A scorpion under a blacklight. In normal lighting this scorpion appears black
Scorpions are any arachnid of the order Scorpionida. They are members of the order Scorpiones within the class Arachnida. There are about 2,000 species of scorpions.
Life and Habits
Scorpions have quite variable lifespans and the actual lifespan of most species is not known. The age range appears to be approximately 4-25 years (25 years being the maximum reported life span in the species Hadrurus arizonensis). Lifespan of Hadogenes species in the wild is estimated at 25-30 years.
Scorpions prefer to live in areas where the temperatures range from 20°C to 37°C (68°F to 99°F), but may survive from freezing temperatures to the desert heat.They are nocturnal and fossorial, finding shelter during the day in the relative cool of underground holes or undersides of rocks and coming out at night to hunt and feed. Scorpions exhibit photophobic behavior, primarily to evade detection by their predators such as birds, centipedes, lizards, mice, possums, and rats.
Scorpions are opportunistic predators of small arthropods and insects. They use their chelae (pincers) to catch the prey initially. Depending on the toxicity of their venom and size of their claws, they will then either crush the prey or inject it with neurotoxic venom. This will kill or paralyze the prey so the scorpion can eat it. Scorpions have a relatively unique style of eating using chelicerae, small claw-like structures that protrude from the mouth that are unique to the Chelicerata among arthropods. The chelicerae, which are very sharp, are used to pull small amounts of food off the prey item for digestion. Scorpions can only digest food in a liquid form; any solid matter (fur, exoskeleton, etc) is disposed of by the scorpion..
Venom
All scorpion species possess poison or venom. Scorpions use their venom to kill or paralyze their prey so that it can be eaten; in general it is fast-acting, allowing for effective prey capture. The effects of the sting can be severe.
Most scorpions are relatively harmless to humans; stings produce only local effects (such as pain, numbness or swelling). A few scorpion species, however, mostly in the family Buthidae, can be dangerous to humans. Among the most dangerous are the deathstalker, which has the most potent venom in the family. The scorpion which is responsible for the most human deaths is the yellow fat-tailed scorpion, of North Africa. Human deaths normally occur in the young, elderly, or infirm; scorpions are generally unable to deliver enough venom to kill healthy adults. Some people, however, may be allergic to the venom of some species. Depending on the severity of the allergy, the scorpion's sting may cause death. A primary symptom of a scorpion sting is numbing at the injection site, sometimes lasting for several days. Scorpions are generally harmless and timid, and only voluntarily use their sting for killing prey, defending themselves or in territorial disputes with other scorpions. Generally, they will run from danger or remain still.
