Three families of centipedes form the order Scutigeromorpha. These centipedes often have 15 body segments, with one pair of legs in each of them. The European species Scutigera coleoptrata has been introduced in North America, where is generally found in moist places near houses. These centipedes have long legs and are carnivores.
The Lithobiomorpha are short-bodied centipedes that comprise two families with about 1,500 species. The genus Lithobius, which include the so-called brown or stone centipedes, has more than 300 species alone. The Craterostigmomorpha has only one species Craterostigmus tasmanianus, which is found in Tasmania and New Zealand. This centipede has external pores, used to secrete a sticky substance and repel predators.
Geophilomorpha is the only order containing slow-moving centipedes, which are adapted to burrow on the ground instead of running, when they feel threatened. It is also the only order that features from 27 to 191 pairs of legs. Geophilomorpha is a diverse group of centipedes that do not have eyes, with 14 families, 180 genera and about 1,100 known species. They measure from 0.2 inch to 7.8 inches in length.
Native Scolopendromorpha in North America include eight genera and 21 species, some of which can attack and feed on small vertebrates, such as snakes, frogs, mammal and birds. These centipedes have bodies with 21 or more segments, having one pair of legs in every segment. The genus Scolopendra contains the largest centipedes, including the Sonora desert centipede (S. polymorpha), featuring a 7-inch-long body and the Amazonian giant centipede (S. gigantea), which can reach 12 inches in length.