Centipede. Coloured scanning electron micrograph (SEM) of the underside of a centipede. Centipedes (class Chilopoda) are arthropods with elongated bodies and one pair of legs per segment. The head is at left, with two branching antennae that are sensory structures. Centipedes are swift nocturnal predators that kill their prey using powerful venom administered from forelegs that have been modified to function as fangs (left, between the antennae). They feed on worms and insects, though the larger (tropical) ones (up to 30 centimetres long) hunt small birds, lizards and mammals.