Estimated ca. 8,000 spp. globally (less than 3,000 described), arranged into 5 orders (4 in NA) and 23 families (40 or more species in NA, at least 8 introduced species)(1)(2)
10-270+ mm worldwide; in our area, Scolopendra heros is the largest species, reaching ~150 mm
Antennae large; one pair of legs per body segment (15-191 pairs, always an odd number); the last legs extend backwards. All possess “poison claws” (also called “prehensors” or “forcipules”) beneath the head. Most centipedes run fast and can bite, but members of Geophilomorpha are rather sluggish.(1)
All subarctic environments; abundant in deserts(1); moist areas such as leaf litter, under logs or rocks.
Primarily smaller arthropods, but large-bodied representatives of the order Scolopendromorpha are known to attack and feed on bats, small mammals, snakes, frogs/toads, and birds; prey is killed by venom injected through the poison claws(1)
Larger species can inflict a painful bite on humans, but only if handled. The bite of a large centipede can be painful to an adult and dangerous to a small child.(3)
Millipedes have two pairs of legs per body segment, and the last pair does not extend backwards behind the body. In addition, millipedes have small antennae, are unable to run fast, and cannot bite.
Bonato et al. (2010) A common terminology for the external anatomy of centipedes (Chilopoda). ZooKeys 69: 17–51. (Full Text)
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