Scorpions Spiders Mites and Ticks: Arachnida

Physical characteristics: The book scorpion is very small, at 0.10 to 0.18 inches (2.6 to 4.5 millimeters), and looks somewhat like a pear-shaped scorpion without the stinging tail. The front of the body is olive brown to dark red and has no segments. The abdomen is olive green to pale brown and has distinct segments. The body regions are attached to one another. Their tiny claws contain venom glands.

Geographic range: The book scorpion is found throughout most of Europe and the United States.

Habitat: They are commonly found in homes and other buildings, including stables, barns, grain stores, and factories. They are also often found in old books in libraries.

The book scorpion's claws contain venom glands. Prey is grabbed, killed and torn apart with the claws. (Illustration by Bruce Worden. Reproduced by permission.)

Diet: The book scorpion eats insects, mites, and lice. Prey is grabbed, killed, and torn apart with the pedipalps, which contain venom glands. The body fluids of the prey are then sucked into the mouth.

Behavior and reproduction: Books scorpions are sometimes found in large groups, with several dozen individuals. Females often use their pedipalps to grab hold of flying insects, such as house flies, to hitch a ride. Males are less likely to use this method of transportation. Their clawed pedipalps are used primarily for defense, fighting, prey capture, and building nests. Silk produced by glands in the claws is fashioned into a cocoon for molting and winter hibernation.

Book scorpions engage in courtship dances. The male grabs the female's claws and legs and leads her to his sperm packet. Females brood sixteen to forty eggs in a sac attached underneath their bodies. The young resemble the adults but are much paler. They molt three times and take from ten months to two years to reach maturity. They may live three to four years.

Book scorpions and people: Book scorpions eat head lice, mites, ants and other small arthropod pests living in homes and other buildings, but humans seldom notice them at all.

Conservation status: This species is not endangered or threatened. ∎