scorpion

scorpion, any arachnid of the order Scorpionida with a hollow poisonous stinger at the tip of the tail. Scorpions vary from about 1/2 in. to about 6 in. (1–15 cm) long; most are from 1 to 3 in. (2.5–7.6 cm) long. They are predominantly tropical or subtropical, but some species live in temperate regions. During the day they hide in crevices or under objects, emerging at night to feed, mostly on other arthropods. The body is composed of a prosoma (head) covered by a solid protective covering, or carapace, and a segmented opisthosoma (body) divided into a broader mesosoma and a narrower metasoma, which ends in a sting. There are six pairs of appendages located on the prosoma: short, pincerlike appendages called chelicera, which are used to tear up food for swallowing; large appendages called pedipalps, equipped with powerful pincers used to grasp prey (which is then immobilized by stinging if necessary); and four pairs of walking legs. The first segment of the opisthosoma has vestigial appendages in the form of a genital opening (operculum), and the second segment bears unique, comblike sensory appendages known as pectines. The next four opisthosomal segments each bear a pair of respiratory structures known as book lungs, which open into the body by way of a hole, or spiracle. The metasoma is carried high in the air, in preparation for a quick stinging thrust. Although scorpion stings are painful, they are not usually dangerous to humans. Exceptions are the greatly feared scorpion Androctonus australis of the Sahara Desert, whose sting causes death in 6 to 7 hr if the victim is not treated with antivenin, and several species of the genus Centruroides, found in Mexico, which have been responsible for the deaths of a number of persons, mostly children. The scorpion neurotoxin causes convulsions; death results from respiratory or cardiac failure. Complex courtship rituals precede mating. The young scorpions are born alive and are carried for a time by the mother, leaving her after the first molt. About a year is required to reach maturity. Scorpions are classified in the phylum Arthropoda, class Arachnida, order Scorpionida.

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scorpion

Any of some 1,300 nocturnal arachnid species (order Scorpionida, subphylum Chelicerata) having a slender body, a segmented tail tipped with a venomous stinger, and six pairs of appendages. The small first pair tear apart insect and spider prey. Strong, clawlike pincers on the large second pair, held horizontally in front, are used as feelers and for grasping prey while sucking the tissue fluids. The last four pairs, each with a pincer, are walking legs. The venom is either a hemotoxin that, in humans, causes swelling, redness, and pain or a neurotoxin that may cause convulsions, paralysis, cardiac irregularities, and death. Most scorpions will sting a human only if provoked. Nocturnal hunters, most species are tropical or subtropical.

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scorpion

1. any arachnid of the order Scorpionida, of warm dry regions, having a segmented body with a long tail terminating in a venomous sting

2. false scorpion any small nonvenomous arachnid of the order Pseudoscorpionida (or Chelonethida), which superficially resemble scorpions but lack the long tail

3. any of various other similar arachnids, such as the whip scorpion, or other arthropods, such as the water scorpion

4. Old Testament a barbed scourge (I Kings 12:11)

5. History a war engine for hurling stones; ballista

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Scorpion - Twenty tools that can be used to construct specialised programming environments. The Scorpion Project was started by Prof. Richard Snodgrass <rts@cs.arizona.edu> as an outgrowth of the SoftLab Project (which produced the IDL Toolkit) that he started when he was at the University of North Carolina. The Scorpion Project is directed by him at the University of Arizona and by Karen Shannon at the University of North Carolina at Chapel Hill. Version 6.0 runs on Sun-3, Sun-4, VAX, Decstation, Iris, Sequent, HP9000. See also Candle. ftp://cs.arizona.edu/scorpion/. Mailing list: info-scorpion-request@cs.arizona.edu. E-mail: <scorpion-project@cs.arizona.edu>.