Characiformes is an order of ray-finned fish, comprising the characins and their allies. Grouped in 18 recognized families, more than 2000 different species are described, including the well-known piranha and tetras.
A piranha or piraña is any of a number of freshwater fish species 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.
Serrasalmus is a genus of piranhas. They are collectively known as pirambebas; the "typical" piranhas like the piraya piranha are nowadays placed in Pygocentrus. Like all piranhas, Serrasalmus are native to South America.
Pygocentrus is a genus of the piranha family Serrasalmidae. All species are native to tropical and subtropical South America. All the species are predatory, scavengers and may form large schools. The famous red-bellied piranha, Pygocentrus nattereri, is one of four species in the genus.
Pygocentrus piraya, often called the piraya piranha or San Francisco piranha, and sometimes sold as the man-eating piranha, is a large, aggressive piranha from the São Francisco River basin in Brazil.
Pacu is a common name used to refer to several species of omnivorous South American freshwater serrasalmid fish related to piranhas. Pacu and piranha do not have similar teeth, the main difference being jaw alignment; piranha have pointed, razor-sharp teeth in a pronounced underbite, whereas pacu have squarer, straighter teeth and a less severe underbite, or a slight overbite. Pacu, unlike piranha, mainly feed on plant material and not flesh or scales. Additionally, the pacu can reach much larger sizes than piranha, at up to 1.08 m in total length and 40 kg (88 lb) in weight.
Serrasalmus geryi, known as the violet line piranha or Gery's piranha, is a species of piranha of the family Serrasalmidae. It is found in the lower Tocantins and Araguaia Rivers of Brazil. The species is notable for being the one of only the members of the genus Serrasalmus that can coexist with others of the same species in captivity, however caution is advised. Gery's Piranha reaches sizes up to 12 inches in length. As of 2018, it is classified as Least Concern by the International Union for Conservation of Nature.
The Serrasalmidae (serrasalmids) are a family of characiform fishes, recently elevated to family status. It includes more than 90 species. The name means "serrated salmon family", which refers to the serrated keel running along the belly of these fish. Fish classified as Serrasalmidae are also known by these common names: pacu, piranha, and silver dollar. These common names generally designate differing dental characteristics and feeding habits.
The tiger catshark is a species of catshark, belonging to the family Scyliorhinidae. It is found over sandy areas and near reef peripheries off South Africa and perhaps Mozambique, from close to shore to usually no deeper than 100 m (330 ft). Reaching a length of 50 cm (20 in), this small, slim shark has a broad, flattened head with an upturned snout tip. It can additionally be identified by its dorsal colour pattern of ten dark brown saddles on a yellowish brown background.
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 tambaqui is a large species of freshwater fish in the family Serrasalmidae. It is native to tropical South America, but kept in aquaculture and introduced elsewhere. It is also known by the names black pacu, black-finned pacu, giant pacu, cachama, gamitana, and sometimes as pacu.
The wimple piranha,, is a specialized, South American species of piranha that feeds on fish scales. There is some debate over whether or not this species is considered a true piranha. If considered a true piranha, it would be the smallest species of piranha in the world.
Pristobrycon is a genus of piranhas from the Orinoco and Amazon Basins, as well as rivers in the Guianas.
Piaractus brachypomus, the Red-Bellied Pacu or Pirapitinga, is a large species of pacu, a close relative of piranhas and silver dollars, in the serrasalmid family. It is native to the Amazon basin in tropical South America, but it formerly included populations in the Orinoco, which was described in 2019 as a separate species, P. orinoquensis. Additionally, P. brachypomus is widely farmed and has been introduced to other regions. In South Florida they are invasive in rivers, canals or lakes.
Pristobrycon maculipinnis, sometimes known as the marbled piranha, is a species of serrasalmid endemic to Venezuela.
Pristobrycon calmoni is a South American species of serrasalmid fish.
Megapiranha is an extinct serrasalmid characin fish from the Late Miocene Ituzaingó Formation of Argentina, described in 2009. The type species is M. paranensis. It is thought to have been about 71 centimetres (28 in) in length and 10 kilograms (22 lb) in weight. The holotype consists only of premaxillae and a zigzag tooth row; the rest of its body is unknown. This dentition is reminiscent of both the double-row seen in pacus, and the single row seen in the teeth of modern piranhas, suggesting that M. paranensis is a transitional form. Its bite force is estimated between 1,240–4,749 N (279–1,068 lbf).
Tometes is a genus of fish in the family Serrasalmidae found in fast-flowing rivers in northern South America. Adults of all seven species in this genus are phytophagous, feeding primarily on aquatic plants in the family Podostemaceae.
Pygocentrus palometa is a species of piranha endemic to Venezuela, where it is restricted to the Orinoco Basin. Although recognized by FishBase, the scientific name may be a nomen dubium.
Pseudoprepotherium is an extinct genus of sloths of the family Mylodontidae. It was widespread across northern South America during the Early to Late Miocene epoch around 21 to 5.3 million years ago. Fossils of the animal have been found in Brazil, Venezuela, and Peru. Pseudoprepotherium lived in a tropical climate with a water-rich environment. Their known remains are limited to limb bones, except for a few skulls and teeth. Based on these remains, they were most likely medium to large-sized mylodontid. The genus was described in 1961 and currently contains three species, which were originally assigned to the genus Prepotherium.
