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.
Otocinclus is a genus of catfish in the family Loricariidae native to South America, commonly known as "dwarf suckers" or "otos". This genus, like other loricariids, is characterized by rows of armour plating covering the body, as well as the underslung suckermouth. They are generally small in size; O. tapirape is the smallest of the species (2.4 cm), while O. flexilis is the biggest (5.5 cm). These species have adaptations that allow them to breathe air. A duct forms at the junction between the esophagus and the stomach and expands into an enlarged, ring-like diverticulum, characteristic of this genus, which allows air-breathing. Otocinclus are popular aquarium fish, and they are often purchased as algae eaters. It is difficult to breed them in captivity, and only wild caught Otocinclus are available to hobbyists. This genus is widely distributed east of the Andes of South America, throughout the lowlands from northern Venezuela to northern Argentina, but are generally absent from the Amazon and the Orinoco lowlands.
A headstander is any of several species of South American fish, including Anostomus ternetzi, Anostomus anostomus and members of genus Chilodus from the family Chilodontidae. The name derives from their habit of swimming at a 45° angle, head pointed downwards, as if "standing on their heads".
The croaking gourami is a species of small freshwater labyrinth fish of the gourami family. They are native to still waters in Southeast Asia and are distributed worldwide via the aquarium trade. Croaking gouramis are capable of producing a "croaking" noise using their pectoral fins.
Mesonauta, the flag cichlids, is a small genus of cichlids native to the Amazon, Orinoco, Essequibo, Paraná and Paraguay basins in South America. Mesonauta is included in the subfamily Cichlasomatinae. They occur in various freshwater habitats such as streams and lakes, especially in areas with little water movement and aquatic vegetation. They are generally found in small groups that stay near the water surface. To avoid predators, adults may jump out of the water and juveniles mimic leaves.
Acanthodoras cataphractus more commonly Spiny catfish, is a species of thorny catfish found in rivers of Bolivia, Brazil, Colombia, French Guiana, Guyana, Peru, and Suriname. This species grows to 11.5 cm (4.5 in) in SL. This fish is found in the aquarium trade.
The spotted drum or spotted ribbonfish, is a species of marine ray-finned fish belonging to the family Sciaenidae, the drums and croakers. This species is found in the western Atlantic Ocean.
Abramites hypselonotus – known as the marbled headstander or the high-backed headstander – is a member of the family Anostomidae of the order Characiformes. Under normal fish classifying rules, the marbled headstander would be classified as a surface dweller. In reality marbled headstanders – like all headstanders – inhabit the middle and lower portions of the aquarium. In the wild, head standers are often found face down, tail up in narrow vertical rocky fissures.
Pimelodus pictus, also known as the pictus cat or pictus catfish, is a small member of the catfish family Pimelodidae, native to the Amazon and Orinoco river basins and commonly kept as a pet in freshwater aquariums. Pictus catfish are sometimes mislabeled as Angelicus cats in the aquarium trade, but the latter name actually refers to an unrelated African catfish, the mochokid Synodontis angelica.
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.
Pyrrhulina laeta, known as the half-banded pyrrhulina or half-lined pyrrhulina, is a fish found near Pebas, Peru, and in tributaries of the Ampiyacu River. It is frequently confused with other species.
Pyrrhulina rachoviana is a small species of tropical fish from the family Lebiasinidae named in honor of the German aquarist Arthur Rachow. The type locality is Rosario, Argentina. A species is sold in the aquarium trade under the name Pyrrhulina rachoviana, but was probably imported from Brazil, not Argentina.
The jack-knifefish is a species of marine ray-finned fish belonging to the family Sciaenidae, the drums and croakers. It is native to the western Atlantic Ocean, where its distribution extends along the eastern coasts of the Americas from the Carolinas in the United States to Brazil, including the Caribbean. Other common names include donkey fish and lance-shaped ribbonfish.
Leporinus fasciatus, commonly known as the banded leporinus or the black-banded leporinus, is a species of characin in the family Anostomidae. L. fasciatus is native to the Amazon Basin in South America, but has been introduced into the US states of Florida and Hawaii. It has not been observed from Hawaii as of 2005; the species is thought to have been extirpated in the region.
Gyrinocheilus is the single genus in the family Gyrinocheilidae, a family of small Southeast Asian cypriniform fishes that live in fast-flowing freshwater mountain streams. The species in this genus are commonly called algae eaters. They hold on to fixed objects using a sucker-like mouth, and, despite the name, feed on a wide range of detritus, rather than simply on algae. A "golden" variety of G. aymonieri, the Chinese algae eater or "sucking loach", can be found in many pet shops and fish farms.
Petitella georgiae, the false rummy-nose tetra, is a species of characin found in Amazon Basin in Brazil and Peru. It is a very popular aquarium fish. It resembles two species from its genus, Petitella bleheri and Petitella rhodostoma. It is distributed in the upper Amazon basin in Peru, Rio Purus, Rio Negro, and Rio Madeira basins. Some specimens have a black stripe in the caudal peduncle extending forwards into the body, surmounted above by a thin iridescent gold line; however, whether this feature is a reliable determinant of species identity has yet to be fully ascertained.
Nannostomus mortenthaleri, commonly known as the coral red pencilfish, is a freshwater species of fish belonging to the characin family Lebiasinidae. It is one of the most colourful of the genus, being suffused with a bright coral red colouration over its entire body and fins, in striking contrast to its horizontal jet black stripes. It was originally described as a subspecies of Nannostomus marginatus, but it is now recognised as a species in its own right. Mature males have a thickened anal fin. Maximum length is 29mm.
Polycentrus schomburgkii, also known as the Guyana leaffish is a species of fish belonging to the family Polycentridae. It inhabits fresh and brackish waters, both clear and turbid, of the northeastern part of South America and Trinidad. It reaches a maximum length of 5.5 centimetres (2.2 in).
Tyttocharax madeirae, the blackedge tetra, also known as the bristly-mouthed tetra or the blue tetra, is a small freshwater fish of the family Characidae found in the Amazon basin of South America. It was first caught by Edgar A. Smith in 1912 in Brazil and described by American ichthyologist Henry Weed Fowler in 1913.
Cnesterodon decemmaculatus, the ten spotted live-bearer, is a species of poeciliid native to Argentina and Uruguay.
