Blackhead Salmon
The blackhead salmon (''Narcetes stomias'') is a species of fish in the family Alepocephalidae (slickheads). Classification Despite the common name, it is not a true salmon, which are in the genus '' Salmo'' and are in the distant Salmoniformes order. Its specific name is from Greek στομίας (''stomias'', "hard-mouthed"). Description The blackhead salmon is blackish in colour. Its maximum length is . Habitat The blackhead salmon lives in the Atlantic Ocean, Indian Ocean and Pacific Ocean; it is bathypelagic The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of below the ocean surface. It lies between the mesopelagic above, and the abyssopelagic below. The bathypelagic ... or benthopelagic, living at depths of . Reproduction The blackhead salmon lays eggs of up to in diameter. The trematode worm '' Olssonium turneri'' (family Fellodistomidae) is a parasite upon it. Referenc ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Charles Henry Gilbert
Charles Henry Gilbert (December 5, 1859 in Rockford, Illinois – April 20, 1928 in Palo Alto, California) was a pioneer ichthyologist and Fisheries science, fishery biologist of particular significance to natural history of the western United States. He collected and studied fishes from Central America north to Alaska and described many new species. Later he became an expert on Pacific salmon and was a noted conservation movement, conservationist of the Pacific Northwest. He is considered by many as the intellectual founder of American fisheries biology. He was one of the 22 "pioneer professors" (founding faculty) of Stanford University. Early life and education Born in Rockford, Illinois, Gilbert spent his early years in Indianapolis, Indiana, where he came under the influence of his high school teacher, David Starr Jordan (1851‒1931). When Jordan became Professor of Natural History at Butler University in Indianapolis, Gilbert followed and received his B.A. degree in 187 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Alepocephalidae
Slickheads, also known as nakedheads or smoothheads, are deep water fishes that belong to the family Alepocephalidae. They are most commonly found in the bathypelagic layer, which is approximately 3000m below the surface. They get their name from the lack of scales on their heads. Similarly, the scientific name is from the Greek ᾰ̓- (''a''-, "not"); λέπος (''lepos'', "scale"); and κεφαλή (''kephalē'', "head"). It has about 22 genera with ca. 96 species. In Japanese they are known as . Description The following characteristics are generally shared by the Alepocephalidae family: Their mouths consist of 80 to 100 razor-sharp teeth, being rather small and feeble. They are shaped in an eel-like elongation, with large eyes, gill rakers that range from moderate to long and numerous, and spineless fins. The single dorsal fin is located posterior to the midpoint of the body and there is no adipose dorsal fin present, there is a pectoral fin ranging from small to rudimenta ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Salmo
''Salmo'' is a genus of ray-finned fish from the family Salmonidae. The single ''Salmo'' species naturally found in the Atlantic North America is the Atlantic salmon, whereas the salmon and trout of the Pacific basin belong to another genus, ''Oncorhynchus''. The natural distribution of ''Salmo'' also extends to North Africa and to West Asia around the Black Sea basin. The generic name ''Salmo'' derives from the Latin ''salmō'' (salmon). The number of distinct species and subspecies in ''Salmo'' is a debated issue. Atlantic salmon and brown trout are widespread species, while most of the other taxa are narrowly distributed forms endemic to single watersheds. Species The species currently listed in this genus are: * ''Salmo abanticus'' Tortonese, 1954 (Lake Abant trout) * ''Salmo aestivalis'' Fortunatov, 1926 (Lake Sevan summer trout) * ''Salmo akairos'' Delling & Doadrio, 2005 (Lake Ifni trout) * ''Salmo aphelios'' Kottelat, 1997 (summer trout) * ''Salmo balcanicus'' ( S. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Salmoniformes
Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes . It includes salmon (both Atlantic and Pacific species), trout (both ocean-going and landlocked), chars, freshwater whitefishes, graylings, taimens and lenoks, which are collectively known as the salmonids ("salmon-like fish"). The Atlantic salmon (''Salmo salar''), whose Latin name became that of its genus '' Salmo'', is also the source of the family and order names. Salmonids have a relatively primitive appearance among the teleost fish, with the pelvic fins being placed far back, and an adipose fin towards the rear of the back. They have slender bodies, with rounded scales and forked tails, and their mouths contain a single row of sharp teeth. Although the smallest species is just long as an adult, most are much larger, with the largest reaching . All salmonids spawn in fresh water of upper reaches of rivers and creeks, but in many cases, the fish spe ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe and Asia from the "New World" of the Americas in the European perception of the World. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and North and South America to the west. As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). The Atlantic Ocean is divided in two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean split at about 8°N. Scientific explorations of the A ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by the Southern Ocean or Antarctica, depending on the definition in use. Along its core, the Indian Ocean has some large marginal or regional seas such as the Arabian Sea, Laccadive Sea, Bay of Bengal, and Andaman Sea. Etymology The Indian Ocean has been known by its present name since at least 1515 when the Latin form ''Oceanus Orientalis Indicus'' ("Indian Eastern Ocean") is attested, named after Indian subcontinent, India, which projects into it. It was earlier known as the ''Eastern Ocean'', a term that was still in use during the mid-18th century (see map), as opposed to the ''Western Ocean'' (Atlantic Ocean, Atlantic) before the Pacific Ocean, Pacific was surmised. Conversely, Ming treasure voyages, Chinese explorers in the Indian Oce ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continents of Asia and Oceania in the west and the Americas in the east. At in area (as defined with a southern Antarctic border), this largest division of the World Ocean—and, in turn, the hydrosphere—covers about 46% of Earth's water surface and about 32% of its total surface area, larger than Earth's entire land area combined .Pacific Ocean . '' Britannica Concise.'' 2008: Encyclopædia Britannica, Inc. The centers of both the [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Bathypelagic
The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of below the ocean surface. It lies between the mesopelagic above, and the abyssopelagic below. The bathypelagic is known as the midnight zone because of the lack of sunlight; this feature does not allow for photosynthesis-driven primary production, preventing growth of phytoplankton or aquatic plants. Although larger by volume than the photic zone, our knowledge of the bathypelagic zone remains limited by our ability to explore the deep ocean. Physical characteristics The bathypelagic zone is characterized by a nearly constant temperature of approximately and a salinity range of 33-35 g/kg. This region has little to no light, because sunlight does not reach this deep in the ocean and bioluminescence is limited. The hydrostatic pressure in this zone ranges 100-400 atmospheres (atm), due to the increase of 1 atm for every 10 m depth. It is belie ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Benthopelagic
The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of the larger profundal zone. Being just above the ocean floor, the demersal zone is variable in depth and can be part of the photic zone where light can penetrate, and photosynthetic organisms grow, or the aphotic zone, which begins between depths of roughly and extends to the ocean depths, where no light penetrates. Fish The distinction between demersal species of fish and pelagic species is not always clear cut. The Atlantic cod (''Gadus morhua'') is a typical demersal fish, but can also be found in the open water column, and the Atlantic herring (''Clupea harengus'') is predominantly a pelagic species but forms large aggregations near the seabed when it spawns on banks of gravel. Two types of fish inhabit the demersal zone: those ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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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]   |