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Euastacus Jagabar
''Euastacus'' is a genus of fresh water, freshwater crayfish known as "spiny crayfish". They are found in the south-east of the Australian mainland, along with another genus of crayfish, ''Cherax''. Both genera are members of the family Parastacidae, a family of freshwater crayfish restricted to the Southern Hemisphere. ''Euastacus'' crayfish are distinguished from the smooth-shelled ''Cherax'' species by the short robust spikes on their claws and carapace, and frequently, their larger size. Many ''Euastacus'' species grow to a relatively large size, with the Murray crayfish, Murray River crayfish (''Euastacus armatus'') being the second largest freshwater crayfish species in the world. (The largest freshwater crayfish in the world is the Tasmanian giant freshwater crayfish (''Astacopsis gouldi''), found on the Australian island of Tasmania, and the genus ''Astacopsis'' is now known to be a very closely related sister genus to ''Euastacus''.) The genera ''Cherax'' and ''Euastac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellen Clark
Ellen Clark (1915–1988) was an Australian carcinologist and naturalist, whose work focused on crustaceans and ants Clark studied, named, described and published many of the Australian freshwater crayfish species. By 1939, she was reported to have identified more than half the known species of Australian crayfish. She conducted research about blood groups in crustaceans and made a significant contribution to the study of crayfish genera. She was the first woman to publish in the ''Memoirs of the National Museum of Victoria''. Ellen Clark's crayfish, ''Euastacus clarkae'', was named after Clark in recognition of her pioneering parastacid studies. Clark's work has had a lasting legacy and is still being debated in scientific papers. References Australian scientists 1915 births 1988 deaths Women naturalists 20th-century Australian women {{Australia-scientist-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drainage Basin
A drainage basin is an area of land in which all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, the drainage divide, made up of a succession of elevated features, such as ridges and hills. A basin may consist of smaller basins that merge at river confluences, forming a hierarchical pattern. Other terms for a drainage basin are catchment area, catchment basin, drainage area, river basin, water basin, and impluvium. In North America, they are commonly called a watershed, though in other English-speaking places, " watershed" is used only in its original sense, that of the drainage divide line. A drainage basin's boundaries are determined by watershed delineation, a common task in environmental engineering and science. In a closed drainage basin, or endorheic basin, rather than flowing to the ocean, water converges toward the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euastacus Australasiensis
''Euastacus'' is a genus of freshwater crayfish known as "spiny crayfish". They are found in the south-east of the Australian mainland, along with another genus of crayfish, ''Cherax''. Both genera are members of the family Parastacidae, a family of freshwater crayfish restricted to the Southern Hemisphere. ''Euastacus'' crayfish are distinguished from the smooth-shelled ''Cherax'' species by the short robust spikes on their claws and carapace, and frequently, their larger size. Many ''Euastacus'' species grow to a relatively large size, with the Murray River crayfish (''Euastacus armatus'') being the second largest freshwater crayfish species in the world. (The largest freshwater crayfish in the world is the Tasmanian giant freshwater crayfish (''Astacopsis gouldi''), found on the Australian island of Tasmania, and the genus ''Astacopsis'' is now known to be a very closely related sister genus to ''Euastacus''.) The genera ''Cherax'' and ''Euastacus'' continue a trend prese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Status Iucn DD Icon
Status (Latin plural: ''statūs''), is a state, condition, or situation, and may refer to: * Status (law) ** Legal status, in law ** Political status, in international law ** Small entity status, in patent law ** Status conference ** Status crime * Marital status * Observer status, in international organizations * Senior status * Social status, in sociology ** Achieved status ** Ascribed status ** Master status ** Socioeconomic status ** Sociometric status ** Status attainment ** Status offense ** Status shift * Status constructus, a noun form * Status match, in frequent-flyer loyalty programs * Status quo * Status symbol Arts, entertainment, and media * ''Status'', a magazine edited by Igor Cassini * ''Status'', a news site by Oliver Darcy * Recurring status, in acting * Status effect, in gaming Computing * Exit status, in computer science * HTTP status codes, a type of server response on the web * Process state, also called process status * Status bar, in user interfac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euastacus Armatus
The Murray crayfish, ''Euastacus armatus'', is a species of freshwater crayfish endemic to Australia that belongs to the family Parastacidae. The Murray crayfish has the largest geographic range of any of the ''Euastacus'' crayfish in Australia, being found in the Murray and Murrumbidgee Rivers as well as many of their tributaries. Murray crayfish are also known as "Murray River crayfish", "Murray crays", "freshwater crays", "spiny freshwater crays", "spinies" and in the Wagga Wagga region of southern New South Wales they are simply known as "lobsters". Today adults commonly grow to in length. In the past however they have been reliably recorded at significantly larger lengths and up to in weight; the Murray crayfish is considered the second largest freshwater crayfish species in the world after the Tasmanian giant freshwater crayfish. Murray crayfish have large white claws and a dark olive/grey/black carapace, all of which are covered in short robust spikes. In small individ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Deficient
A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessarily indicate that the species has not been extensively studied, but it usually indicates that little or no information is available on the abundance and distribution of the species. It can also indicate uncertainty about the taxonomic classification of an organism; for example, the IUCN classifies the orca as "data deficient" because of the likelihood that two or more types of the whale are separate species. The IUCN recommends that care be taken to avoid classing species as "data deficient" when the absence of records may indicate dangerously low abundance: "If the range of a taxon is suspected to be relatively circumscribed, if a considerable period of time has elapsed since the last record of the taxon, threatened status may well be ju ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Least Concern
A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wild. They do not qualify as threatened, near threatened, or (before 2001) conservation dependent. Species cannot be assigned the "Least Concern" category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, assessment of its risk of extinction based on its distribution or population status. Evaluation Since 2001 the category has had the abbreviation "LC", following the IUCN 2001 Categories & Criteria (version 3.1). Before 2001 "least concern" was a subcategory of the " Lower Risk" category and assigned the code "LR/lc" or lc. Around 20% of least concern taxa (3261 of 15,636) in the IUCN database still use the code "LR/lc", which indicates they have not been re- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near Threatened
A near-threatened species is a species which has been Conservation status, categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to Endangered species, endangerment in the near future, but it does not currently qualify for the threatened status. The IUCN notes the importance of reevaluating near-threatened taxon, taxa at appropriate intervals. The rationale used for near-threatened taxa usually includes the criteria of Vulnerable species, 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 Dependen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vulnerable Species
A vulnerable species is a species which has been Conservation status, categorized by the International Union for Conservation of Nature as being threatened species, threatened with extinction unless the circumstances that are threatened species, threatening its survival and reproduction improve. Vulnerability is mainly caused by habitat loss or destruction of the species' home. Vulnerable habitat or species are monitored and can become increasingly threatened. Some species listed as "vulnerable" may be common in captivity (animal), captivity, an example being the military macaw. In 2012 there were 5,196 animals and 6,789 plants classified as vulnerable, compared with 2,815 and 3,222, respectively, in 1998. Practices such as cryoconservation of animal genetic resources have been enforced in efforts to conserve vulnerable breeds of livestock specifically. Criteria The International Union for Conservation of Nature uses several criteria to enter species in this category. A taxon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endangered Species
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, invasive species, and climate change. The International Union for Conservation of Nature (IUCN) Red List lists the global conservation status of many species, and various other agencies assess the status of species within particular areas. Many nations have laws that protect conservation-reliant species which, for example, forbid hunting, restrict land development, or create protected areas. Some endangered species are the target of extensive conservation efforts such as captive breeding and habitat restoration. Human activity is a significant cause in causing some species to become endangered. Conservation status The conservation status of a species indicates the likelihood that it will become extinct. Multiple factors are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critically Endangered
An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of the 157,190 species currently on the IUCN Red List, 9,760 of those are listed as critically endangered, with 1,302 being possibly extinct and 67 possibly extinct in the wild. The IUCN Red List provides the public with information regarding the conservation status of animal, fungi, and plant species. It divides various species into seven different categories of conservation that are based on habitat range, population size, habitat, threats, etc. Each category represents a different level of global extinction risk. Species that are considered to be critically endangered are placed within the "Threatened" category. As the IUCN Red List does not consider a species extinct until extensive targeted surveys have been conducted, species that a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 an inventory of the global conservation status and extinction risk of biological species. A series of Regional Red Lists, which assess the risk of extinction to species within a political management unit, are also produced by countries and organizations. The goals of the Red List are to provide scientifically based information on the status of species and subspecies at a global level, to draw attention to the magnitude and importance of threatened biodiversity, to influence national and international policy and decision-making, and to provide information to guide actions to conserve biological diversity. Major species assessors include BirdLife International, the Institute of Zoology (the research division of the Zoological Society of London), the World Conservation Monitoring Centre, and many Specialist Groups w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
