The Emperor or Imperial scorpion (Pandinus imperator) is a great starting point for those that are interested in keeping scorpions. They are a large, docile, and hardy species that has only a mildly venomous sting. Although they are relatively harmless and their venom can be compared to that of a bee sting, care must always be taken when interacting with any animal that has the potential to cause an adverse reaction from a bite or a sting and handling is not recommended especially for the novice. It is the most popular species available in the pet trade and although availability of this species has recently diminished, it is still widely sought after and kept by many enthusiasts.
Scorpions belong to the class of invertebrates known as Arachnida, making them a relative of tarantulas and spiders. Unlike insects which have six legs, all arachnids have eight legs. Emperor scorpions are a shiny jet black color, sometimes having a brown or green tinge in certain lighting conditions, and can attain lengths of six inches to over eight inches, with large pincers also referred to as claws. A scorpion's body consists of two main parts: a cephalothorax, also known as the prosoma, and the opisthosoma or abdomen, which consists of the mesosoma and the metasoma. The cephalothorax is covered by a protective carapace; it contains the eyes, chelicerae (mouth parts), specially developed limbs that are formed into pincers called the chelae, and four pairs of legs. The chelae, commonly referred to as pincers or claws is comprised of an immobile manus or tibia and a moveable “finger” called the tarsus used to pinch prey items and predators alike. The mesosoma consists of seven body segments, covered by chitinous plates known as tergites, which contain the reproductive organs and the book lungs. Although the metasoma is sometimes referred to as a tail, it is actually considered an extension of the abdomen and is made up of five caudal segments which contain part of the intestines and the hindgut. The metasoma is connected to a telson which consists of the venom sacs and the stinger or aculeus.
As with other invertebrates, scorpions will need to shed their exoskeletons in a process known as molting in order to grow. Emperor scorpions will typically molt six to seven times in about fourteen to twenty-two months before reaching maturity, research suggests that they may no longer need to molt once they have reached maturity.
All scorpions are known to fluoresce or glow when exposed to certain wavelengths of ultraviolet light such as those produced by a black light.
Emperor scorpions are found in tropical areas of western Africa in several countries including Togo, Ghana, Nigeria, Benin, Congo, Senegal, Guinea, Sierra Leone, and the Ivory Coast. They are mainly nocturnal predators found in humid forests but are sometimes active during the day and crepuscular hours under low light conditions. They can be found living in shallow underground burrows, underneath ground cover, inside hollows within rotting logs, under and within tree roots, or foraging for prey amidst leaf and other ground litter. They have been found dwelling in colonies consisting of dozens of individuals in areas where prey is plentiful.
Generally emperor scorpions greater than 3 inches in length mainly rely on the crushing power of their pincers to subdue prey and to deter predators rather than their venomous sting. It has been reported that sub-adult and adult males are more prone to a stinging defense than larger, typically more docile females.
Emperor scorpions have a lifespan of about six to eight years. They can be kept in a variety of appropriately sized enclosures from plastic sweater boxes to glass tanks, a single adult can be comfortably housed in a space about the size of a 10 gallon tank. They should be kept at a high level of humidity, typically 75 to 85 percent with temperatures ranging from 78 to 85 degrees Fahrenheit, and even up to a 90 degree hot spot. They may be kept communally as long as there is enough space and plenty of hiding places provided although there is always the risk of opportunistic cannibalism of smaller or freshly molted individuals. Emperor scorpions will require three to six inches of substrate in order to allow them to burrow. Substrates such as peat moss, potting soil, cypress mulch, and coconut fiber (commonly sold as Eco Earth) or a mixture of different substrates are all appropriate choices. If using heat pads or under tank heaters, they should not be mounted underneath enclosures because the heat will not be able to penetrate through a thick layer of substrate. Some keepers employ a false bottom method in order to maintain high levels of humidity, especially if the enclosure is heated by means of a lamp with either a heat emitter or a basking bulb, by filling the bottom layer of the enclosure with gravel and keeping the gravel level half filled with water at all times by pouring water through a tube that reaches under the substrate to the gravel layer. In order to provide a proper environment they will also need to be provided with hides which can be created with a variety of materials from cork bark flats and rounds, ceramic flower pots, and even commercial hides commonly advertised for reptiles. Cork bark flats also provide males with a place to deposit their spermatophores during mating.
Emperor scorpions can be fed a wide variety of invertebrate prey such as crickets, roaches, superworms, and they may even be occasionally offered pinky or fuzzy mice, but offering vertebrate prey is not strictly necessary. Water should be provided via a wide, shallow dish and also by misting the enclosure which can also help maintain adequate humidity levels.
Emperor scorpions are sexually dimorphic with males being smaller and slimmer than females. Gender can also be determined by examining the pectines, the structures on the ventral side of their bodies that resemble combs with bristles known as setae. The pectines of males have longer setae than females and males also have a greater amount of granulation on their pincers.
During mating, the male and female will begin their courtship by locking pincers in a “dance”. While they are locked together the male will seek a suitable spot to place his spermatophore and then maneuver the female over it where she will force the spermatophore into her genital operculum thereby releasing the sperm into her reproductive tract.
It is recommended that if scorpions are being kept in communal groups, pregnant females or females with young should be removed to a separate enclosure to reduce stress and prevent possible cannibalism of the young by other individuals or even by a stressed mother. Some mother scorpions may still cannibalize their own young due to stress or other unknown factors. The gestation period of emperor scorpions ranges from seven to ten months which produces anywhere from fifteen to thirty live young (true scorpions do not lay eggs unlike some related species) which are carried on the mother's back. Prior to the first molt, known as the post-embryonic or first instar stage, the scorplings have not fully developed, bear little resemblance to adults, and are even unable to eat relying on internally stored nutrients. They are highly susceptible to desiccation especially if removed from the mother, it is hypothesized that they are dependent on the mother scorpion to provide a sufficient moisture gradient. After fourteen to eighteen days, the first instars will have finished embyronic development and molt into fully functional, miniature versions of adults.
The mother scorpion will kill prey items which the scorplings will descend from her back to feed upon. Within a month or two the scorplings will be completely self sufficient and no longer need to carried on their mother's back. In order to successfully thrive and molt without issues, emperor scorplings will need to be kept in very humid conditions that approach 100% humidity with high temperatures in the 90 degree Fahrenheit range until they reach fourth instar when they can be kept in the same conditions as adult specimens.
In recent years the availability of emperor scorpions for sale in the captive market has decreased in part due to the suspension of trade from the countries of Benin and Togo on May 3, 2013 imposed by CITES. To date, emperor scorpions are still able to be exported from Ghana but captive breeding efforts are necessary to ensure that future generations will still be able to enjoy keeping these interesting creatures.