Scorpion, common name for arachnid having a flat, narrow body, two lobsterlike claws, eight legs, and a segmented abdominal tail. Terminating in a venomous stinger supplied by a pair of poison glands, the tail is usually curved upward and forward over the back. About 1400 species of scorpion exist; about 40 of them occur in the United States. Scorpions are usually brown in color and range from about 2.5 to 20 cm (about 1 to 8 in) in length.

Found in warm and dry tropical regions, including the southwestern United States, the scorpion is nocturnal and feeds mainly on spiders and insects. The young are born live and remain with the mother for a short period. When capturing a victim with its claws, the scorpion inflicts a disabling sting with its tail. In most species the sting is painful, but not fatal, to humans, although the sting of one species found in the United States has proved fatal to young children and is potentially fatal to adults. Other areas of the world have more dangerous scorpion species; the poison involved is a neurotoxin, attacking the nervous system.

Scientific classification: Scorpions belong to the order Scorpionida in the class Arachnida. The one potentially deadly species found in the United States is classified as Centruroides sculpturatus.