3 family worldwide, all represented in NA; in our area, 27 spp. (incl. 6 introduced) in 9 genera; worldwide, 33 genera and ~600 described (estimated 800) spp.(1)(2)
21 (Scolopendridae, except Scolopendropsis, and Cryptopidae) or 23 pairs of legs (Scolopocryptopidae)(1)
in warmer regions worldwide; in our area much more diverse towards the south, esp. in states bordering Mexico; two spp. reach Canada (so. ON, BC) and one, so. AK(2)
They can bite and also pinch with their last pair of legs. Bites may cause intense pain, swelling, discoloration, numbness, and necrosis, and require medical assistance, although there are no really dangerous, deadly centipedes, and no confirmed human fatalities.(1)
Cloudsley-Thompson J.L. (1958) Spiders, scorpions, centipedes, and mites. (revised ed. 1968). Pegamon, Oxford. 228 pp.
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