Hidden in the darkest crevices lurks a creature capable of delivering a lethal sting—the scorpion. All scorpions are venomous, but only some have medical significance. There are approximately 1400 species of scorpions, and they fall in the class Arachnida (the same as spiders) in the Order Scorpiones. Unlike insects which have six legs, arachnids have eight. Scorpions are nocturnal animals hiding by day in fissures, under stones, or under tree bark. They live in tropical and temperate regions—deserts, forests, mountains, and savannas.
New World scorpions such as Centruroides sculpturatus are found in Arizona, while those from the genus Tityus are found in South America. Old world scorpions, such as Leiurus are distributed throughout northeastern Africa through the Middle East (Egypt, Israel, Jordan, Syria, and Lebanon). The scorpion Leiurus quinquestriatus is sometimes known as the “deathstalker.”
Pincer-like claws are positioned in front of the cephalothorax and are used to catch prey. The scorpion diet consists primarily of insects and arachnids, and rather than hunt prey, scorpions wait for their quarry, detecting them with sensory hairs. The scorpion tail consists of the stinger ending in a barb that contains two poison glands. That’s the business end used to inject the venom into the prey.
There are approximately 1.2 million scorpion stings that occur worldwide each year. Scorpions can sting repetitively since only a fraction of their venom is discharged in a single sting. Once stung, it’s important to immobilize the limb to slow the venom’s spread and reduce the systemic effects. For example, envenomation with L. quinquestriatus (LQ) toxin produces both cardiovascular and neurotoxic complications. Treatment involves supportive medical care and antivenoms. Different scorpion antivenoms exist and are region (geographic species) specific.
So, in the words of Lily Robinson, “The take-home message, my friend, is to make sure you shake out your boots before you put them on.”
*Adapted from Lily Robinson and the Art of Secret Poisoning
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