The black piranha (''Serrasalmus rhombeus''), also known as the redeye piranha, white piranha, spotted piranha or yellow piranha, is a species of freshwater

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

, a

piranha A piranha (, or ; ) is any of a number of freshwater fish species in the subfamily Serrasalminae, of the family Serrasalmidae, in the order Characiformes. These fish inhabit South American rivers, floodplains, lakes and reservoirs. Although ...

from the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Serrasalmidae The Serrasalmidae (serrasalmids) are a family of characiform fishes native to freshwater habitats of South America. They include more than 90 species. The name means "serrated salmon family", which refers to the serrated keel running along the ...

. It is found in northern South America. It is the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

of the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

Serrasalmus ''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. These fis ...

''.

Taxonomy

The black piranha was first formally described in 1766 as ''Salmo rhombeus'' with the type locality given as

Brokopondo Brokopondo is the capital town of the Brokopondo District, Suriname. It is located on the west shore of the Suriname river, just north of the Afobaka dam, 105 kilometers (65 miles) south-east of Suriname capital city of Paramaribo. Brokopondo can b ...

on the

Suriname River The Suriname River ( Dutch: ''Surinamerivier'') is long and flows through the country of Suriname. Its sources are located in the Guiana Highlands on the border between the Wilhelmina Mountains and the Eilerts de Haan Mountains (where it is kn ...

in Surinam. When

Bernard Germain de Lacépède Bernard-Germain-Étienne de La Ville-sur-Illon, comte de Lacépède or La Cépède (; 26 December 17566 October 1825) was a French natural history, naturalist and an active freemason. He is known for his contribution to the Comte de Buffon's g ...

created the genus ''

'' in 1803 the only species he placed in it was ''Salmo rhombeus'', so this species is the type species of its genus. The morphological differences between populations suggest that ''S. rhombeus'' is a

species complex In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

, but molecular work to confirm this has yet to be undertaken.

Distribution

The black piranha is found in northern South America, east of the

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

. They are found in the drainage systems of the

Amazon Amazon most often refers to: * Amazon River, in South America * Amazon rainforest, a rainforest covering most of the Amazon basin * Amazon (company), an American multinational technology company * Amazons, a tribe of female warriors in Greek myth ...

and

Orinoco The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers approximately 1 million km2, with 65% of it in Venezuela and 35% in Colombia. It is the List of rivers by discharge, f ...

as well as the

Essequibo River The Essequibo River (; originally called by Alonso de Ojeda; ) is the largest river in Guyana, and the largest river between the Orinoco and Amazon River, Amazon. Rising in the Acarai Mountains near the Brazil–Guyana border, the Essequibo flows ...

and other rivers of the

Guiana Shield The Guiana Shield (; ; ; ) is one of the three cratons of the South American Plate. It is a 1.7 billion-year-old Precambrian geological formation in northeast South America that forms a portion of the northern coast. The higher elevations on ...

and the coastal rivers of northeastern Brazil. It has been introduced to

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

but is now

extirpated Local extinction, also extirpation, is the termination of a species (or other taxon) in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions mark a chan ...

Description

The black piranha is the largest species of piranha. It has a distinctively, rhombus-shaped body, solidly coloured from grey through to nearly black. Whatever the body colour, this species has red eyes. The colour of juveniles can be more mottled than in adults. As they mature their silvery body becomes less mottled and changes to a darker grey or black colour. How dark the fish become depends on the local water conditions; fish in Peru appear to be the darkest and may be almost jet black. The maximum recorded

fish measurement Fish measurement is the measuring of individual fish and various parts of their anatomies, for data used in many areas of ichthyology, including taxonomy and fishery biology. Overall length Standard length (SL) is the length of a fish measured ...

standard length is , although a more normal length is around , and they attain a maximum weight of .

Habitat and biology

The black piranha occurs in a wide variety of habitats but the adults have a preference for the larger, deeper river channels where they normally hunt for prey either in deep stretches or in the vicinity of rapids. The juveniles are most frequently recorded in stiller stretches where there is thick submerged or marginal vegetation. Paler coloured fish tend to be found in turbid white waters, while in clear or dark waters, dark fish predominate. These fish are opportunistic and

omnivorous An omnivore () is an animal that regularly consumes significant quantities of both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize ...

feeders which will eat plants, fallen fruits and animals smaller than themselves such as insects and small fishes. They will also eat the scales and fins which they can nip off other fishes. They are well known scavengers, and feed on carcasses within the river. This is not a sociable species and normally lives solitarily. At least when breeding they defend an area around the nest which is placed among thick vegetation.

References

{{Taxonbar, from=Q2038575 Serrasalmidae Piranhas Fish of South America Fish described in 1766 Taxa named by Carl Linnaeus