Scorpions Spiders Mites and Ticks: Arachnida

Physical characteristics: Emperor scorpions are shiny blue, black to greenish black, and measure 5 to 8 inches (127 to 203 millimeters) in length, including the tail. They weigh up to 1.1 ounces (35 grams), although pregnant females may weigh as much as 1.4 ounces (40 grams). The males are similar in appearance to the females, but are slightly smaller and lighter-bodied. The powerful reddish-brown claws are rough in texture. The claws, body, and tail are covered with sensory hairs. Underneath the abdomen, behind the last pair of legs, is a pair of comblike pectines. The pectines of males are longer than those of females. The six-segmented tail ends in a curved stinger.

Emperor scorpions are found in the western African countries of Senegal, Guinea-Bissau, Guinea, Ivory Coast, Sierra Leone, Ghana, Togo, Democratic Republic of Congo, Nigeria, Gabon, and Chad. (Illustration by Bruce Worden. Reproduced by permission.)

Geographic range: This species is found in the western African countries of Senegal, Guinea-Bissau, Guinea, Ivory Coast, Sierra Leone, Ghana, Togo, Democratic Republic of Congo, Nigeria, Gabon, and Chad.

Habitat: This species prefers living in hot, humid habitats. They live in abandoned burrows of other animals or will dig their own. Individuals will also take shelter beneath rocks, logs, and tree roots.

Diet: They will hunt almost any animal smaller than themselves. Their food includes crickets, insects, other arachnids, mealworms, and millipedes. They will even catch and kill small mice and lizards. Emperor scorpions seldom run down their prey, preferring instead to ambush unsuspecting insects and other small animals that wander nearby. Digestive chemicals are used to turn their victim's tissues into liquid, which is then sucked into the mouth.

Behavior and reproduction: Emperor scorpions search for mates and hunt for food at night. They detect the size and location of prey mainly through vibrations in the ground and in the air. Hungry scorpions move slowly forward, with open claws held out, and tail raised forward over the body. Young scorpions grasp their prey with their claws and quickly sting it. Larger adults crush and kill their victims with their large and powerful claws. Adults are unusually calm and very slow to sting in defense and seldom inject venom when they do.

Adult males spend most of their time looking for mates. During courtship the male uses his claws to grasp those of the female. He guides her to a hard surface where he deposits his sperm packet. He then pulls the female over the sperm packet so she can pick it up with her reproductive organs. The male leaves soon after courtship is completed to avoid being killed and eaten by a hungry female.

The female gives live birth. The young are carried inside her body from seven to nine months. Anywhere from nine to thirty-five pale white scorpions are born, one after the other. They will climb up on the mother's back and remain there until their first molt. They molt about seven times in four years before reaching adulthood. Adult females often continue to live with their young and will sometimes eat them if other kinds of food are not available. The bodies of young scorpions become darker as they grow. Their total life span is about eight years.

Emperor scorpions and people: Although large in size, emperor scorpions are not considered dangerous to healthy humans. The venom is very mild, but the sting can still be painful. Young scorpions and adult females are more likely to sting than adult males. Larger individuals can deliver a painful pinch with their claws. They are commonly sold as pets and are frequently used in films as "deadly" animals.

Conservation status: This species is not listed by the World Conservation Union (IUCN). However, because thousands of individuals are collected and sold in the pet trade every year, they have been listed as Threatened on Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Their populations are being monitored to prevent over collecting. ∎