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Poecilia Velifera
''Poecilia velifera'', known as the Yucatan molly and also as the giant sailfin molly amongst aquarists, is a very large Livebearer that lives in coastal waters of the Yucatan peninsula. These live-bearer (Poeciliidae) fish are particularly well known for both the extreme size variation among males, and the sexual dimorphism between males and females in both body shape and behavior. It is outwardly similar to the sailfin molly, ''P. latipinna'', though larger overall and with a higher and longer dorsal fin in males. Full-grown fish are usually larger than 10 cm (4 in) and large females can reach almost twice this length, though especially captive-bred individuals grow only to the size of sailfin mollies. The dorsal fins are the most distinctive character for telling the species apart: Those of the Yucatan molly have nearly 20 fin rays, counting where the fin meets the back, whereas the sailfin molly has less than 15 (intermediate numbers may indicate hybrids). If the m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Tate Regan
Charles Tate Regan FRS (1 February 1878 – 12 January 1943) was a British ichthyologist, working mainly around the beginning of the 20th century. He did extensive work on fish classification schemes. Born in Sherborne, Dorset, he was educated at Derby School and Queens' College, Cambridge and in 1901 joined the staff of the Natural History Museum, where he became Keeper of Zoology, and later director of the entire museum, in which role he served from 1927 to 1938. Regan was elected Fellow of the Royal Society in 1917. Regan mentored a number of scientists, among them Ethelwynn Trewavas, who continued his work at the British Natural History Museum. Species Among the species he described is the Siamese fighting fish (''Betta splendens''). In turn, a number of fish species have been named ''regani'' in his honour: *A Thorny Catfish '' Anadoras regani'' (Steindachner, 1908) *The Dwarf Cichlid '' Apistogramma regani'' *'' Apogon regani'' *A Catfish '' Astroblepus regani'' * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Molly
''Poecilia sphenops'' is a species of fish, of the genus ''Poecilia'', known under the common name molly; to distinguish it from its congeners, it is sometimes called short-finned molly or common molly. They inhabit fresh water streams and coastal brackish and marine waters from Mexico to Colombia. The wild-type fishes are dull, silvery in color. The molly can produce fertile hybrids with many ''Poecilia'' species, most importantly the sailfin molly. The male mollies generally tend to be mildly aggressive. Mollies rank as one of the most popular feeder fish due to high growth rate, birth size, reproduction, and brood number. Biology Contrary to popular belief, this species of fish is actually a freshwater species, spending little time in brackish water before swimming back to their freshwater biotope. However, fish of the same species have been found in coastal sea waters, brackish swamps and freshwater streams, living and breeding. Mollies appear to be a hardy and highly adapt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Described In 1914
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Most fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in blending inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridisation, which include genetic and morphological differences, differing times of fertility, mating behaviors and cues, and physiological rejection of sperm cells or the developing embryo. Some act before fertilization and others after it. Similar barriers exist in plants, with differences in flowering tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poecilia
''Poecilia'' is a genus of fishes in the family Poeciliidae of the order Cyprinodontiformes. These livebearers are native to fresh, brackish and salt water in the Americas, and some species in the genus are euryhaline. A few have adapted to living in waters that contain high levels of toxic hydrogen sulfide ()Palacios, Arias-Rodriguez, Plath, Eifert, Lerp, Lamboj, Voelker, & Tobler (2013). The Rediscovery of a Long Described Species Reveals Additional Complexity in Speciation Patterns of Poeciliid Fishes in Sulfide Springs.' PLoS ONE 8(8): e71069. and a population of '' P. mexicana'' lives in caves (other populations of this species are surface-living). Some common and widespread species are often kept as aquarium fish, while other have very small ranges and are seriously threatened. All species in ''Poecilia'' are called mollies except for the Endler's livebearer (''P. wingei'') and the well-known guppy (''P. reticulata'') which have a distinctly different body shape from the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euryhaline
Euryhaline organisms are able to adapt to a wide range of salinities. An example of a euryhaline fish is the molly (''Poecilia sphenops'') which can live in fresh water, brackish water, or salt water. The green crab (''Carcinus maenas'') is an example of a euryhaline invertebrate that can live in salt and brackish water. Euryhaline organisms are commonly found in habitats such as estuaries and tide pools where the salinity changes regularly. However, some organisms are euryhaline because their life cycle involves migration between freshwater and marine environments, as is the case with salmon and eels. The opposite of euryhaline organisms are stenohaline ones, which can only survive within a narrow range of salinities. Most freshwater organisms are stenohaline, and will die in seawater, and similarly most marine organisms are stenohaline, and cannot live in fresh water. Osmoregulation Osmoregulation is the active process by which an organism maintains its level of water cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtropical
The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Geographical zone#Temperate zones, temperate zones of both hemispheres, they cover the middle latitudes from to approximately 35° north and south. The horse latitudes lie within this range. Subtropical climates are often characterized by hot summers and mild winters with infrequent frost. Most subtropical climates fall into two basic types: humid subtropical climate, humid subtropical (Köppen climate classification, Koppen climate Cfa), where rainfall is often concentrated in the warmest months, for example list of regions of China, Southeast China and the Southeastern United States, and Mediterranean climate, dry summer or Mediterranean climate (Köppen climate classification, Koppen climate Csa/Csb), where seasonal rainfall is concentrated in the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as ''Chlorella,'' ''Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and autotrophic (they generate food internally) and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the ''Charophyta'', a division of green algae which includes, for example, ''Spirogyra'' and stoneworts. No definition of algae is generally accepted. One definition is that algae "have chlorophyll ''a'' as their primary photosynthetic pigment and lack a sterile covering of cells around thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Danionin
The danionins are a group of small, minnow-type fish belonging to the family Cyprinidae. Members of this group are mostly in the genera ''Danio'', ''Devario'', and ''Rasbora''._They_are_primarily_native_to_the_s_...''._They_are_primarily_native_to_the_fresh_water">outheast_Asia,_as_well_as_southeast_China._A_single_species,_''R._gerlachi'',_is_only_known_from_an_old_Zoological_specimen">s_...''._They_are_primarily_native_to_the_fresh_waters_of_South_Asia.html" "title="fresh_water.html" ;"title="outheast Asia, as well as southeast China. A single species, ''R. gerlachi'', is only known from an old Zoological specimen">s ...''. They are primarily native to the fresh water">outheast Asia, as well as southeast China. A single species, ''R. gerlachi'', is only known from an old Zoological specimen">s ...''. They are primarily native to the fresh waters of South Asia">South and Southeast Asia, with fewer species in Africa. Many species are brightly coloured and are available as aquarium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetra
Terrestrial Trunked Radio (TETRA; formerly known as Trans-European Trunked Radio), a European standard for a trunked radio system, is a professional mobile radio and two-way transceiver specification. TETRA was specifically designed for use by government agencies, emergency services, (police forces, fire departments, ambulance) for public safety networks, rail transport staff for train radios, transport services and the military. TETRA is the European version of trunked radio, similar to Project 25. TETRA is a European Telecommunications Standards Institute (ETSI) standard, first version published 1995; it is mentioned by the European Radiocommunications Committee (ERC). Description TETRA uses time-division multiple access (TDMA) with four user channels on one radio carrier and 25 kHz spacing between carriers. Both point-to-point and point-to-multipoint transfer can be used. Digital data transmission is also included in the standard though at a low data rate. TETRA Mob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liter
The litre (international spelling) or liter (American English spelling) (SI symbols L and l, other symbol used: ℓ) is a metric unit of volume. It is equal to 1 cubic decimetre (dm3), 1000 cubic centimetres (cm3) or 0.001 cubic metre (m3). A cubic decimetre (or litre) occupies a volume of (see figure) and is thus equal to one-thousandth of a cubic metre. The original French metric system used the litre as a base unit. The word ''litre'' is derived from an older French unit, the '' litron'', whose name came from Byzantine Greek—where it was a unit of weight, not volume—via Late Medieval Latin, and which equalled approximately 0.831 litres. The litre was also used in several subsequent versions of the metric system and is accepted for use with the SI,Bureau International des Poids et M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Salt
Sea salt is salt that is produced by the evaporation of seawater. It is used as a seasoning in foods, cooking, cosmetics and for preserving food. It is also called bay salt, solar salt, or simply salt. Like mined rock salt, production of sea salt has been dated to prehistoric times. Composition Commercially available sea salts on the market today vary widely in their chemical composition. Although the principal component is sodium chloride, the remaining portion can range from less than 0.2 to 10% of other salts. These are mostly calcium, potassium, and magnesium salts of chloride and sulfate with substantially lesser amounts of many trace elements found in natural seawater. Though the composition of commercially available salt may vary, the ionic composition of natural saltwater is relatively constant. Historical production Sea salt is mentioned in the Vinaya Pitaka, a Buddhist scripture compiled in the mid-5th century BC. The principle of production is evaporation of the w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
