''Hoplias aimara'', also known as anjumara, traíra, trahira, ''manjuma'', ''anjoemara'' and wolf fish, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of freshwater fish found in the rivers of South America. In

Amazonia The Amazon rainforest, Amazon jungle or ; es, Selva amazónica, , or usually ; french: Forêt amazonienne; nl, Amazoneregenwoud. In English, the names are sometimes capitalized further, as Amazon Rainforest, Amazon Forest, or Amazon Jungle. ...

, the native populations are concerned by high levels of mercury contamination which have been linked to the consumption of contaminated fish. ''H. aimara'' is a good bioindicator of such contamination.Maury-Brachet, R., Gentes, S., Dassié, E. P., Feurtet-Mazel, A., Vigouroux, R., Laperche, V., ... & Legeay, A. (2019)
Mercury contamination levels in the bioindicator piscivorous fish Hoplias aïmara in French Guiana rivers: mapping for risk assessment
'. Environmental Science and Pollution Research, 1-13
résumé
.

Description

This is the largest of the ''Hoplias'' species with specimens caught at a length of , the largest rod and reel record stands at . They can weigh as much as . This species has an elongated cylindrical shape. the colour is basically brown with a lighter base colour, although shades can vary, with a number of vertical patches or stripes. There are normally small spots visible on the upper anterior part of the body including the head, the patterning can vary geographically. The colour can be almost solid black through to pale brownish gold colour with marked dark stripes. Although it seems docile, the fish has been known to attack divers and swimmers, however there is rarely a fatal ending.

Taxonomy

There were thought to be two species of giant trahiras ''Hoplias aimara'' (Valenciennes, 1846) and ''Hoplias macrophthalmus'' ( Pellegrin, 1907), each described from

French Guiana French Guiana ( or ; french: link=no, Guyane ; gcr, label=French Guianese Creole, Lagwiyann ) is an overseas departments and regions of France, overseas department/region and single territorial collectivity of France on the northern Atlantic ...

, study of the

type-specimen In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes th ...

s of each species showed that both names, ''H. aimara'' and ''H. macrophthalmus'', referred to the same

taxon In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

. The Principle of Priority of the

International Code of Zoological Nomenclature The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the ...

therefore means that the name ''Hoplias aimara'' has precedence.George M. T. Mattox, Mônica Toledo-Piza, Osvaldo T. Oyakawa, and J. W. Armbruster , (2006) Taxonomic Study of Hoplias Aimara (Valenciennes, 1846) and Hoplias macrophthalmus (Pellegrin, 1907) (Ostariophysi, Characiformes, Erythrinidae). Copeia: September 2006, Vol. 2006, No. 3, pp. 516-528.

Distribution, habitat and ecology

Across most of northern South America, Brazil, Colombia, Venezuela, Guyana, French Guiana,

Suriname Suriname (; srn, Sranankondre or ), officially the Republic of Suriname ( nl, Republiek Suriname , srn, Ripolik fu Sranan), is a country on the northeastern Atlantic coast of South America. It is bordered by the Atlantic Ocean to the north ...

and the island of

Trinidad Trinidad is the larger and more populous of the two major islands of Trinidad and Tobago. The island lies off the northeastern coast of Venezuela and sits on the continental shelf of South America. It is often referred to as the southernmos ...

. Often found in counter current zones of principal rivers and creeks. It is mainly an ambush predator of fish but also feeds opportunistically on other animals that fall into the water such as terrestrial invertebrates. Attacks on larger vertebrates including humans are unproven. It is active predominantly at dusk and at night. Reproduction takes place at the onset of the rainy season from December to March. Depending on the size, the female can carry around 6,000 to 60,000 eggs. It is known for the quality of its flesh and populations in many more settled parts of its range have been severely depleted due to fishing for food.

Gallery

Image:Hoplias macropthalmus.jpg Image:Hoplias macropthalmus2.jpg

References

{{Taxonbar, from=Q140879 Fish described in 1847 Taxa named by Achille Valenciennes Fish of South America Erythrinidae