Scorpion
Introduction
This common name comes from the order name. Scorpions are nuisance pests, and also are of medical importance because of their stings. Their stings can result in a mild
wasp-like sting, which can be complicated by an allergic reaction, and can be fatal in rare instances. Distribution in the United States is primarily in the arid Southwest
and also in the South, with rare occurrences above a line from Baltimore to St. Louis to Salt lake City to San Francisco. However, in the West they are known as far north as
British Columbia. About 70 species occur in the United States.
Recognition
Adults are about 2-4 inches long. Body form characteristic, cephalothorax elongated and dorsally shieldlike abdomen distinctly segmented, anteriorly elongated with the last five segments
taillike, and ending in a sting usually curved upward. Cephalothorax with anterior pedipalps large and pincerlike, with small chelicerae between their base; eyes 0-12 usually
two dorsal submedian eyes and one to five eyes on each front lateral corner; four pairs of legs; one pair ventral comblike sensory structures just posterior of last pair of coxae; and four pairs
of central spiracles.
Habits
Scorpions are nocturnal feeders. They feed mostly on insects and spiders, but they can be cannibalistic. After large or active prey is caught in the pedipals, it is stung
repeatedly. They chelicerae then macerate the food into tiny particles which are packed between the coxae of the pedipals, and a liquifying secretion is added. The scorpion
then ingests the "juice" produced and the resulting dry pellet is discarded. If water is available, they can survive for months without food.
During the day, scorpions usually hide either in or beneath something. Outside, it may burrow, under a rock, log, or debris, etc. This behavior helps to conserve water loss.
Around structures, scorpions usually are found in crawl spaces and in the attic, which they enter via the wall voids. They favor attics with air-conditioning ducts which provide
cool temperatures and more harborage; otherwise, they move downward as the temperature increases to about 100 degrees F. If door thresholds are missing and/or unscreened windows
are left open, they may enter directly into the living space. They seek water and can sometimes be found in sinks and bathtubs in the morning because they could not climb out. When
sunrise occurs, scorpions seek shelter in the first available harborage, which may be in shoes, pants/shirts/jackets on a chair, folded blankets, etc. Ground scorpions frequently
burrow into children's sand boxes or gravel banks where they can remain buried for up to six months.
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