Goldfish
The goldfish (Carassius auratus auratus) is a freshwater fish in the family Cyprinidae of order Cypriniformes. It was one of the earliest fish to be domesticated, and is one of the most commonly kept aquarium fish.
A relatively small member of the carp family (which also includes the koi carp and the crucian carp), the goldfish is a domesticated version of a less-colorful carp (Carassius auratus) native to east Asia. It was first domesticated in China more than a thousand years ago, and several distinct breeds have since been developed. Goldfish breeds vary greatly in size, body shape, fin configuration and coloration (various combinations of white, yellow, orange, red, brown, and black are known).
A relatively small member of the carp family (which also includes the koi carp and the crucian carp), the goldfish is a domesticated version of a less-colorful carp (Carassius auratus) native to east Asia. It was first domesticated in China more than a thousand years ago, and several distinct breeds have since been developed. Goldfish breeds vary greatly in size, body shape, fin configuration and coloration (various combinations of white, yellow, orange, red, brown, and black are known).
Catfish
Catfishes (order Siluriformes) are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores (species that eat dead material on the bottom), and even to a tiny parasitic species commonly called the candiru, Vandellia cirrhosa. There are armour-plated types and also naked types, neither having scales. Despite their name, not all catfish have prominent barbels; members of the Siluriformes order are defined by features of the skull and swimbladder. Catfish are of considerable commercial importance; many of the larger species are farmed or fished for food. Many of the smaller species, particularly the genus Corydoras, are important in the aquarium hobby. Catfish are nocturnal.[2][3]
Piranha
Piranhas belong to the subfamily Serrasalminae, which includes closely related omnivorous[3] fish such as pacus.[4] Traditionally, only the four genera Pristobrycon, Pygocentrus, Pygopristis and Serrasalmus are considered to be true piranhas, due to their specialized teeth. However, a recent analysis showed that, if the piranha group is to be monophyletic, it should be restricted to Serrasalmus, Pygocentrus and part of Pristobrycon, or expanded to include these taxa plus Pygopristis, Catoprion, and Pristobrycon striolatus. Pygopristis was found to be more closely related to Catoprion than the other three piranha genera.[4]
The total number of piranha species is unknown and contested, and new species continue to be described. Estimates range from fewer than 30 to more than 60.[4]
The total number of piranha species is unknown and contested, and new species continue to be described. Estimates range from fewer than 30 to more than 60.[4]
Trout
Trout is the name for a number of species of freshwater fish belonging to the genera Oncorhynchus, Salmo and Salvelinus, all of the subfamily Salmoninae of the family Salmonidae. The word trout is also used as part of the name of some non-salmonid fish such as Cynoscion nebulosus, the spotted seatrout or speckled trout.
Trout are closely related to salmon and char (or charr): species termed salmon and char occur in the same genera as do trout (Oncorhynchus - Pacific salmon and trout, Salmo - Atlantic salmon and various trout, Salvelinus - char and trout).
Most trout such as Lake trout live in freshwater lakes and/or rivers exclusively, while there are others such as the Rainbow trout which may either live out their lives in fresh water, or spend two or three years at sea before returning to fresh water to spawn, a habit more typical of salmon. A rainbow trout that spends time in the ocean is called a steelhead.
Trout are an important food source for humans and wildlife including brown bears, birds of prey such as eagles, and other animals. They are classified as oily fish.[1]
Trout are closely related to salmon and char (or charr): species termed salmon and char occur in the same genera as do trout (Oncorhynchus - Pacific salmon and trout, Salmo - Atlantic salmon and various trout, Salvelinus - char and trout).
Most trout such as Lake trout live in freshwater lakes and/or rivers exclusively, while there are others such as the Rainbow trout which may either live out their lives in fresh water, or spend two or three years at sea before returning to fresh water to spawn, a habit more typical of salmon. A rainbow trout that spends time in the ocean is called a steelhead.
Trout are an important food source for humans and wildlife including brown bears, birds of prey such as eagles, and other animals. They are classified as oily fish.[1]
SAlmon
Salmon /ˈsæmən/ is the common name for several species of fish in the family Salmonidae. Several other fish in the same family are called trout; the difference is often said to be that salmon migrate and trout are resident,[citation needed] but this distinction does not strictly hold true. Salmon live along the coasts of both the North Atlantic (the migratory species Salmo salar) and Pacific Oceans (half a dozen species of the genus Oncorhynchus), and have also been introduced into the Great Lakes of North America. Salmon are intensively produced in aquaculture in many parts of the world.
Typically, salmon are anadromous: they are born in fresh water, migrate to the ocean, then return to fresh water to reproduce. However, populations of several species are restricted to fresh water through their lives. Folklore has it that the fish return to the exact spot where they were born to spawn; tracking studies have shown this to be true, and this homing behavior has been shown to depend on olfactory memory.[2][3]
Typically, salmon are anadromous: they are born in fresh water, migrate to the ocean, then return to fresh water to reproduce. However, populations of several species are restricted to fresh water through their lives. Folklore has it that the fish return to the exact spot where they were born to spawn; tracking studies have shown this to be true, and this homing behavior has been shown to depend on olfactory memory.[2][3]