity, which contains pericardial fluid, and defines the middle mediastinum. It separates the heart from interference of other structures, protects it against infection and blunt trauma, and lubricates the heart's movements. The English name originates from the Ancient Greek prefix ''peri-'' (περί) 'around' and the suffix ''-cardion'' (κάρδιον) 'heart'. Anatomy The pericardium is a tough fibroelastic sac which covers the heart from all sides except at the cardiac root (where the great vessels join the heart) and the bottom (where only the serous pericardium exists to cover the upper surface of the central tendon of diaphragm). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zooplankton
Zooplankton are the heterotrophic component of the planktonic community (the " zoo-" prefix comes from ), having to consume other organisms to thrive. Plankton are aquatic organisms that are unable to swim effectively against currents. Consequently, they drift or are carried along by currents in the ocean, or by currents in seas, lakes or rivers. Zooplankton can be contrasted with phytoplankton (cyanobacteria and microalgae), which are the plant-like component of the plankton community (the " phyto-" prefix comes from , although taxonomically ''not'' plants). Zooplankton are heterotrophic (other-feeding), whereas phytoplankton are autotrophic (self-feeding), often generating biological energy and macromolecules through chlorophyllic carbon fixation using sunlightin other words, zooplankton cannot manufacture their own food, while phytoplankton can. As a result, zooplankton must acquire nutrients by feeding on other organisms such as phytoplankton, which are generally smaller t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Detritus
In biology, detritus ( or ) is organic matter made up of the decomposition, decomposing remains of organisms and plants, and also of feces. Detritus usually hosts communities of microorganisms that colonize and decomposition, decompose (Remineralisation, remineralise) it. Such microorganisms may be decomposers, detritivores, or coprophages. In terrestrial ecosystems detritus is present as plant litter and other organic matter that is intermixed with soil, known as soil organic matter. The detritus of aquatic ecosystems is organic substances suspended in the water and accumulated in depositions on the floor of the body of water; when this floor is a seabed, such a deposition is called marine snow. Theory The remains of decaying plants or animals, or their tissue parts, and feces gradually lose their form due to physical processes and the action of decomposers, including grazers, bacteria, and fungi. Decomposition, the process by which organic matter is decomposed, occurs in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
