Centipedes are carnivorous and predacious, immobilizing their prey, usually consisting of smaller arthropods, with the aid of their fangs. The body is composed of a head region bearing a pair of antennae, a pair of mandibles, and two pairs of maxillae, and a trunk region with one pair of legs on each segment. Chilopods are found throughout the globe in tropical as well as temperate climates. There are about 8,000 species belonging to class Diplopoda, which comprises the millipedes and is found worldwide. The head region has a pair of antennae, a pair of mandibles, and two pairs of maxillae that are usually fused into a single mouthpart, the chilognatharium.
Millipedes possess a tracheal system for respiration.
They are herbivores or scavengers on dead plant material. Many are protected by glands that produce toxic or unpleasant compounds. There are about 500 known species belonging to class Pauropoda. They are elongated and have 9-11 pairs of legs, but they have no trachea and no heart. Class Symphyla Members of class Symphyla are rapid runners that range in length from 1 to 4 in.