Chilopod

Centipedes Temporal range: 418–0 Ma PreЄ Є O S D C P T J K Pg N Late Silurian to present
Lithobius forficatus
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Myriapoda
Class:	Chilopoda Latreille, 1817
Orders and Families
Scutigeromorpha Pselliodidae Scutigeridae Scutigerinidae Lithobiomorpha Henicopidae Lithobiidae Craterostigmomorpha Craterostigmidae Scolopendromorpha Cryptopidae Scolopendridae Scolopocryptopidae Geophilomorpha Himantariidae Neogeophilidae Geophilidae Oryidae Linotaeniidae

Centipedes (from Latin prefix , "hundred", and , "foot") are arthropods belonging to the class Chilopoda of the subphylum Myriapoda. They are elongated metameric creatures with one pair of legs per body segment. Centipedes are known to be highly venomous, and often inject paralyzing venom. Despite the name, centipedes can have a varying number of legs, ranging from 30 to 354. Centipedes always have an odd number of pairs of legs. Therefore, no centipede has exactly 100 legs. A key trait uniting this group is a pair of venom claws or forcipules formed from a modified first appendage. Centipedes are predominantly carnivorous.

Their size can range from a few millimetres in the smaller lithobiomorphs and geophilomorphs to about 30 cm (12 in) in the largest scolopendromorphs. Centipedes can be found in a wide variety of environments. They normally have a drab coloration combining shades of brown and red. Cavernicolous (cave-dwelling) and subterranean species may lack pigmentation, and many tropical scolopendromorphs have bright aposematic colours.

Worldwide, an estimated 8,000 species of centipedes are thought to exist, of which 3,000 have been described. Centipedes have a wide geographical range, where they even reach beyond the Arctic Circle. They are found in an array of terrestrial habitats from tropical rainforests to deserts. Within these habitats, centipedes require a moist microhabitat because they lack the waxy cuticle of insects and arachnids, therefore causing them to rapidly lose water. Accordingly, they are found in soil and leaf litter, under stones and dead wood, and inside logs. Centipedes are among the largest terrestrial invertebrate predators, and often contribute significantly to the invertebrate predatory biomass in terrestrial ecosystems. Only one species, Scolopendra cataracta, is known to be amphibious and is believed to hunt aquatic or amphibious invertebrates.