Centipedes are elongated metameric creatures with a pair of legs per body segment. Despite the name, which consists of Latin words centi- (meaning "hundred") and pedis (meaning "foot") , centipedes usually have a varying number of legs, ranging from 30 to 354. They always have an odd number of pairs of legs. As 50 is an even number, centipedes can't actually have exactly 100 legs. Sometimes leg pairs are added in the process of their development. A distinguishing feature of all centipedes is a pair of venom claws or forcipules (pincer-like forelegs) formed from a modified first appendage. Most of them are predators. Centipedes sometimes lose their legs during a fight or to escape it and then regenerate them.

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