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Stichocotyle
''Stichocotyle'' is a monospecific genus of trematodes, in the monospecific family Stichocotylidae, which is itself in the monotypic order Stichocotylida. It comprises the single species ''Stichocotyle nephropis'', which is an internal parasite of elasmobranch fishes. It was originally described from the Norway lobster, ''Nephrops norvegicus'', by J. T. Cunningham in 1884. This flatworm is distinguished by a single ventral row of well separated suckers. ''Stichocotyle'' has not been seen since 1986, and it is possible that it is extinct. Like many parasites, it relied on multiple hosts, and its disappearance is hypothesized to be associated with declines in some of these hosts. The thornback ray ''Raja clavata'' and the barndoor skate ''Dipturus laevis'' were hosts for the adult form, and have declined because they are killed as bycatch Bycatch (or by-catch), in the fishing industry, is a fish or other marine species that is caught unintentionally while fishing for specific sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephrops Norvegicus
''Nephrops norvegicus'', known variously as the Norway lobster, Dublin Bay prawn, ' (compare langostino) or ''scampi'', is a slim, orange-pink lobster which grows up to long, and is "the most important commercial crustacean in Europe". It is now the only extant species in the genus '' Nephrops'', after several other species were moved to the closely related genus '' Metanephrops''. It lives in the north-eastern Atlantic Ocean, and parts of the Mediterranean Sea, but is absent from the Baltic Sea and Black Sea. Adults emerge from their burrows at night to feed on worms and fish. Description ''Nephrops norvegicus'' has the typical body shape of a lobster, albeit narrower than the large genus ''Homarus''. It is pale orange in colour, and grows to a typical length of , or exceptionally long, including the tail and claws. A carapace covers the animal's cephalothorax, while the abdomen is long and segmented, ending in a broad tail fan. The first three pairs of legs bear claws, of wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aspidogastrea
The Aspidogastrea (Ancient Greek: ' “shield”, ' “stomach/pouch”) is a small group of Trematoda, flukes comprising about 80 species. It is a Subclass (biology), subclass of the Trematode, trematoda, and sister group to the Digenea. Species range in length from approximately one millimeter to several centimeters. They are parasites of freshwater and ocean, marine molluscs and vertebrates (Chondrichthyes, cartilaginous and Actinopterygii, bony fishes and turtles). Maturation may occur in the mollusc or vertebrate host. None of the species has any economic importance, but the group is of very great interest to biologists because it has several characters which appear to be archaic. Morphology Shared characteristics Shared characteristics of the group are a large ventral disc with a large number of small Pulmonary alveolus, alveoli ("suckerlets") or a row of suckers and a Tegument (Helminth), tegument with short protrusions, so-called "microtubercles". Larval physiology Larv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joseph Thomas Cunningham
Joseph Thomas Cunningham (1859–1935) was a British marine biologist and zoologist known for his experiments on flatfish and his writings on neo-Lamarckism. Career Cunningham worked at the London Hospital Medical College. He completed his science scholarship at Balliol College, Oxford. Cunningham was a neo-Lamarckian. In his book ''Hormones and Heredity'' (1921) he proposed that the mechanism for the inheritance of acquired characteristics were hormones. He termed this "chemical Lamarckism". According to science historian Peter J. Bowler the idea held by Cunningham that hormones transferred from one generation to the next independent of the germ plasm was seen at the time by neo-Lamarckians as a plausible hypothesis, however "its advocates were unable to get beyond the stage of providing indirect evidence for the effect they postulated." Experiments In a series of experiments (in 1891, 1893 and 1895) on the action of light on the coloration of flatfish, Cunningham directed light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trematode
Trematoda is a class of flatworms known as flukes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive host, where the flukes sexually reproduce, is a vertebrate. Infection by trematodes can cause disease in all five traditional vertebrate classes: mammals, birds, amphibians, reptiles, and fish. Etymology Trematodes are commonly referred to as flukes. This term can be traced back to the Old English name for flounder, and refers to the flattened, rhomboidal shape of the organisms. Taxonomy There are 18,000 to 24,000 known species of trematodes, divided into two subclasses — the Aspidogastrea and the Digenea. Aspidogastrea is the smaller subclass, comprising 61 species. These flukes mainly infect bivalves and bony fishes.https://www.biotaxa.org/Zootaxa/article/view/zootaxa.3918.3.2 Digenea — which comprise the majority of trematodes — ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitism
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as Armillaria mellea, honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the Orobanchaceae, broomrapes. There are six major parasitic Behavioral ecology#Evolutionarily stable strategy, strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), wikt:trophic, trophicallytransmitted parasitism (by being eaten), Disease vector, vector-transmitted paras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elasmobranchii
Elasmobranchii () is a subclass of Chondrichthyes or cartilaginous fish, including sharks (superorder Selachii), rays, skates, and sawfish (superorder Batoidea). Members of this subclass are characterised by having five to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins and small placoid scales on the skin. The teeth are in several series; the upper jaw is not fused to the cranium, and the lower jaw is articulated with the upper. The details of this jaw anatomy vary between species, and help distinguish the different elasmobranch clades. The pelvic fins in males are modified to create claspers for the transfer of sperm. There is no swim bladder; instead, these fish maintain buoyancy with large livers rich in oil. The definition of the clade is unclear with respect to fossil chondrichthyans. It has been used by different authors as equivalent to Neoselachii (the clade including modern sharks and rays and their last common ancestor) or for al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Invertebrate Pathology
The ''Journal of Invertebrate Pathology'' is a peer-reviewed scientific journal publishing research on the induction and pathogenesis of diseases of invertebrates, owned by Academic Press (part of Elsevier). The journal publishes the results of physiological, morphological, genetic, immunological, and ecological studies as related to the etiologic agents of diseases of invertebrates, including the suppression of diseases in beneficial species, and the use of diseases in controlling undesirable species. It was founded by American microbiologist Edward Arthur Steinhaus in 1959 as the ''Journal of Insect Pathology'', renamed in 1965, and in 1968 adopted as the official journal of the Society for Invertebrate Pathology shortly after it was also founded by Steinhaus. See also * Arbovirus * List of Elsevier periodicals * List of entomology journals The following is a list of entomological Entomology () is the scientific study of insects, a branch of zoology. In the past th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thornback Ray
The thornback ray (''Raja clavata''), or thornback skate, is a species of ray fish in the family Rajidae. Distribution The Thornback ray is found in the Atlantic coastal waters of Europe and western Africa. It is also present from south Africa to the southwestern Indian Ocean and in the Mediterranean and Black Seas. It is native possibly as far south as Namibia and South Africa. Its natural habitats are open large seas and shallow seas. It is sometimes seen trapped in large estuarine pools at low tide. The thornback ray is probably one of the most common rays encountered by divers. Habitat The thornback ray is usually found on sedimentary seabeds such as mud, sand or gravel at depths between 10-60m. Juvenile fish feed on small crustaceans, particularly amphipods and bottom-living shrimps; adults feed on crabs, shrimps and small fish. Description Like all rays, the thornback ray has a flattened body with broad, wing-like pectoral fins. The body is kite-shaped wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barndoor Skate
The barndoor skate (''Dipturus laevis'') is a species of marine cartilaginous fish in the skate family Rajidae of the order Rajiformes. It is native to the northwestern Atlantic Ocean, and is found from the Grand Banks of Newfoundland and the southern side of the Gulf of St. Lawrence south to North Carolina. The fish is one of the largest skates found in the North Atlantic Ocean, reaching lengths up to . It is carnivorous, feeding on invertebrates and other fish found near the sea floor. After peaking in the 1950s, the population of the barndoor skate dramatically declined in the 1960s and early 1970s as a result of overfishing. In 2003, it was listed as endangered by the World Conservation Union. However, barndoor skate populations have increased substantially since 1990 and even surpassed 1960s population size by 2012. In 2019, the barndoor skate was downlisted to least concern by the IUCN based on its largely increased population, new protections within its range, and al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bycatch
Bycatch (or by-catch), in the fishing industry, is a fish or other marine species that is caught unintentionally while fishing for specific species or sizes of wildlife. Bycatch is either the wrong species, the wrong sex, or is undersized or juveniles of the target species. The term "bycatch" is also sometimes used for untargeted catch in other forms of animal harvesting or collecting. Non- marine species (freshwater fish not saltwater fish) that are caught (either intentionally or unintentionally) but regarded as generally "undesirable" are referred to as "rough fish" (mainly US) and " coarse fish" (mainly UK). In 1997, the Organisation for Economic Co-operation and Development (OECD) defined bycatch as "total fishing mortality, excluding that accounted directly by the retained catch of target species". Bycatch contributes to fishery decline and is a mechanism of overfishing for unintentional catch. The average annual bycatch rate of pinnipeds and cetaceans in the US from 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasites Of Crustaceans
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the broomrapes. There are six major parasitic strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), trophicallytransmitted parasitism (by being eaten), vector-transmitted parasitism, parasitoidism, and micropredation. One major axis of classification concerns invasiveness: an endoparasite lives inside the host's body; an ect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trematode Genera
Trematoda is a class of flatworms known as flukes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive host, where the flukes sexually reproduce, is a vertebrate. Infection by trematodes can cause disease in all five traditional vertebrate classes: mammals, birds, amphibians, reptiles, and fish. Etymology Trematodes are commonly referred to as flukes. This term can be traced back to the Old English name for flounder, and refers to the flattened, rhomboidal shape of the organisms. Taxonomy There are 18,000 to 24,000 known species of trematodes, divided into two subclasses — the Aspidogastrea and the Digenea. Aspidogastrea is the smaller subclass, comprising 61 species. These flukes mainly infect bivalves and bony fishes.https://www.biotaxa.org/Zootaxa/article/view/zootaxa.3918.3.2 Digenea — which comprise the majority of trematodes — are f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
