Crustaceans (Crustacea) are a very large group of arthropods An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the Phylum Arthropoda (from Greek ἄρθρον arthron, "joint", and ποδός podos "foot", which together mean "jointed feet"), and include the insects, arachnids, crustaceans, and, usually treated as a subphylum In life, a subphylum is a taxonomic rank intermediate between phylum and superclass. The rank of subdivision in plants and fungi is equivalent to subphylum [1]. The group comprises almost 52,000 described species There are quite a lot of definitions of what kind of unit a species is . A common definition is that of a group of organisms capable of interbreeding and producing fertile offspring of both genders, and separated from other such groups with which interbreeding does not (normally) happen. Other definitions may focus on similarity of DNA or [2], although the number of undescribed species may be 10–100 times higher [3]. They include various familiar animals, such as crabs True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax. Other animals, such as hermit crabs, king crabs, porcelain crabs, horseshoe crabs and crab lice, are not true crabs, lobsters Clawed lobsters comprise a family of large marine crustaceans. Lobsters are economically important as seafood, forming the basis of a global industry that nets more than US$1 billion annually, crayfish Crayfish, crawfish, or crawdads — members of the superfamilies Astacoidea and Parastacoidea — are freshwater crustaceans resembling small lobsters, to which they are related. They breathe through feather-like gills and are found in bodies of water that do not freeze to the bottom; they are also mostly found in brooks and streams where there is, shrimp Shrimp are swimming, decapod crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Adult shrimp are filter feeding benthic animals living close to the bottom. They can live in schools and can swim rapidly backwards. Shrimp are an important food source for larger animals from fish to whales, krill Krill is a shrimp-like marine invertebrate animal. These small crustaceans are important organisms of the zooplankton, particularly as food for baleen whales, manta rays, whale sharks, crabeater seals, other seals, and a few seabird species that feed almost exclusively on them. Another name is euphausiids, after their taxonomic order Euphausiacea and barnacles A barnacle is a type of arthropod belonging to infraclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile suspension feeders, and have two nektonic larval stages. Around 1,220 barnacle. The majority of them are aquatic, living in either marine Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology. As a noun it can be a term for a certain kind of navy, or those enlisted in such a navy or fresh water Freshwater or fresh water is naturally occurring water on the Earth's surface in bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Freshwater is characterized by having low concentrations of dissolved salts and other total dissolved solids. The term specifically excludes seawater and environments, but a few groups have adapted Adaptation is the process whereby a population becomes better suited to its habitat. This process takes place over many generations, and is one of the basic phenomena of biology to life on land, such as terrestrial crabs Gecarcinidae is a family of true crabs that are adapted for terrestrial existence, commonly known as land crabs. Similar to all other crabs, land crabs possess a series of gills. In addition, the part of the carapace covering the gills is inflated and equipped with blood vessels. These organs extract oxygen from the air, analogous to the, terrestrial hermit crabs The genus Coenobita contains about thirteen species of terrestrial hermit crabs. They are able to live on land because of their modified gills, although they still require a warm, humid environment. They can live several miles from water in moist forests and jungles and woodlice A woodlouse is a crustacean with a rigid, segmented, long exoskeleton and fourteen jointed limbs. Woodlice form the suborder Oniscidea within the order Isopoda, with over 3,000 known species. Crustaceans are among the most successful animals, and are as abundant in the oceans as insects are on land. The majority of crustaceans are also motile Motility is a biological term which refers to the ability to move spontaneously and actively, consuming energy in the process. Most animals are motile but the term applies to both single-celled and multicellular organisms. Motile marine animals are commonly called free-swimming. The opposite of motility is sessility, moving about independently, although a few taxonomic units are parasitic Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the host and live attached to their hosts (including sea lice There is reported concern that sea lice flourishing on salmon farms can spread to nearby wild juvenile salmon and devastate these populations. Sea trout populations in recent years have seriously declined due to infestation by sea lice from salmon farms. Several scientific studies have proven that caged farmed salmon harbours lice to a degree that, fish lice Branchiura, commonly called carp lice or fish lice are a group of parasitic crustaceans of uncertain position within the Maxillopoda. Although they are thought to be primitive forms, they have no fossil record. Almost all are ectoparasites on fish, with a few exceptions living on amphibians, whale lice, tongue worms The Pentastomida are a group of parasitic invertebrates commonly known as tongue worms due to the resemblance of the species of the genus Linguatula to a vertebrate tongue, and Cymothoa exigua, all of which may be referred to as "crustacean lice"), and adult barnacles live a sessile In zoology, sessility is a characteristic of animals which are not able to move about. They are usually permanently attached to a solid substrate of some kind, such as a rock, or the hull of a ship in the case of barnacles. Corals lay down their own substrate life—they are attached headfirst to the substrate and cannot move independently. Although most crustaceans are small, their morphology varies greatly and they include both the largest arthropod in the world — the 13 kg (29 lb) Tasmanian giant crab — and the smallest — the 0.1 mm (0.004 in) long Stygotantulus stocki [4].
The scientific study of these crustaceans is known as carcinology. Other names for carcinology are malacostracology, crustaceology and crustalogy, and a scientist A scientist, in the broadest sense, is any person who engages in a systematic activity to acquire knowledge or an individual that engages in such practices and traditions that are linked to schools of thought or philosophy. In a more restricted sense, a scientist is an individual who uses the scientific method. The person may be an expert in one who works in carcinology is a carcinologist, crustaceologist or crustalogist.
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In the animal kingdom, what is the woodlouse: an insect or a crustacean ? 4. In the 1997 film, which actor starred as Austin Powers, International Man of ...
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Washington - An international team of scientists has discovered two tiny worms much smaller than a rice grain and a strange . crustacean. that has no eyes and poisonous fangs, among several new species of marine life found in an underwater ...
