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any of about 6,000 species of bony fishes belonging to the superorder Ostariophysi, including the majority of freshwater fishes throughout the world. Familiar representatives of this group are the minnows, suckers, characins, loaches, gymnotid "eels," and innumerable catfishes. The 31 recognized families of catfishes constitute the order Siluriformes, the remaining 26 families the order Cypriniformes. Humans consume huge quantities of these fishes for food and derive pleasure from the beauty of tropical aquarium fishes. A few harmful species can inflict painful injuries; some others serve as intermediate hosts for parasites of humans. Strange and fascinating behaviour is exhibited by many of these fishes-nest building, oral incubation, egg laying in mollusk shells, walking and flying, air breathing, production of sound and electricity, and communication by chemical secretions