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 while position of 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 arapaima, pirarucu, or paiche is any large species of bonytongue in the genus Arapaima native to the Amazon and Essequibo basins of South America. Arapaima is the type genus of the subfamily Arapaiminae within the family Osteoglossidae. They are among the world's largest freshwater fish, reaching as much as 3 m (9.8 ft) in length. They are an important food fish. They have declined in the native range due to overfishing and habitat loss. In contrast, arapaima have been introduced to several tropical regions outside the native range, where they are sometimes considered invasive species. In Kerala, India, arapaima escaped from aquaculture ponds after floods in 2018. Its Portuguese name, pirarucu, derives from the Tupi language words pira and urucum, meaning "red fish".
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.
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.
Pterygoplichthys gibbiceps is a species of armored catfish native to Brazil, Ecuador, Peru and Venezuela where it is found in the Orinoco and Amazon basins.
The rummy-nose tetra is a species of tropical freshwater characin fish originating in South America, popular among fishkeepers as a tropical aquarium fish. One of many small tetras belonging to the same genus, it is on average 5 cm (2 in) long when fully grown. The fish is one of several very similar species including Petitella bleheri, and Petitella georgiae, and it is possible that more recently collected specimens available in the aquarium trade are members of one or other of these similar species. The common name applied to most of these fishes is "rummy-nose tetra", though other common names are in circulation.
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.
The redeye tetra, is a species of tetra from the São Francisco, upper Paraná, Paraguay and Uruguay river basins in eastern and central South America. This freshwater fish is commonly kept in aquariums and bred in large numbers at commercial facilities in Eastern Europe and Asia. The redeye tetra is one of the more popular aquarium fish due to their schooling capability.
Leiarius is a genus of long-whiskered catfishes native to South America. Most of the genus' species are found in the aquarium hobby as ornamental fish.
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.
