A fish is any gill-bearing aquatic vertebrate (or craniate) animal that lacks limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups. Because the term is defined negatively, and excludes the tetrapods (i.e., the amphibians, reptiles, birds and mammals) which descend from within the same ancestry, it is paraphyletic. The traditional term pisces (also ichthyes) is considered a typological, but not a phylogenetic classification.
Most fish are "cold-blooded", or ectothermic, allowing their body temperatures to vary as ambient temperatures change. Fish are abundant in most bodies of water. They can be found in nearly all aquatic environments, from high mountain streams (char and gudgeon) to the abyssal and even hadal depths of the deepest oceans (gulpers and anglerfish). At 31,900 species, fish exhibit greater species diversity than any other class of vertebrates.
Fish, especially as food, are an important resource worldwide. Commercial and subsistence fishers hunt fish in wild fisheries (see fishing) or farm them in ponds or in cages in the ocean (see aquaculture). They are also caught by recreational fishers, kept as pets, raised by fishkeepers, and exhibited in public aquaria. And Here Are the 9 Most Wanted River Monsters look strange and most wanted:
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African Lungfish
This river creatures is quite strange in my opinion. For people who've never seen it, Definitely, will think of this creature as a monster because look so creepy.
However, despite its terrible, this animal is totally harmless. These fish adapt to its environment is less oxygen, making this fish rarely seen by humans. |
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Goliath Tigerfish
With up to 1.5 meters long and sharp teeth, of course many people are afraid to look this spooky fish.
Goliath Tigerfish is the largest variant in the family Tigerfish, and is a great predator. This fish is famous for its strength and speed. |
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| A vampire piranha? Actually a payara, a member of the piranha family with huge teeth. |
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Mekong Giant Catfish
Surely most readers already know this one fish. These Fish are almost similar to the whale shark, is the largest freshwater fish ever found and is from China. The biggest size is closer to whales than freshwater fish in general. |
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Bagarius Yarelli
Known also as the "Yeti of the river" or meat-eating Catfish. This fish has teeth - sharp teeth with a long reach 1 inch. In fact, the fish habitat in several countries in Asia are said to like to eat human flesh, although still a rumor. |
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Alligator Gar
This one River creatures looks like a mix between alligators and fish. Animals that live in North America is rarely hunt prey, but wait for prey that passes in front of his mouth, then he pounced with remarkable speed. |
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| The Arapaima, Pirarucu, or Paiche (Arapaima gigas) is a South American tropical freshwater fish. It is a living fossil and one of the largest freshwater fishes in the world. |
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Chinese Paddlefish, Psephurus gladius , also known as Chinese Swordfish, are among the largest freshwater fish. It is one of two extant paddlefish species, the other being the American Paddlefish. It is also called "elephant fish" because its snout resembles an elephant trunk. More poetically, it is sometimes referred to as the "Giant Panda of the Rivers", not because of any physical resemblance to a panda, but because of its rarity and protected status.
The Chinese Paddlefish is the People's Republic of China's first-level protected animal. Its belly is white and back and head grey. They live mostly in the middle or lower part of the Yangtze (Chang Jiang), occasionally in large lakes. They feed on other fish, with a small amount of crabs and crayfish. They are sexually mature at seven or eight, with a body length of 2 metres and a weight of 25 kilograms.
It is said that the zoologist Bǐng Zhì (秉志) recorded around the 1950s that some fishermen caught a paddlefish of 7-metres, although the authenticity of the story is unconfirmed. It is said that the Chinese paddlefish can grow to 23 feet and weigh 1,100 pounds, but little research on a maximum size can be conducted today due to the species' scarcity.
Due to overfishing, the Chinese Paddlefish is critically endangered now, and officially recognized by the People's Republic in 1983 to prevent fishing of paddlefish young or adults. Paddlefish are also threatened by dams (like the Three Gorges Dam), which divide the population into isolated groups. The fish are rarely seen, recently raising concerns that the species might already be extinct. During a three-year search conducted from 2006-2008 a research team from the Chinese Academy of Fisheries Science in Jingzhou failed to find one specimen. The last confirmed sighting of the fish alive occurred January 24, 2003 on the Yangtze.However, a 3.6-meter, 250 kilogram specimen was killed by illegal fishing on January 8, 2007, in Jiayu County on the Yangtze River. |
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The Piraiba Catfish is the largest catfish in the Amazon River. That Fish can reach 3 meters in length with a weight of 272 kg was scared most of the anglers. This fish is famous for its strength, even the fish are said to be able to make a man drowned in his might.
A lot of rumors that circulated when the cause of the missing anglers when fishing in the river is being dragged by the fish into the river to drown ?. |
