Hundred-footers never have exactly one hundred walking legs
Centipedes (Chilopoda) are predatory myriapods with one pair of legs per body segment and a name that promises a hundred feet. Sizes run from a few millimetres to about 30 cm in giant scolopendromorphs. Many species are blind to form, sensing only light and dark with ocelli.
Modified front limbs become venomous forcipules that seize prey. Generalist carnivores, they haunt moist microhabitats from rainforests to deserts worldwide. Antennae, mandibles, and two maxillae pairs equip a rounded or flattened head for night hunting.
Despite the Latin boast, leg counts vary by species and growth; the brand is metaphor, the venom is not.
Leave a damp log unturned and a chilopod may already be measuring the dark with more legs than its name admits.
The venom claws, called forcipules, are unique to centipedes: a converted first pair of legs forming pincers just behind the head, not true mouthparts. The body has at least fifteen segments, most carrying a single pair of legs, which is one way to tell centipedes from millipedes. At the rear, the final pair become ultimate legs used for anything but walking; Alipes species rasp their leaf-shaped ones to startle predators. Mating involves no copulation, since the male leaves a sperm packet for the female to collect, and females look after their eggs and young. They outlive insects: Lithobius forficatus may reach 5 or 6 years and Scolopendra subspinipes more than 10. Their usual diet runs to earthworms, fly larvae and springtails, but big Scolopendra and Ethmostigmus can overpower prey larger than themselves, vertebrates included. Some species defend themselves with sticky secretions, those of scolopendromorphs containing hydrogen cyanide, and Arizona's giant desert centipede wears black and orange that may warn of its toxicity.
Source: Centipede
