Ключевые слова: actinopterygii, amazon, amazon river, america, american, animal, animals, aquarium, aquarium fish, brazil, characiformes, fauna, fish, fresh water, fresh water fish, freshwater, freshwater fish, lake, natural, nature, one, one animal, one fish, orinoco, paraguay, parana, piranha, piranhas, pygocentrus, pygocentrus nattereri, red bellied piranha, red piranha, redbellied piranha, rio de la plata, rio machado, rio negro, rio paraguay, rio parana, river, serrasalmidae, serrasalmus, serrasalmus nattereri, south america, south american, swim, swimming, underwater, water, wild, wild animal, wild life, wildlife, zoo,