Ancistrus is a genus of nocturnal freshwater fish in the family Loricariidae of order Siluriformes, native to freshwater habitats in South America and Panama. Fish of this genus are common in the aquarium trade where they are known as bushynose or bristlenose catfish. In the aquarium hobby they are often referred to as bushynose or bristlenose plecos instead, but this may lead to confusion as "pleco" usually is used for Hypostomus plecostomus and its allies and is often used as a catchall term for any loricariids remotely resembling that species.
Acestrorhynchus is a genus of 14 species of characiform fish found only in fresh water in South America, the sole genus in the family Acestrorhynchidae. Their greatest diversity is in the Orinoco and Amazon basins.
Hyphessobrycon is a genus of freshwater fish in the family Characidae. These species are among the fishes known as tetras. The genus is distributed in the Neotropical realm from southern Mexico to Río de la Plata in Argentina. Many of these species are native to South America; about six species are from Central America and a single species, H. compressus is from southern Mexico.
Astyanax is a genus of freshwater fish in the family Characidae of the order Characiformes. Some of these fish, like many of their relatives, are kept as aquarium pets and known collectively as tetras. With around 150 described species and new ones being described yearly, this genus is among the largest of the entire order; Hyphessobrycon also has more than 145 species and which one is larger at any one time depends on whether more species have been recently described in one or the other. The blind and colorless cave tetra of Mexico is a famous member of the genus, but its taxonomic position is disputed: Some recognize it as part of the Mexican tetra and this is supported by phylogenetic evidence, but others recognize the cave form as a separate species, A. jordani.
Crenicichla is a genus of cichlids native to South America commonly known as the pike cichlids. They are found in most tropical and subtropical freshwater habitats between the Andes and the Atlantic.
Leporinus is a genus of fish in the family Anostomidae native to South America. The fossil species Leporinus scalabrinii, known from the late Miocene of Entre Ríos in Argentina, has only recently been added to this genus after being misidentified as a species of primate under the name Arrhinolemur scalabrinii for over 100 years.
Notropis is a genus of freshwater fish in the family Cyprinidae. They are known commonly as eastern shiners. They are native to North America, and are the continent's second largest genus.
Pimelodus is a genus of fish in the family Pimelodidae native to Central and South America.
Pimelodella is a genus of three-barbeled catfishes.
Auchenipterus is a genus of driftwood catfishes.
Bryconamericus is a genus of characins found in Central and South America.
Cynopotamus is a genus of characin fishes from South America, with 12 currently described species:
Deuterodon is a genus of characins from river basins in southern and southeastern Brazil, with a single species of uncertain taxonomic status, D. potaroensis, from Guyana. These are small fish that reach up to 12.6 cm (5.0 in) in total length. They are omnivores with a specialized mouth structure that allows them to scrape algae and debris off bedrock.
Knodus is a genus of characins, small freshwater fish from South America.
Phenacogaster is a genus of characins from South America, with 20 currently described species:
Caenotropus is a genus of chilodontid headstanders from South America, found in the Orinoco, Parnaíba, and Amazon Basins, as well as various rivers in the Guianas. The currently described species in this genus are:
Rhamdella is a genus of three-barbeled catfishes native to South America.
The glass headstander,, is a species of fish in the genus Charax. commonly known as the transparent tetra.
Charax stenopterus is a small species of South American fish in the genus Charax.
