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Acipenser Persicus
The Persian sturgeon (''Acipenser persicus'') is a species of fish in the family Acipenseridae. It is found in the Caspian Sea and to a lesser extent the Black Sea and ascends certain rivers to spawn, mainly the Volga, Kura, Araks and Ural Rivers. It is heavily fished for its flesh and its roe and is limited in its up-river migrations by damming of the rivers. Young fish feed on small invertebrates, graduating to larger prey such as crabs and fish as they grow. The threats faced by this fish include excessive fishing with the removal of immature fish before they have bred, damming of the rivers, loss of spawning areas and water pollution. The International Union for Conservation of Nature has listed the fish as critically endangered and has suggested that the increased provision of hatcheries could be of benefit. Physical appearance The Persian or Caspian sturgeon has an elongated, bulky body with a bluish tint.Kuliev, ZM & Ivanova, LA. "Acipenser persicus". Caspian Environment ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nikolai Andreyevich Borodin
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Gammaridae
Gammaridae is a family of amphipods. In North America they are included among the folk taxonomic category of " scuds", and otherwise gammarids is usually used as a common name. They have a wide distribution, centered on Eurasia, and are euryhaline as a lineage, inhabiting fresh to marine waters. Systematics The Gammaridae were for a long time used as a " wastebin taxon", which included numerous genera of gammaridean amphipods that since then have been removed to their own families, such as the Anisogammaridae, Melitidae, Niphargidae. The following genera are currently listed in the family: *'' Akerogammarus'' Derzhavin & Pjatakova, 1967 *'' Albanogammarus'' Ruffo, 1995 *'' Amathillina'' G. O. Sars, 1894 *'' Axelboeckia'' Stebbing, 1899 *'' Baku'' Karaman & Barnard, 1979 *'' Cephalogammarus'' Karaman & Barnard, 1979 *'' Chaetogammarus'' Martynov, 1924 *'' Comatogammarus'' Stock, 1981 *'' Condiciogammarus'' G. Karaman, 1984 *'' Dershavinella'' Birstein, 1938 *''Dikerogammaru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critically Endangered Fish
As of July 2017, the International Union for Conservation of Nature (IUCN) lists 1,000 critically endangered fish species, including 87 which are tagged as ''possibly extinct''. 3.0% of all evaluated fish species are listed as critically endangered. The IUCN also lists four fish subspecies as critically endangered. Of the subpopulations of fish evaluated by the IUCN, 20 species subpopulations and one subspecies subpopulation have been assessed as critically endangered. Additionally 3191 fish species (21% of those evaluated) are listed as '' data deficient'', meaning there is insufficient information for a full assessment of conservation status. As these species typically have small distributions and/or populations, they are intrinsically likely to be threatened, according to the IUCN. While the category of ''data deficient'' indicates that no assessment of extinction risk has been made for the taxa, the IUCN notes that it may be appropriate to give them "the same degree of at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Of Russia
Fish are aquatic, craniate, gill-bearing animals that lack Limb (anatomy), limbs with Digit (anatomy), digits. Included in this definition are the living hagfish, lampreys, and Chondrichthyes, cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a vertebrate, true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed placodermi, external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Of Iran
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Of Western Asia
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Of Central Asia
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Fish Of Europe
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include non- salty mineral-rich waters such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/ sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes. Fresh water is the water resource that is of the most and immediate use to humans. Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of higher plants and most insects, amphibians, reptiles, mammals and birds need fresh water to survive. Fresh water i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Fish Of Asia
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include non- salty mineral-rich waters such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/ sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes. Fresh water is the water resource that is of the most and immediate use to humans. Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of higher plants and most insects, amphibians, reptiles, mammals and birds need fresh water to survive. Fresh water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Of The Caspian Sea
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Most f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Of The Black Sea
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthropods. Most fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
