The Amazon river dolphin, also known as the boto, bufeo or pink river dolphin, is a species of toothed whale endemic to South America and is classified in the family Iniidae. Three subspecies are currently recognized: I. g. geoffrensis, I. g. boliviensis and I. g. humboldtiana. The position of the Araguaian river dolphin within the clade is still unclear. The three subspecies are distributed in the Amazon basin, the upper Madeira River in Bolivia, and the Orinoco basin, respectively.
The neon tetra is a freshwater fish of the characin family of order Characiformes. The type species of its genus, it is native to blackwater and clearwater streams in the Amazon basin of South America. Its bright colouring makes the fish visible to conspecifics in the dark blackwater streams, and is also the main reason for its popularity among freshwater fish hobbyists, with neon tetras being one of the most widely kept tropical fish in the world.
The Asian arowana comprises several phenotypic varieties of freshwater fish distributed geographically across Southeast Asia. While most consider the different varieties to belong to a single species, work by Pouyaud et al. (2003) differentiates these varieties into multiple species. They have several other common names, including Asian bonytongue, dragonfish, and a number of names specific to the different color varieties.
The cardinal tetra is a freshwater fish of the family Characidae of order Characiformes. It is native to the upper Orinoco and Negro Rivers in South America. Growing to about 3 cm (1.2 in) total length, the cardinal tetra has the striking iridescent blue line characteristic of the genus Paracheirodon laterally bisecting the fish, with the body below this line being vivid red in color, hence the name "cardinal tetra". The cardinal tetra's appearance is similar to that of the closely related neon tetra, with which it is often confused; the neon's red coloration extends only about halfway to the nose, and the neon's blue stripe is a less vibrant blue.
The mata mata, mata-mata, or matamata is a South American species of freshwater turtle found in the Amazon basin and river system of the eastern Guianas. It was formerly believed to also occur in the Orinoco basin, western Guianas and upper Rio Negro–Branco system, but in 2020 these populations were found to belong to a separate species, Chelus orinocensis. Subsequently, some authorities have modified the common name of Chelus fimbriata to Amazon mata mata. These two are the only extant species in the genus Chelus.
Corydoras is a genus of freshwater catfish in the family Callichthyidae and subfamily Corydoradinae. The species usually have more restricted areas of endemism than other callichthyids, but the area of distribution of the entire genus almost equals the area of distribution of the family, except for Panama where Corydoras is not present. Corydoras species are distributed in South America where they can be found from the east of the Andes to the Atlantic coast, from Trinidad to the Río de la Plata drainage in northern Argentina. Species assigned to Corydoras display a broad diversity of body shapes and coloration. Corydoras are small fish, ranging from 2.5 to 12 cm in SL., and are protected from predators by their body armor and by their sharp, typically venomous spines.
Polypterus senegalus, commonly known as the Senegal bichir, gray bichir or Cuvier's bichir, is an African species of ray-finned fish in the bichir family, Polypteridae. It is a typical example of polypterid fishes, as most of its defining physical features are common across the genus, such as its ancient, lungfish- or arowana-like appearance, the ability to breathe atmospheric oxygen, and its armor-like scales. These factors have influenced the species' popularity in captivity, and it is commonly kept by aquarists and other hobbyists.
Osteoglossum is a genus of fish in the family Osteoglossidae. They reach about 1 m (3.3 ft) in length and are restricted to freshwater habitats in tropical South America.
River stingrays or freshwater stingrays are Neotropical freshwater fishes of the family Potamotrygonidae in the order Myliobatiformes, one of the four orders of batoids, cartilaginous fishes related to sharks. They are found in rivers in tropical and subtropical South America. A single marine genus, Styracura, of the tropical West Atlantic and East Pacific are also part of Potamotrygonidae. They are generally brownish, greyish or black, often with a mottled, speckled or spotted pattern, have disc widths ranging from 31 to 200 centimetres (1.0–6.6 ft) and venomous tail stingers. River stingrays feed on a wide range of smaller animals and the females give birth to live young. There are more than 35 species in five genera.
The genus Panaque contains a small number of small to medium-sized South American suckermouth armoured catfishes that are notable for being among the very few vertebrates that feed extensively on wood. In addition, algae and aufwuchs are an important part of the diet, and they use their rasping teeth to scrape this from rocks. These fish are also popular aquarium fish, where the sound of scraping as these fish forage for food is easily audible.
The black arowana is a South American freshwater bony fish of the family Osteoglossidae. Black arowanas are sometimes kept in aquariums, but they are predatory and require a very large tank. It is generally common, but large numbers are caught as food and for the aquarium fish trade.
The southern saratoga, also known as the spotted bonytongue, spotted saratoga, or simply saratoga, is a freshwater bony fish native to Australia. It belongs to the subfamily Osteoglossinae, or arowanas, a primitive group of teleosts. Like all arowanas, it is a carnivorous mouthbrooder. Along with the gulf saratoga, the saratoga is also known as the Australian arowana and barramundi, although the latter name is nowadays reserved in Australia for the unrelated Lates calcarifer.
The redtail catfish, Phractocephalus hemioliopterus, is a large species of South American pimelodid (long-whiskered) catfish. It is known in Venezuelan Spanish as cajaro; in Guyana, it is known as a banana catfish, and in Brazil it is known as pirarara, a fusion of words from the indigenous Tupi language: pirá and arara. It is the only extant species of its genus, Phractocephalus.
The red-bellied piranha, also known as the red piranha, is a type of piranha native to South America, found in the Amazon, Paraguay, Paraná and Essequibo basins, as well as coastal rivers of northeastern Brazil. This fish is locally abundant in its freshwater habitat. They are omnivorous foragers and feed on insects, worms, crustaceans, and fish. They are not a migratory species but do travel to seek out conditions conducive to breeding and spawning during periods of increased rainfall. Red-bellied piranhas often travel in shoals as a predatory defense but rarely exhibit group hunting behavior. Acoustic communication is common and is sometimes exhibited along with aggressive behaviors. They are a popular aquarium fish.
Oxydoras niger, the ripsaw catfish or cuiu cuiu, is a species of thorny catfish native to the Amazon, Essequibo and São Francisco basins in Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru and Venezuela. This species grows to a length of 100 centimetres (39 in) SL and weights up to 13 kilograms (29 lb). This species is a minor component of local commercial fisheries. It has lateral thorns that can damage any potential predator or handler. It feeds by shifting through sand and detecting eatable parts with the taste receptors in the roof and floor of its mouth.
Apistogramma agassizii, commonly known as Agassiz's dwarf cichlid, is a species of cichlid found in the Marañón and Ucayali River in Peru, some tributaries of the Amazon River, as well as downstream to the estuary in the Atlantic. It is named after the Swiss-American zoologist and geologist Louis Agassiz (1807–1873).
Hyphessobrycon heterorhabdus, commonly known as the flag tetra or Belgian flag tetra, is a species of freshwater characin fish endemic to Brazil. Belonging to the family Characidae, this species is distinguished by its vibrant coloration and patterns, which have contributed to its popularity in the aquarium trade.
Arapaiminae is a subfamily of freshwater osteoglossiform (bony-tongued) fishes belonging to the family Osteoglossidae. It includes the South American arapaimas of the Amazon and Essequibo basins and the African arowana from the watersheds of the Sahelo-Sudanese region, Senegal, Gambia, and parts of Eastern Africa. This subfamily is sometimes raised to the rank of family, as Arapaimidae. A commonly used synonym is Heterotidinae, but according to the ICZN, Arapaiminae has priority.
Brachyplatystoma rousseauxii, the gilded catfish or dourada, is a species of catfish of the family Pimelodidae that is native to Amazon and Orinoco River basins and major rivers of French Guiana.
Iguanodectes rachovii is a species of freshwater fish that inhabits the rivers of the Amazon basin. It largely consumes insects, though it will eat plants if given the opportunity, and has a peaceful disposition, able to live alongside various other species. It is often found in groups of 3 to 30 specimens, lingering at the edges of streams near the surface of the water.
