Opiliones(redirected from Opilone)
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(also Phalangida), an order of arthropods of the class Arachnida. The body length is 1–22 mm. The animals resemble spiders, but unlike the latter, they have a segmented abdomen joined to the prosoma by a broad base. The first pair of oral extremities are chelate chelicerae that lack poison glands; the pedipalps are short. The walking legs are very long and slender and may be easily torn off. Breathing is by means of tracheae. Of the more than 2,400 species, 72 are found in the USSR. The arthropods live on the forest floor, under the bark of trees; they are often found on fences and various other structures. The animals are nocturnal predators.