Scorpions Spiders Mites and Ticks: Arachnida

Physical characteristics: Whip spiders, or tailless whip scorpions, grow as long as 1.2 inches (30.4 millimeters). They lack the ability to produce silk and do not have venom glands. Their claws fold into a spiny basket, used to capture and hold prey. Young whip scorpions have reddish pedipalps and striped legs; the adults are uniformly brownish. The undivided carapace is wider than it is long. The first pair of legs is long, slender, and whiplike. Packed with special sensory structures, these legs are used not for walking but as antennae, or sense organs. The abdomen lacks a tail or defensive glands. The front of the body and abdomen are attached to each other by a narrow waist.

Geographic range: These scorpions range through Belize, Guatemala, and Costa Rica.

Tailless whip scorpions live in cracks and crevices between rocks, under loose tree bark, at the base of tree trunks, or inside animal burrows, caves, and tree holes. (Illustration by Bruce Worden. Reproduced by permission.)

Habitat: Tailless whip scorpions live in cracks and crevices (KREH-vuh-ses) between rocks, under loose tree bark, at the base of tree trunks, or inside animal burrows, caves, and tree holes.

Diet: Tailless whip scorpions prey on small crickets, moths, and millipedes but usually avoid scorpions, centipedes, large spiders, and most ants.

Behavior and reproduction: Tailless whip scorpions are solitary animals. They are often found sitting quietly on tree trunks, waiting for insects to pass by and waving their whiplike pedipalps back and forth. Tailless whip scorpions are gentle creatures. They are very shy and run quickly when threatened. If they are attacked, they will use their spiny pedipalps as defensive weapons.

When females are nearby, males will often engage other males in combat, locking their mouthparts and claws together in battles that may last more than an hour. Males and females engage in a courtship dance that includes lots of touching and brief grabbing with the pedipalps. Once the male is accepted as a mate, he deposits a sperm packet and guides the female over it. The female lays twenty to forty eggs several months after mating. The eggs are carried underneath the body of the female until they hatch in about three or four months. After hatching, the young crawl up on the mother's back, where they remain for about a week, until they molt. They molt once or twice a year until they reach maturity. Tailless whip scorpions continue molting and growing throughout their adult lives.

Tailless whip scorpions and people: Tailless whip scorpions lack venom and are quite harmless.

Conservation status: These scorpions are not endangered or threatened. ∎