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Maxillopod
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, 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 emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans ( Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branchiura
The family Argulidae, whose members are commonly known as carp lice or fish lice, are parasitic crustaceans in the class Ichthyostraca. It is the only family in the monotypic subclass Branchiura and the order Arguloida, although a second family, Dipteropeltidae, has been proposed. Although they are thought to be primitive forms, they have no fossil record. Taxonomy Branchiurans were once thought to be copepods but are now recognised as a separate subclass due to their distinct morphological characteristics.Alan P. Covich, ... D. Christopher Rogers, in Ecology and Classification of North American Freshwater Invertebrates (Third Edition), 2010 There are approximately 170 species in four genera recognised in the family Branchiura. The centres of diversity are the Afrotropical and Neotropical realms. Description Branchiurans have a flattened, oval body, which is almost entirely covered by a broad, oval carapace, four pairs of swimming legs, a pair of anterior compound eyes, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multicrustacea
The clade Multicrustacea constitutes the largest superclass of crustaceans, containing approximately four-fifths of all described crustacean species, including crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, barnacles, copepods, amphipods, mantis shrimp and others. The largest branch of multicrustacea is the class Malacostraca (see below). Classification Superclass Multicrustacea Regier, Shultz, Zwick, Hussey, Ball, Wetzer, Martin & Cunningham, 2010 * Family Priscansermarinidae Newman, 2004 * Class Copepoda Milne-Edwards, 1840 - Copepods ** Infra-class Neocopepoda Huys & Boxshall, 1991 *** Super-order Gymnoplea Giesbrecht, 1882 **** Order Calanoida Sars GO, 1903 *** Super-order Podoplea Giesbrecht, 1882 **** Order Cyclopoida Burmeister, 1834 **** Order Gelyelloida Huys, 1988 **** Order Harpacticoida G. O. Sars, 1903 **** Order Misophrioida Gurney, 1933 **** Order Monstrilloida Sars, 1901 **** Order Mormonilloida Boxshall,1979 **** Order Polyarthra Lang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentastomida
The Pentastomida are an enigmatic group of parasitic arthropods commonly known as tongue worms due to the resemblance of the species of the genus ''Linguatula'' to a vertebrate tongue; molecular studies point to them being degenerate crustaceans. About 130 species of pentastomids are known; all are obligate parasites with correspondingly degenerate anatomy. Adult tongue worms vary from about in length, and parasitise the respiratory tracts of vertebrates. They have five anterior appendages. One is the mouth; the others are two pairs of hooks, which they use to attach to the host. This arrangement led to their scientific name, meaning "five openings", but although the appendages are similar in some species, only one is a mouth. Taxonomy Historically significant accounts of tongue worm biology and systematics include early work by Josef Aloys Frölich, Alexander von Humboldt, Karl Asmund Rudolphi, Karl Moriz Diesing and Rudolph Leuckart. Other important summaries have been publ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclida
Cyclida (formerly Cycloidea, and so sometimes known as cycloids) is an extinct order of crab-like fossil arthropods that lived from the Carboniferous to the Cretaceous. Their classification is uncertain, but they are generally interpreted as crustaceans, likely belonging to the superclass Multicrustacea. Description Cycloids have a "striking" resemblance to crabs, and are thought to have inhabited a similar ecological niche, and to have been driven to extinction when crabs became widespread and diverse. The largest members are over across the carapace. Their gills are often preserved in three dimensions, and do not resemble those of other crustaceans. Cycloid taxa differ in the number of walking legs, in the form of the mouthparts and in other significant ways. Affinities There is considerable debate about the placement of cycloids within the Arthropoda. While they are generally considered to be crustaceans of some kind, doubts have been expressed about the homology of cyclo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period mya. Its subdivisions, and its base, are somewhat in flux. The period was established as "Cambrian series" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed. Sedgwick identified the layer as part of his task, along with Roderick Murchison, to subdivide the large "Transition Series", although the two geologists disagreed for a while on the appropriate categorization. The Cambrian is unique in its unusually high proportion of sedimentary deposits, sites of exceptional preservation where "soft" parts of organisms are preserved as well as their more resistant shells. As a result, our understanding of the Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tantulocarida
Tantulocarida is a highly specialised group of parasitic crustaceans that consists of about 33 species, treated as a class in superclass Multicrustacea. They are typically ectoparasites that infest copepods, isopods, tanaids, amphipods and ostracods. Description Eyes are completely absent. Body length Members of this subclass are minute – less than in length and have a dramatic reduction in body form compared to other crustaceans, with an unsegmented, sac-like thorax and a much reduced abdomen. One tantulocarid species, ''Tantulacus dieteri'', is the world's smallest arthropod, with a total body length of only . Life cycle The tantulocarid life cycle is unique among crustaceans. The tantulus larva transforms directly from a non-feeding (lecithotrophic) and free-swimming organism into a parasite without any instars. When entering the parasitic stage much of the body, such as the muscles, degenerates, even if the body itself becomes bigger. As a parasite it is permanentl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eumalacostraca
Eumalacostraca is a subclass of crustaceans, containing almost all living malacostracans, or about 40,000 described species. The remaining subclasses are the Phyllocarida and possibly the Hoplocarida. Eumalacostracans have 19 segments (5 cephalic, 8 thoracic and 6 abdominal). This arrangement is known as the "caridoid facies", a term coined by William Thomas Calman in 1909. The thoracic limbs are jointed and used for swimming or walking. The common ancestor is thought to have had a carapace, and most living species possess one, but it has been lost in some subgroups. Caridoid facies Calman identified the following features as distinguishing eumalacostracan crustaceans: "Carapace enveloping the thoracic region; movably stalked eyes; biramous first antenna; scale-like exopod on the second antenna; natatory exopods on the thoracic limbs; elongate, ventrally flexible abdomen; tail fan formed by the lamellar rami of the uropods on either side of the telson." Classification Martin and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hoplocarida
Hoplocarida is a subclass of crustaceans. The only extant members are the mantis shrimp (Stomatopoda), but two other orders existed in the Palaeozoic: Aeschronectida Aeschronectida is an extinct order of mantis shrimp-like crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapoda, decapods, ostracoda, seed shrimp, branchiopoda, branchiopods, argulida ... and Palaeostomatopoda. References Malacostraca Arthropod subclasses {{Malacostraca-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllocarida
Phyllocarida is a subclass of crustaceans, comprising the extant order Leptostraca and the extinct orders Hymenostraca and Archaeostraca. See also *''Ceratiocaris'' *''Cinerocaris'' *''Vladicaris ''Vladicaris'' is an arthropod known from the Lower Cambrian Paseky Shale member, Czech Republic, where it occurs alongside other arthropods, namely '' Kodymirus vagans'' and ''Kockurus grandis''. It has been attributed to the Crustacea, and if i ...'' References External links Malacostraca Arthropod subclasses Paleozoic crustaceans Mesozoic crustaceans Cenozoic crustaceans Extant Cambrian first appearances Taxa described in 1879 Taxa named by Alpheus Spring Packard {{Malacostraca-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malacostraca
Malacostraca (from New Latin; ) is the largest of the six classes of crustaceans, containing about 40,000 living species, divided among 16 orders. Its members, the malacostracans, display a great diversity of body forms and include crabs, lobsters, crayfish, shrimp, krill, prawns, woodlice, amphipods, mantis shrimp, tongue-eating lice and many other less familiar animals. They are abundant in all marine environments and have colonised freshwater and terrestrial habitats. They are segmented animals, united by a common body plan comprising 20 body segments (rarely 21), and divided into a head, thorax, and abdomen. Etymology The name Malacostraca was coined by a French zoologist Pierre André Latreille in 1802. He was curator of the arthropod collection at the National Museum of Natural History in Paris. The name comes from the Greek roots (', meaning "soft") and (', meaning "shell"). The name is misleading, since the shell is soft only immediately after moulting, and is u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
