The Percidae are a family of ray-finned fish, part of the order Perciformes, which are found in fresh and brackish waters of the Northern Hemisphere. The majority are Nearctic, but there are also Palearctic species. The family contains more than 200 species in 11 genera. The perches and their relatives are in this family; well-known species include the walleye, sauger, ruffe, and three species of perch. However, small fish known as darters are also a part of this family.
Sciaenidae is a family of ray-finned fishes belonging to the order Acanthuriformes. They are commonly called drums or croakers in reference to the repetitive throbbing or drumming sounds they make. The family consists of about 293 to 298 species in about 66 or 67 genera.
The Serranidae are a large family of fishes belonging to the order Perciformes. The family contains about 450 species in 65 genera, including the sea basses and the groupers. Although many species are small, in some cases less than 10 cm (3.9 in), the giant grouper is one of the largest bony fishes in the world, growing to 2.7 m in length and 400 kg (880 lb) in weight. Representatives of this group live in tropical and subtropical seas worldwide.
Salmonidae is a family of ray-finned fish that constitutes the only currently extant family in the order Salmoniformes, consisting of 11 extant genera and over 200 species collectively known as "salmonids". The family includes salmon, trout, char, graylings, freshwater whitefishes, taimens and lenoks, all coldwater mid-level predatory fish that inhabit the subarctic and cool temperate waters of the Northern Hemisphere. The Atlantic salmon, whose Latin name became that of its genus Salmo, is also the eponym of the family and order names.
Characidae, the characids or characins is a family of freshwater subtropical and tropical fish, belonging to the order Characiformes. The name "characins" is the historical one, but scientists today tend to prefer "characids" to reflect their status as a by and large monophyletic group at family rank. To arrive there, this family has undergone much systematic and taxonomic change. Among those fishes that remain in the Characidae for the time being are the tetras, comprising the very similar genera Hemigrammus and Hyphessobrycon, as well as a few related forms such as the cave and neon tetras. Fish of this family are important as food and also include popular aquarium fish species.
The Gonorynchiformes are an order of ray-finned fish that includes the important food source, the milkfish, and a number of lesser-known types, both marine and freshwater.
Callichthyidae is a family of catfishes, called armored catfishes due to the two rows of bony plates along the lengths of their bodies. It contains some of the most popular freshwater aquarium fish, such as many species in the genus Corydoras.
A piranha or piraña is one of a number of freshwater fish in the family Serrasalmidae, or the subfamily Serrasalminae within the tetra family, Characidae in order Characiformes. These fish inhabit South American rivers, floodplains, lakes and reservoirs. Although often described as extremely predatory and mainly feeding on fish, their dietary habits vary extensively, and they will also take plant material, leading to their classification as omnivorous.
The Scorpaenidae are a family of mostly marine fish that includes many of the world's most venomous species. As their name suggests, scorpionfish have a type of "sting" in the form of sharp spines coated with venomous mucus. The family is a large one, with hundreds of members. They are widespread in tropical and temperate seas but mostly found in the Indo-Pacific. They should not be confused with the cabezones, of the genus Scorpaenichthys, which belong to a separate, though related, family, Cottidae.
Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes.
Batrachoididae is the only family in the ray-finned fish order Batrachoidiformes. Members of this family are usually called toadfish or frogfish: both the English common name and scientific name refer to their toad-like appearance.
Nannostomus is a genus of fish belonging to the characin family Lebiasinidae. All of the species in this genus are known as pencil fish, a popular name that was initially only applied to two species in the 1920s, Nannostomus unifasciatus and Nannostomus eques, by the late 1950s however, the term would be applied to all members of the genus. Several species have become popular aquarium fish due to their attractive coloration, unique shape, and interesting demeanor.
Trichomycteridae is a family of catfishes commonly known as pencil catfishes or parasitic catfishes. This family includes the candiru fish, feared by some people for its alleged habit of entering into the urethra of humans. They are one of the few parasitic chordates. Another species is the life monsefuano which was important to the Moche culture and still an important part of Peruvian cuisine.
The Cetopsidae are a small family of catfishes, commonly called the whale catfishes.
The Aspredinidae are a small South American family of catfishes also known as the banjo catfishes, with about 43 species.
Cynodontidae, also known as dogtooth characins or vampire tetras, are a family of predatory, characiform freshwater fishes from South America. This group is not very diverse, and includes only five genera and 14 species. Most of what is known about this family is from the members of the subfamily Cynodontinae, which includes the largest species of this family, up to 117 cm (3.84 ft). The members of subfamily Roestinae only reach up to 20 cm (7.9 in). and are less known.
The Astronotinae are a subfamily of cichlids from South America, where they are found in the Amazon, Orinoco, Paraná, and Paraguay River basins, and various rivers in the Guianas. The subfamily includes three genera, each with two species. Although in other classifications all three genera are placed in the subfamily Cichlinae with Astronotus being the only genus in the monogeneric tribe Astronotini of the subfamily Cichlinae and the other two genera being placed in the tribe Cichlini.
The Catostomidae are the suckers of the order Cypriniformes, with about 78 species in this family of freshwater fishes. The Catostomidae are almost exclusively native to North America. The only exceptions are Catostomus catostomus, found in both North America and Russia, and Myxocyprinus asiaticus found only in China. In the Ozarks they are a common food fish and a festival is held each year to celebrate them. The bigmouth buffalo, Ictiobus cyprinellus, can reach an age up to 127 years, making it the oldest known freshwater teleost by more than 50 years.
Lebiasina is a genus of fishes found in tropical South America, where they inhabit well-oxygenated upland streams that originate in the Andes of Colombia, Ecuador and Peru, the Guianan Highlands in Brazil, Guyana and Venezuela, and Serra do Cachimbo in Brazil. The individual species tend to have relatively small ranges and the three species of Serra do Cachimbo, all restricted to the Curuá River basin, are considered threatened by Brazil's Ministry of the Environment.
Nannostomus beckfordi,, commonly known as the golden pencil fish or Beckford's pencil fish, is a freshwater species of fish belonging to the characin family Lebiasinidae. It occurs widely and commonly in swamps and slow-moving waters in Brazil, Guyana, French Guiana, and Suriname.
