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Red-claw Crayfish
''Cherax quadricarinatus'' (known by several common names, including Australian red claw crayfish, Queensland red claw, redclaw, tropical blue crayfish, freshwater blueclaw crayfish) is an Australian freshwater crayfish. Distribution and ecology ''C. quadricarinatus'' is native to permanent freshwater streams, billabongs and lakes on the north coast of the Northern Territory, northeastern Queensland, and Papua New Guinea. Through translocation by humans, the range has spread down to southern Queensland and into the far north of Western Australia. ''C. quadricarinatus'' is considered an invasive species, and has established feral populations in South Africa, Mexico, Jamaica, Puerto Rico, Indonesia, Zambia, Malaysia and Singapore. This tropical crustacean is very tolerant of environmental changes, and is primarily a detritivore. Description The colour of ''C. quadricarinatus'' ranges from dark brown to blue-green. Their heads have four keels (as inferred by the specific name (zoo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eduard Von Martens
Eduard von Martens (18 April 1831 – 14 August 1904) also known as ''Carl'' or ''Karl Eduard von Martens'', was a German zoologist. Born in Stuttgart in 1831, von Martens attended university in University of Tübingen, Tübingen, where he graduated in 1855. He then moved to Berlin, where he would be based for the remainder of his career, both at the Zoological Museum of the Berlin University (from 1855) and, from 1859 on, at the . In 1860, he embarked on the ''Thetis'' expedition of the Prussian expedition to Eastern Asia. When the expedition returned to Europe in 1862, von Martens continued to travel around Maritime Southeast Asia for 15 months. He published the results of the "Thetis" expedition in two volumes, constituting the Zoologischer Theil of the "Preussische Expedition nach Ost-Asien." Vol. ii, consisting of 447 pages and 22 plates, contained a very full account of the land molluscs. Back in Berlin, von Martens was curator of the malacological and other invertebrate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Detritivore
Detritivores (also known as detrivores, detritophages, detritus feeders or detritus eaters) are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces). There are many kinds of invertebrates, vertebrates, and plants that eat detritus or carry out coprophagy. By doing so, all these detritivores contribute to decomposition and the nutrient cycles. Detritivores should be distinguished from other decomposers, such as many species of bacteria, fungi and protists, which are unable to ingest discrete lumps of matter. Instead, these other decomposers live by absorbing and metabolizing on a molecular scale (saprotrophic nutrition). The terms ''detritivore'' and ''decomposer'' are often used interchangeably, but they describe different organisms. Detritivores are usually arthropods and help in the process of remineralization. Detritivores perform the first stage of remineralization, by fragmenting the dead plant matter, allowing decomp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustaceans Described In 1868
Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthropods including decapods (shrimps, prawns, crabs, lobsters and crayfish), seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, opossum shrimps, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods (insects and entognathans) emerged deep in the Crustacean group, with the completed pan-group referred to as Pancrustacea. The three classes Cephalocarida, Branchiopoda and Remipedia are more closely related to the hexapods than they are to any of the other crustaceans ( oligostracans and multicrustaceans). The 67,000 described species range in size from ''Stygotantulus stocki'' at , to the Japanese spider crab with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Crustaceans Of Australia
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 always pota ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parastacidae
The Parastacidae are the family of freshwater crayfish found in the Southern Hemisphere. The family is a classic Gondwana-distributed taxon, with extant members in South America, Madagascar, Australia, New Zealand, and New Guinea, and extinct taxa also in Antarctica. Classification and phylogeny Parastacidae belongs to the superfamily Parastacoidea, the monotypic taxon which contains all crayfish in the Southern Hemisphere. Parastacoidea is the sister taxon to Astacoidea, which contains all crayfish of the Northern Hemisphere. Crayfish and lobsters together comprise the infraorder Astacidea, as shown in the simplified cladogram below: Distribution Three genera are found in Chile, '' Virilastacus'', '' Samastacus'' and '' Parastacus'', the last of which also occurs disjunctly in southern Brazil and Uruguay. There are no crayfish native to continental Africa, but seven species on Madagascar, all of the genus '' Astacoides''. Australasia is particularly rich in crayfish. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Maturity
Sexual maturity is the capability of an organism to reproduce. In humans, it is related to both puberty and adulthood. ''Puberty'' is the biological process of sexual maturation, while ''adulthood'', the condition of being socially recognized as an independent person capable of giving consent and taking responsibility, generally implies sexual maturity (certain disorders of sexual development notwithstanding), but depends on other criteria, defined by specific cultural expectations. Most multicellular organisms are unable to sexually reproduce at birth (animals) or germination (e.g. plants): depending on the species, it may be days, weeks, or years until they have developed enough to be able to do so; in addition, certain cues may trigger an organism to become sexually mature. These may be external, such as drought, or fire, that triggers sexual maturation of certain plants, or internal, such as percentage of body fat (certain animals). Internal cues are not to be confused ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Practical Fishkeeping
''Practical Fishkeeping'' (also known as ''PFK'') is a United Kingdom-based aquarium magazine. It is published every four weeks by Warners Publications Plc. The title covers the entire aquatic market from tropical freshwater and tropical marine fishkeeping throughout the year to small amounts of pond and coldwater fish coverage during the summer months. History and profile Originally called ''Pet Fish Monthly'', the title launched in April 1966. The title changed its name to ''Practical Fishkeeping'' in 1981. The magazine is edited by Nathan Hill, who took on the role as of January 2018. Regular contributing authors include, Nathan Hill, Julian Dignall, Ad Konings, Max Pedley, Ivan Mikolji, Keith Naitby, Chris Sergeant, Tim Smith, Heiko Bleher, Gabor Horvath, Steve Baker, Tristan Lougher, Dave Wolfenden, Bob Mehen and George Farmer. Former editors of the title include Steve Windsor, Nick Fletcher, Karen Youngs, Matt Clarke, Jeremy Gay and Angela Kenny. The headquarters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pereiopod
The anatomy of a decapod consists of 20 body segments grouped into two main body parts: the cephalothorax and the pleon (abdomen). Each segment – often called a somite – may possess one pair of appendages, although in various groups these may be reduced or missing. Cephalothorax Head # antennules # antennae # mandibles # first maxillae # second maxillae The head also bears the (usually stalked) compound eyes. The distal portion of a mandible or maxilla which has a sensory function is known as a palp. Thorax / pereon #first maxillipeds #second maxillipeds #third maxillipeds #first pereiopods #second pereiopods #third pereiopods #fourth pereiopods #fifth pereiopods Maxillipeds are appendages modified to function as mouthparts. Particularly in the less advanced decapods, these can be very similar to the pereiopods. Pereiopods are primarily walking legs and are also used for gathering food. They are also the ten legs from which decapods take their name. Those pereiopods which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spermatophore
A spermatophore, from Ancient Greek σπέρμα (''spérma''), meaning "seed", and -φόρος (''-phóros''), meaning "bearing", or sperm ampulla is a capsule or mass containing spermatozoa created by males of various animal species, especially salamanders and arthropods, and transferred in entirety to the female's ovipore during reproduction. Spermatophores may additionally contain nourishment for the female, in which case it is called a nuptial gift, as in the instance of bush crickets. In the case of the toxic moth '' Utetheisa ornatrix'', the spermatophore includes sperm, nutrients, and pyrrolizidine alkaloids which prevent predation because it is poisonous to most organisms. However, in some species such as the Edith's checkerspot butterfly, the "gift" provides little nutrient value. The weight of the spermatophore transferred at mating has little effect on female reproductive output. Arthropods Spermatophores are the norm in arachnid Arachnids are arthro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fertilization
Fertilisation or fertilization (see American and British English spelling differences#-ise, -ize (-isation, -ization), spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a zygote and initiate its development into a new individual organism or offspring. While processes such as insemination or pollination, which happen before the fusion of gametes, are also sometimes informally referred to as fertilisation, these are technically separate processes. The cycle of fertilisation and development of new individuals is called sexual reproduction. During double fertilisation in angiosperms, the haploid male gamete combines with two haploid polar nuclei to form a triploid primary endosperm nucleus by the process of vegetative fertilisation. History In antiquity, Aristotle conceived the formation of new individuals through fusion of male and female fluids, with form and function emerging gradually, in a mode c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olive (color)
Olive is a dark yellowish-green color, like that of unripe or green olives. As a color word in the English language, it appears in late Middle English. Variations Olivine Olivine is the typical color of the mineral olivine. The first recorded use of ''olivine'' as a color name in English was in 1912. Olive drab Olive drab is variously described as a "A brownish-green colour" (''Oxford English Dictionary'');" Olive Drab, N." Oxford English Dictionary, Oxford UP, July 2023. "a shade of greenish-brown" (''Webster's New World Dictionary''); "a dark gray-green" (''MacMillan English dictionary''); "a grayish olive to dark olive brown or olive gray" (''American Heritage Dictionary''); or "A dull but fairly strong gray-green color" (''Collins English Dictionary''). It is widely used as a camouflage color for uniforms and equipment in the armed forces. The first recorded use of ''olive drab'' as a color name in English was in 1892. Drab is an older color name, from the mid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Government Of Queensland
The Queensland Government is the state government of Queensland, Australia, a parliamentary constitutional monarchy. Government is formed by the party or coalition that has gained a majority in the state Legislative Assembly, with the governor officially appointmenting office-holders. The first government of Queensland was formed in 1859 when Queensland separated from New South Wales under the state constitution. Since federation in 1901, Queensland has been a state of Australia, with the Constitution of Australia regulating its relationship with the federal government. Queensland's system of government is influenced by the Westminster system and Australia's federal system of government. Executive acts are given legal force through the actions of the governor of Queensland (the representative of the monarch, Charles III), although the governor in practice performs only ceremonial duties, with de facto executive power lying with the Cabinet. The Cabinet is the government' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
