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Heliotrygon
The round rays (''Heliotrygon'') is a genus of freshwater stingrays in the family Potamotrygonidae. The genus is endemic to the Amazon basin in South America. Despite being discovered decades earlier, the genus was only scientifically described in 2011.de Carvalho, M.R. and N.R. Lovejoy (2011). Morphology and phylogenetic relationships of a remarkable new genus and two new species of Neotropical freshwater stingrays from the Amazon basin (Chondrichthyes: Potamotrygonidae). Zootaxa 2776: 13-48. They mainly live in deep river channels, but approach the shore at night to feed on fish. Their discs are very circular in shape (including the snout), and they have tiny eyes and a relatively short tail with an essentially harmless, vestigial stinger (sometimes even lacking). The largest confirmed disc width is , but there are reports of individuals where it was . Both species are greyish or brownish above, but while ''H. gomesi'' is overall plain without distinct markings, ''H. rosai'' ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliotrygon Gomesi
''Heliotrygon gomesi'', the Gomes's round ray or China ray, is a species of freshwater stingray native to the western Amazon basin in South America, specifically Brazil.de Carvalho, M.R. and N.R. Lovejoy, 2011. Morphology and phylogenetic relationships of a remarkable new genus and two new species of Neotropical freshwater stingrays from the Amazon basin (Chondrichthyes: Potamotrygonidae). Zootaxa 2776:13-48. It is the type species of its genus. It spends the day in deep river channels, but moves closer to the shore at night to feed. Taxonomy ''H. gomesi'' was first discovered in Rio Jamari, Brazil, and described by Marcelo Rodrigues de Carvalho and Nathan R. Lovejoy in 2011. The genus name, ''Heliotrygon,'' is derived from the Greek word 'helios,'' meaning sun, and refers to the ray's circular body that radiates outward. This species is named ''gomesi'' in honor of Ulisses L. Gomes and his pioneering research on elasmobranchs. Gomes' round ray is a member of the family Po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamotrygonidae
River stingrays or freshwater stingrays are Neotropical freshwater fishes of the family (biology), family Potamotrygonidae in the Order (biology), order Myliobatiformes, one of the four orders of Batoidea, batoids, cartilaginous fishes related to sharks. They are found in rivers in tropical and subtropical South America (freshwater stingrays in Africa, Asia and Australia are in another family, Dasyatidae). A single marine genus, ''Styracura'', of the tropical West Atlantic and East Pacific are also part of Potamotrygonidae. They are generally brownish, greyish or black, often with a mottled, speckled or spotted pattern, have disc widths ranging from and venomous tail stingers. River stingrays feed on a wide range of smaller animals and the females give birth to live young. There are more than 35 species in five genera. Distribution and habitat They are native to tropical and subtropical northern, central and eastern South America, living in rivers that drain into the Caribbean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliotrygon Rosai
''Heliotrygon rosai'', the Rosa's round ray, is a species of freshwater fish in the family Potamotrygonidae. It is native to the Amazon basin (Marajó to Peru) in South America.de Carvalho, M.R. & Lovejoy, N.R. (2011): Morphology and phylogenetic relationships of a remarkable new genus and two new species of Neotropical freshwater stingrays from the Amazon basin (Chondrichthyes: Potamotrygonidae). ''Zootaxa, 2776: 13-48.'' Its maximum disc width is and the stinger is greatly reduced, rendering it virtually harmless. It has not been evaluated by the IUCN red list The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol .... References Potamotrygonidae Freshwater fish of Brazil Freshwater fish of Peru Fish of the Amazon basin Fish described in 2011 {{chondrichthyes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animalia
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestigial
Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on comparison with homologous features in related species. The emergence of vestigiality occurs by normal evolutionary processes, typically by loss of function of a feature that is no longer subject to positive selection pressures when it loses its value in a changing environment. The feature may be selected against more urgently when its function becomes definitively harmful, but if the lack of the feature provides no advantage, and its presence provides no disadvantage, the feature may not be phased out by natural selection and persist across species. Examples of vestigial structures (also called degenerate, atrophied, or rudimentary organs) are the loss of functional wings in island-dwelling birds; the human vomeronasal organ; and the hin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Fish Of Peru
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. Fresh water is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Fish Of Brazil
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. Fresh water is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermiculated
Vermiculation is a surface pattern of dense but irregular lines, so called from the Latin ''vermiculus'' meaning "little worm" because the shapes resemble worms, worm-casts, or worm tracks in mud or wet sand. The word may be used in a number of contexts for patterns that have little in common. The adjective vermiculated is more often used than the noun. Vermiculation naturally occurs in patterns on a wide variety of species, for example in the feathers of certain birds, for which it may provide either camouflageSee, e.g., Iain Campbell, Sam Woods, Nick Leseberg, ''Birds of Australia: A Photographic Guide'' (2014), p. 110. or decoration. Several species are named after this trait, either in English or by the Latin ''vermicularis''. It also appears in architecture as a form of rustication where the stone is cut with a pattern of wandering lines. In metalwork, vermiculation is used to form a type of background found in Romanesque enamels, especially on chasse reliquary caske ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CSIRO
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) is an Australian Government The Australian Government, also known as the Commonwealth Government, is the national government of Australia, a federal parliamentary constitutional monarchy. Like other Westminster-style systems of government, the Australian Government ... agency responsible for scientific research. CSIRO works with leading organisations around the world. From its headquarters in Canberra, CSIRO maintains more than 50 sites across Australia and in France, Chile and the United States, employing about 5,500 people. Federally funded scientific research began in Australia years ago. The Advisory Council of Science and Industry was established in 1916 but was hampered by insufficient available finance. In 1926 the research effort was reinvigorated by establishment of the Council for Scientific and Industrial Research (CSIR), which strengthened national science leadership and increased ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amazon Basin
The Amazon basin is the part of South America drained by the Amazon River and its tributaries. The Amazon drainage basin covers an area of about , or about 35.5 percent of the South American continent. It is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, Suriname, and Venezuela. Most of the basin is covered by the Amazon rainforest, also known as Amazonia. With a area of dense tropical forest, this is the largest rainforest in the world. Geography The Amazon River begins in the Andes Mountains at the west of the basin with its main tributary the Marañón River and Apurimac River in Peru. The highest point in the watershed of the Amazon is the second biggest peak of Yerupajá at . With a length of about before it drains into the Atlantic Ocean, it is one of the two longest rivers in the world. A team of scientists has claimed that the Amazon is longer than the Nile, but debate about its exact length continues. The Amazon system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chordata
A chordate () is an animal of the phylum Chordata (). All chordates possess, at some point during their larval or adult stages, five synapomorphies, or primary physical characteristics, that distinguish them from all the other taxa. These five synapomorphies include a notochord, dorsal hollow nerve cord, endostyle or thyroid, pharyngeal slits, and a post-anal tail. The name “chordate” comes from the first of these synapomorphies, the notochord, which plays a significant role in chordate structure and movement. Chordates are also Bilateral symmetry, bilaterally symmetric, have a coelom, possess a circulatory system, and exhibit Metameric, metameric segmentation. In addition to the morphological characteristics used to define chordates, analysis of genome sequences has identified two conserved signature indels (CSIs) in their proteins: cyclophilin-like protein and mitochondrial inner membrane protease ATP23, which are exclusively shared by all vertebrates, tunicates and cep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic
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] |
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