''Megaleporinus obtusidens'' is a

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

n species of

headstander A headstander is any of several species of South American fish, including ''Anostomus ternetzi'', ''Anostomus anostomus'' (family Anostomidae) and members of genus ''Chilodus'' from the family Chilodontidae. The name derives from their habit of ...

that inhabits the basins of the

Paraná River The Paraná River ( es, Río Paraná, links=no , pt, Rio Paraná, gn, Ysyry Parana) is a river in south-central South America, running through Brazil, Paraguay, and Argentina for some ."Parana River". Encyclopædia Britannica. Encyclopædia Br ...

and the Río de la Plata, the Uruguay River, and the

São Francisco River The São Francisco River (, ) is a large river in Brazil. With a length of , it is the longest river that runs entirely in Brazilian territory, and the fourth longest in South America and overall in Brazil (after the Amazon, the Paraná and t ...

(including minor rivers and tributaries like the Bermejo, Pilcomayo, Salí,

Juramento Juramento is a municipality in the north of the Brazilian state of Minas Gerais. the population was 4,345 in a total area of 432 km². It became a municipality in 1953. Juramento is located 42 km to the southeast of Montes Claros on ...

, Dulce, and Uniguay). It may be found in the main courses and streams, as well as in lakes and lagoons; it often shelters among stones and aquatic vegetation. In

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

and

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

its common name is ''boga'' (sometimes

augmentative An augmentative (abbreviated ) is a morphological form of a word which expresses greater intensity, often in size but also in other attributes. It is the opposite of a diminutive. Overaugmenting something often makes it grotesque and so in so ...

''bogón''); in

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

it is known as ''piapara''. There is also a variant called ''piava'' and another called ''tres puntos'' ("three dots"). This species is also known by the technical synonym ''Curimatus obtusidens''. The common name ''boga'' is applied to many other species of fish, usually unrelated to this one. ''Megaleporinus obtusidens'' has an elongated wide body, with a comparatively small head and a blunt mouth; its teeth are reminiscent of the incisors of '' Lagomorpha'', whence the name of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

(''leporinus'', "

hare Hares and jackrabbits are mammals belonging to the genus ''Lepus''. They are herbivores, and live solitarily or in pairs. They nest in slight depressions called forms, and their young are able to fend for themselves shortly after birth. The ge ...

-like", as in '' Leporidae''). Its basic colour is a light greenish-gray, with three rounded dark spots in mid-flank, which may not be visible in some specimens. In young individuals there are also eight broad vertical streaks, joined in the back and coming down to the middle line. The back, as usual in this habitat, is darker than the belly. The length and weight of the individuals are extremely variable according to the area, probably influenced by different feeding habits, opportunities and exploitation, as well as local sub-specific variants. In the Río de la Plata ''L. obtusidens'' is reported as weighing an average of 2 kg, with a maximum of 4 kg; in the upper course of the Paraná River it is about 4.5 kg; and in the middle course of the Paraná there are specimens of ''boga'' over 6 kg (with exceptionally developed ones over 8 kg). Adult individuals are reported between 40 and 80 cm long. The larger fish probably belong to other species of ''Leporinus'' (either ''L. friderici'', which is still not very well known, or ''Megaleporinus macrocephalus'', only recently classified as a separate species). ''Megaleporinus obtusidens'' is an

omnivore An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutr ...

: it eats water plants,

crab Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the ...

s and river

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastro ...

s. However, it prefers grain and

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

s (

wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...

and

maize Maize ( ; ''Zea mays'' subsp. ''mays'', from es, maíz after tnq, mahiz), also known as corn (North American and Australian English), is a cereal grain first domesticated by indigenous peoples in southern Mexico about 10,000 years ago. Th ...

), and it often gathers in large banks near ports, where cargo ships drop grains into the water. It is preyed upon by larger fish like the

surubí ''Pseudoplatystoma'' is a genus of several South American catfish species of family Pimelodidae. The species are known by a number of different common names. They typically inhabit major rivers where they prefer the main channels and tend to sta ...

and the dorado. It prefers warm waters and reproduces in spring and summer, starting at 2 years of age.

References

* * * Cordiviola de Yuan, E. and C. Pignalberi de Hassan, 1985. Fish population in the Paraná River: lentic environments of Diamante and San Pedro areas (Argentine Republic). Hydrobiologia 127:213-218.
Migratory fishes of the Paraguay-Paraná basin excluding the upper Paraná basin
*

*

*

{{Taxonbar, from=Q533807 Fish of South America Anostomidae Freshwater fish of Argentina Paraná River Fish of the São Francisco River basin Taxa named by Achille Valenciennes Fish described in 1847 Taxobox binomials not recognized by IUCN