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''Leporinus obtusidens'' is a South American species of headstander that inhabits the basins of the Paraná River and the Río de la Plata, the Uruguay River, and the São Francisco River (including minor rivers and tributaries like the Bermejo, Pilcomayo, Salí, Juramento, 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 Spanish its common name is ''boga'' (sometimes augmentative ''bogón''); in Brazil 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. ''Leporinus 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 (''leporinus'', "hare-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 ''L. macrocephalus'', only recently classified as a separate species). ''Leporinus obtusidens'' is an omnivore: it eats water plants, crabs and river snails. However, it prefers grain and seeds (wheat and maize), 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 and the sábalo. 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 ) * (''Los Peces Que Tenemos'' ) * (Pesca & náutica: ''Nuestros peces'' ) * (''Pesca en Argentina'' ) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Leporinus obtusidens」の詳細全文を読む スポンサード リンク
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