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Uropygi (schizomids, whipscorpions; subphylum Chelicerata, class Arachnida) Order of small to medium-sized (up to 7.5 cm long) arachnids in which the prosoma is not divided dorsally, and the large pedipalpi are held flexed and parallel to the ground. The last abdominal segment bears a many-segmented flagellum. Whipscorpions possess anal spray glands used in defence, the secretions being largely acetic acid with some caprylic acid to aid cuticle penetration. Usually brownish and flat, whipscorpions live under stones, stump bark, and rubbish, and prey on small arthropods (e.g. crickets) and small toads. Schizomids are smaller, up to 7 mm long, and possess a very short, terminal, abdominal flagellum. The pedipalpi are leg-like and raptorial, not chelate. The two small chelicerae are tipped by small pincers. As in the whipscorpions, there are anal glands, and schizomids live under stones and leaf-litter. Uropygids possess sensory trichobothria, slit organs, and pits, inhabit the tropics and subtropics, and have reproduction similar to that of scorpions. There are 75 known species of whipscorpion and more than 50 known species of schizomid.