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Lethrinus Atkinsoni
''Lethrinus atkinsoni'' is a species of emperor fish described by Alvin Seale in 1910. It is commonly 30 to 35 cm long with a bluish-grey, yellowish, or tan in colour, and a white belly. This species is widespread throughout the west Pacific Ocean. It is a reef-associated fish and is non-migratory. It is solitary or is found in small schools, and lives in seagrass beds and over the sandy bottoms feeding on plankton, mollusks, crustaceans, and other fishes. This fish is caught by humans for food, but less so than other species in the genus due to its small size. Common names Common names include the following, or variants thereof: * Atkinson's emperor * Pacific yellowtail emperor * Reticulated emperorftp://ftp.fao.org/docrep/fao/009/t0242e/T0242E07.pdf * Tamure * Tricky snapper * Tuamotu emperor * Yellow morwong * Yellowtailed emperor Description The upper sides of this species may be bluish-grey, yellowish, or tan in colour. The belly is white. There is sometimes an indisti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alvin Seale
Alvin Seale (July 8, 1871 – July 28, 1958) was a naturalist known for his aquarium design and as an ichthyologist. Early life Alvin Seale was born on July 8, 1871, in Fairmount, Indiana, to a family of Quakers. In 1892, he attended Stanford University, and was tutored by David Starr Jordan. Education In 1896, the year that Seale would have graduated from Stanford in zoology, he was picked by Professor Jordan, along with fellow student Norman B. Scofield, to go to Point Barrow in Alaska. His mission was to look for salmon in the Mackenzie River. Travels Before returning to Stanford Seale collected sea birds along the Alaskan coast on behalf of the British Museum. He also went with his roommate to the Klondike to join the gold rush there. According to Seale, his companion “struck it rich.” Seale, however, was too busy exploring the native wildlife to waste his time searching for gold. In his unpublished diary Seale writes that he spent “an exciting year." Polynesian c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trawling
Trawling is a method of fishing that involves pulling a fishing net through the water behind one or more boats. The net used for trawling is called a trawl. This principle requires netting bags which are towed through water to catch different species of fishes or sometimes targeted species. Trawls are often called towed gear or dragged gear. The boats that are used for trawling are called trawlers or draggers. Trawlers vary in size from small open boats with as little as 30 hp (22 kW) engines to large factory trawlers with over 10,000 hp (7.5 MW). Trawling can be carried out by one trawler or by two trawlers fishing cooperatively (pair trawling). Trawling can be contrasted with trolling. While trawling involves a net and is typically done for commercial usage, trolling instead involves a reed, rod and a bait or a lure and is typically done for recreational purposes. Trawling is also commonly used as a scientific sampling, or survey, method. Bottom vs. midwater trawling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opecoelidae
Opecoelidae is a family of trematodes. It is the largest digenean family with over 90 genera and nearly 900 species, almost solely found in marine and freshwater teleost fishes.Bray, Rodney A., Cribb, Thomas H., Littlewood, D. Timothy J. & Waeschenbach, Andrea (2016). The molecular phylogeny of the digenean family Opecoelidae Ozaki, 1925 and the value of morphological characters, with the erection of a new subfamily. ''Folia Parasitologica'', 63, 1–13. It was considered by Bray ''et al.'' to belong in the superfamily Opecoeloidea Ozaki, 1925 or the Brachycladioidea Odhner, 1905. Genera Family Opecoelidae *Subfamily Bathycreadiinae Martin, Huston, Cutmore & Cribb, 2018Martin, S. B., Huston, D. C., Cutmore, S. C. & Cribb, T. H. (2018). A new classification for deep-sea opecoelid trematodes based on the phylogenetic position of some unusual taxa from shallow-water, herbivorous fishes off south-west Australia. ''Zoological Journal of the Linnean Society'', 186(2), 385–413. **Genus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digenea
Digenea (Gr. ''Dis'' – double, ''Genos'' – race) is a class of trematodes in the Platyhelminthes phylum, consisting of parasitic flatworms (known as ''flukes'') with a syncytial tegument and, usually, two suckers, one ventral and one oral. Adults commonly live within the digestive tract, but occur throughout the organ systems of all classes of vertebrates. Once thought to be related to the Monogenea, it is now recognised that they are closest to the Aspidogastrea and that the Monogenea are more closely allied with the Cestoda. Around 6,000 species have been described to date. Morphology Key features Characteristic features of the Digenea include a syncytial tegument; that is, a tegument where the junctions between cells are broken down and a single continuous cytoplasm surrounds the entire animal. A similar tegument is found in other members of the Neodermata; a group of platyhelminths comprising the Digenea, Aspidogastrea, Monogenea and Cestoda. Digeneans possess a vermifo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isopod
Isopoda is an order of crustaceans that includes woodlice and their relatives. Isopods live in the sea, in fresh water, or on land. All have rigid, segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs on the thorax, and five pairs of branching appendages on the abdomen that are used in respiration. Females brood their young in a pouch under their thorax. Isopods have various feeding methods: some eat dead or decaying plant and animal matter, others are grazers, or filter feeders, a few are predators, and some are internal or external parasites, mostly of fish. Aquatic species mostly live on the seabed or bottom of freshwater bodies of water, but some taxa can swim for a short distance. Terrestrial forms move around by crawling and tend to be found in cool, moist places. Some species are able to roll themselves into a ball as a defense mechanism or to conserve moisture. There are over 10,000 identified species of isopod worldwide, with around 4,5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gnathiidae
The Gnathiidae are a family of isopod crustaceans. They occur in a wide range of depths, from the littoral zone to the deep sea. The adults are associated with sponges and may not feed. The juvenile form is known as a 'praniza', and it is a temporary parasite of marine fish. These forms are not larvae; ''Gnathiidae'' instead become parasitic during the manca stage. Mancae of the ''Gnathiidae'' closely resemble the adult form, however they lack the final pair of pereiopods. Taxonomy in the family relies on male characters, such that females and juveniles cannot be reliably identified. The family contains 182 species, divided among the following genera: *'' Afrignathia'' Hadfield & Smit, 2008 *'' Bathygnathia'' Dollfus, 1901 *'' Bythognathia'' Camp, 1988 *'' Caecognathia'' Dollfus, 1901 *'' Elaphognathia'' Monod, 1926 *'' Euneognathia'' Stebbing, 1893 *'' Gibbagnathia'' Cohen & Poore, 1994 *''Gnathia ''Gnathia'' is a genus of isopod crustaceans, containing the following sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gill
A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia (pl. branchiae) is the zoologists' name for gills (from Ancient Greek ). With the exception of some aquatic insects, the filaments and lamellae (folds) contain blood or coelomic fluid, from which gases are exchanged through the thin walls. The blood carries oxygen to other parts of the body. Carbon dioxide passes from the blood through the thin gill tissue into the water. Gills or gill-like organs, located in different parts of the body, are found in various groups of aquatic animals, including mollusks, crustaceans, insects, fish, and amphibians. Semiterrestrial marine animals such as crabs and mudskippers have gill cham ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monogenea
Monogeneans are a group of ectoparasitic flatworms commonly found on the skin, gills, or fins of fish. They have a direct lifecycle and do not require an intermediate host. Adults are hermaphrodites, meaning they have both male and female reproductive structures.L.A. Tubbsa et al. (2005). "Effects of temperature on fecundity in vitro, egg hatching and reproductive development of ''Benedenia seriolae'' and ''Zeuxapta seriolae'' (Monogenea) parasitic on yellowtail kingfish Seriola lalandi". ''International Journal for Parasitology''(35), 315–327. Some monogeneans are oviparous (egg-laying) and some are viviparous (live-bearing). Oviparous varieties release eggs into the water. Viviparous varieties release larvae, which immediately attach to another host. The genus ''Gyrodactylus'' is an example of a viviparous variety, while the genus ''Dactylogyrus'' is an example of an oviparous variety. Signs and symptoms Freshwater fish that become infected with this parasite become let ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplectanidae
The Diplectanidae are a family of monopisthocotylean monogeneans. They are all parasitic on the gills of fish (marine or freshwater). Diplectanids are small animals, generally around 1 mm in length. As parasites, they can be extremely numerous, up to several thousand on an individual fish. History The family Diplectanidae was proposed by the Italian parasitologist Monticelli in 1903 (as subfamily Diplectaninae). The status of the family and its components was later examined by various authors, including Johnston & Tiegs (1922), Price (1937),Price, E. W. 1937: North American Monogenetic Trematodes. I. The superfamily Gyrodactyloidea ''Journal of the Washington Academy of Sciences'' 27, 146-164PDF Bychowsky (1957), Yamaguti (1963), and Oliver (1987). Morphology Diplectanids are diagnosed by the combination of these three characters: * Presence of accessory adhesive organs on dorsal and ventral part of the haptor, called squamodiscs when they are made up of rodlets and lame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasite
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 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 parasitism, parasitoidism, and micropreda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Host (biology)
In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasite, parasitic, a mutualism (biology), mutualistic, or a commensalism, commensalist ''guest'' (symbiont). The guest is typically provided with nourishment and shelter. Examples include animals playing host to parasitic worms (e.g. nematodes), cell (biology), cells harbouring pathogenic (disease-causing) viruses, a Fabaceae, bean plant hosting mutualistic (helpful) Rhizobia, nitrogen-fixing bacteria. More specifically in botany, a host plant supplies nutrient, food resources to micropredators, which have an evolutionarily stable strategy, evolutionarily stable relationship with their hosts similar to ectoparasitism. The host range is the collection of hosts that an organism can use as a partner. Symbiosis Symbiosis spans a wide variety of possible relationships between organisms, differing in their permanence and their effects on the two parties. If one of the partners in an ass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gillnet
Gillnetting is a fishing method that uses gillnets: vertical panels of netting that hang from a line with regularly spaced floaters that hold the line on the surface of the water. The floats are sometimes called "corks" and the line with corks is generally referred to as a "cork line." The line along the bottom of the panels is generally weighted. Traditionally this line has been weighted with lead and may be referred to as "lead line." A gillnet is normally set in a straight line. Gillnets can be characterized by mesh size, as well as colour and type of filament from which they are made. Fish may be caught by gillnets in three ways: # Wedged – held by the mesh around the body. # Gilled – held by mesh slipping behind the opercula. # Tangled – held by teeth, spines, maxillaries, or other protrusions without the body penetrating the mesh. Most often fish are gilled. A fish swims into a net and passes only part way through the mesh. When it struggles to free ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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