Scorpions - introduction

by Todd Gearheart

Welcome to the Scorpion-keeping hobby!

Since the early 1990's, the scorpion hobby has really taken off and developed well. It is second to the tarantula-keeping hobby amongst invertebrate keepers. Scorpions are fascinating and bizarre-looking creatures. They have a totally unique appearance and their behaviors are very amazing to watch. They are easy to keep, cost us pennies a month to feed per month and take up little room. They are perfect "display animals" for busy people and can be housed in shoe boxes or small glass or plastic tanks. They are a great "conversation" animal to have displayed in a den or living room. The EMPEROR SCORPION (Pandinus imperator) is the most popular species due to its size, docile nature, price and hardiness. Over 50 species have been made available on a regular basis for scorpion enthusiasts. The internet is full of web sites with picture and information about scorpions and the hobby. We encourage you to catch the fever and keep these neat animals to enjoy watching and observing their fascinating behaviors and interesting appearances.

Natural History: Scorpions live in a variety of habitats, but prefer warm climates. Many people believe scorpions only live in deserts, but there are many species in rainforest habitats along with montane species in high altitude mountain habitats. There are small scorpions under 1.5 inches in length, while others, such as Hetermetrus swammersdami, have been recorded over 9 inches! The largest fossil scorpion was Praearcturus gigas, which was three feet in length! Scorpions have been around for an estimated 350 million years. They have evolved very little making them some of the most primitive animals on earth.

Commerical History: Scorpions were usually only kept by scientists for study until the 1980's, when species like the EMPEROR SCORPION Pandinus imperator was imported by reptile dealers and kept as "pets". The 1990's was the decade where scorpions picked up in popularity and more species were made available in the hobby. Today, over 50 species are imported, bred and/or made available on a regular basis. The hobby has advanced now to the point of keepers requesting sexed species and even color morphs of different locales, and there are advanced keepers, like myself, and dealers, that provide such service and large variety of species.

Anatomy: Scorpions are covered by a thin, hard, exoskeleton that protects and supports the internal organs. Their bodies are divided into two parts: the prosoma (cephalothorax) and the opisthosoma (abdomen). On top (dorsally), the prosoma is covered with the carapace. Their chelicerae are mouthparts which enable the scorpion to tear and grind food. They have median and lateral eyes located on the carapace. Four pairs of jointed legs on the cephalothorax provide locomotion and are used for digging. Pedipalps (six segmented appendage in which the last two segments are the "claws") are used for grabbing, holding, crushing prey, digging, protection, and they can carry sensory organs. Scorpions have poor eye sight, but make up for it with sensory organs such as having setae on their bodies to pick up and evaluate scents, air movements and vibrations. Setae are hairlike projections used to sense air movement and vibrations. Some scorpions can stridulate by rubbing one part of their body against other. This sounds like a "hiss". The Opistophthalmus genus of Southeastern African are very audible with their stridulation. Pectines is a pair of comb-like appendages underneath scorpions near their tails that pick up ground vibrations and are used to sense pheromones in mating. The "fingers" protruding off this structure provide the hobbyist an opportunity to accurately sex a scorpion as males tend to have wider pectines and longer "fingers". The "telson" is the round ball structure at the end of the tail where the stinger protrudes from.

Taxonomy: This is the science of classifying living things. There are very few scorpion taxonomists actively working today. There are only a few dealers that can identify scorpions to genus level, let alone species level. A mistake that many keepers make is trying to identify scorpions based on color and/or patterns alone. Proper and correct identifications are made based on physical and molecular characteristics. There are over 1,500 described species of scorpions and sixteen families (listed below):

  • Bothriuridae
  • Buthidae
  • Chactidae
  • Diplocentridae
  • Euscropiidae
  • Heteroscorpionidae
  • Ischnuridae
  • Iuridae
  • Microcharmidae
  • Pseudochactidae
  • Scorpionidae
  • Scorpiopidae
  • Superstitionidae
  • Troglotayosicidae
  • Vaejovidae

Keeping as Pets: Scorpions should not be thought of as traditional "pets" such as cats and dogs. Along with many invertebrates and reptiles, they should be treated as "display animals". There are several reasons for this. First, scorpions are very primitive and do not possess much intelligence the capability of displaying emotions. There is no such thing as a "tame" or "mean" scorpion. There are placid species reluctant to sting and there are nervous, high aggressive species that sting readily. Secondly, many scorpions are very active and nervous and do not like to be handled. Lastly, there are about 24 dangerous scorpions with medically significant venom. Scorpions should not be kept by children under 18 years old (unless they are non-dangerous species being kept by a mature-minded and responsible child that is closely supervised by a responsible parent) and anyone that has mental problems that would make the safe-keeping of scorpions impossible. A general rule of thumb is if the scorpion has a fat tail with narrow claws, it is most likely aggressive and highly venomous. Species that possess these physical characteristics should not be kept by minors or beginners.

Beginner species: The following species are recommended for beginners:

  • EMPEROR SCORPION Pandinus imperator = a large, black, rainforest species from equatorial Africa that is fairly placid and docile.
  • FLAT ROCK SCORPION Hadogenes troglodytes = a large, brownish to black species with large claws and skinny tail that lives in a savanna/rock habitat.

Intermediate species: These scorpions are faster and aggressive than the list above and some have a more toxic venom.

  • FLORIDA BARK SCORPION Centruroides gracilis = medium-sized, dark brown scorpion found on Florida's barrier islands and in coastal habitats. Hardy, but is aggressive.
  • DESERT HAIRY SCORPION Hadrurus arizonenesis = somewhat large scorp (to 6.5"), desert yellow in color from scrub/desert habitats. Very hardy, but aggressive.
  • ASIAN FOREST SCORPION Heterometrus spinifer = large, black rainforest from SE Asia. Hardy, but aggressive.-CA BLACK-TIPPED Anuroctnus phaiodactylus = med.-sized, forest/scrub species in desert yellow with black-tipped claws.
  • Scorpions of the following genera: Anuroctnus, Babycurus, Diplocentrus, Grosphus, Hadruroides, Hetermetrus, Hadrurus, Lychas, Nebo, Iomacus, Opisthacanthus, Opistophthalmus, Scorpio, Uroplectus, Isometrus, Euscorpius, Brachistosternus, Bothriurus, Uroctonus, Smeringurus, Vaejovis, and some Centruroides (C. gracilis and C. hentzi), but beware of geographical morphs of C. gracilis from Central America and any Mexican, Central American Centruroides spp. as these species are highly venomous. Also, C. excilicauda from Arizonia and Mexico is dangerous.

Advanced species: These species are more delicate to keep and/or highly venomous and should not be kept by minors and intermediate hobbyists. These species are mainly for professionals to keep.

The following genera (and specific species are medically significant (dangerous!):

Androctonus, Apistobuthus, Buthus, Buthacus, Centruroides spp. from Mexico, Central and South America along with C. exilicauda from Arizonia and Mexico, Hottentotta, Leiurus, Mesobuthus, Parabuthus, and Tytius spp.

Housing:

Desert/scrub species: well-ventilated, plastic shoe box to 5 gallon tank filled with 3"-5" sand, provide cork bark or rock shelter and milk cap for water dish. Temp: 78F-85F Humidity: 0%-20%.
Savanna species:
Same as above, but use sand/peat moss mix and provide slighly larger water dish and slate rocks for shelter. Temperature: 78F-85F Humidity: 20%-40%.
Rainforest species:
Same as above, but use slightly moist peat moss, cork bark shelters and larger water dish. Temperature: 78F-85F Humidity: 80%.
Montane, rainforest species:
Same as above, but maintain cooler temps of 65F-78F.

Water: See above "Housing" section depending on what habitat your scorpion species comes from. From personal experience, I never gave North African or Middle Eastern species any water or humidity. That get that from their insect prey.

Feeding: Feed desert/scrub and savanna species 1-2 times a week 1-3 crickets, super worms, meal worms or roaches. Feed rainforest and montane species more frequently. Large scorpions (ones that achieve lengths over 5") can kill and eat pinkie/fuzzy mice and small reptiles (like Anolis lizards).

Handling/transferring: I do not recommend handling any scorpion with your bare hands. Pandinus and Hadogenes spp. are fairly docile and placid and can sometimes be allowed to crawl onto a flat hand (depending on the individual animal's reaction), but I still do not recommend free-handling or picking up a scorpion. I've witnessed too many stings, even from Pandinus imperator. For transferring your scorpion I recommend the following tools and techniques:

  1. Work in a clear, well-lit work area.
  2. Work "tank-within-a-tank" (Use a large plastic or glass tank to work "in" tranferring the scorpion over and within the larger tank). This will give you an extra barrier area in case the scorpion escapes or wiggles off the thumb tweezers.
  3. Use 10"-16" thumb tweezers with rubber-padded tips to gently pick up your scorpion at the end of their tail for quick transferring.

*** NEVER FREE-HANDLE A DANGEROUS SCORPION!!! I shouldn't have to write this, but there are some idiots that have done this out there. It is not worth risking your life over.

Sexing: Generally, male scorpions are smaller and less stocky as females, males of the genera Centruroides and Hadogenes have longer, slimmer tails, many have more "granulation" on their claws and their pectines are wider with more "fingers/teeth" that also appear longer. Females have shorter-angled pectines with a smaller number and shorter length of "fingers/teeth". Females are generally larger in length and much bulkier thans males too.

Breeding scorpions/Raising up babies: For captive breeding success, I recommend the following techniques and information:

  1. Make sure you have "mature" scorpions of the opposite sex to breed.
  2. Use a large tank (10-20 gallon) and provide multiple shelters.
  3. Keep both scorpions well-fed, especially the female.
  4. For desert/scrub and savanna habitat species, you will need to simulate the "rainy season" by misting the tank substrate a few times a week.

Gestation period can be two months to 18 months (desert/scrub species take the longest time.) Small, white embryos are laid and crawl onto the females back. When you see this remove the male. When the babies come off the mother's back and start to darken up, remove the female from the tank. After molting out, feed the babies prey items that are similar to the size of their bodies (usually pin-head and small crickets and for small species, termites, wingless fruit flies and mini-meal worms.)

Health issues (parasites, molting, injuries): To cut down or eliminate mites from taking over your scorpion's tank and killing your scorpion, get into the habit of feeding your scorpion at night and removing the leftover remains (if any) the following morning. Keep water dishes clean and clear of discarded or uneaten prey items. For rainforest species especially, make sure the tank has adequate humidity (80%) for molting. If using rocks in your tank, make sure they are secure or heavy enough that the scorpion can not make the rock loose and get injured from it. Buy captive-born scorpions over wild-caught ones whenever available. Right now, the scorpion trade is dominated by wild-caught imports, so buying captive-born species isn't always possible. With this dilema, only buy wild-caught scorpions that have been well-acclimated and have fed at least once since being caught or imported.

Interesting trivia:

  • Many scorpions will "glow" under a black light.
  • The world's largest scorpions are of the Hetermetrus, Pandinus and Hadogenese spp. with H. swammerdami holding the record at over 9.7 inches!
  • Scorpiops rohtangensis has been found at 14,000 in the Himalayas of Asia and Orobothriurus altola lives at 14,400 feet in the Andes of South America.
  • In venom composition, the DEATH STALKER Leiurus quinquestriatus is the most venomous scorpion of the world.
  • The species attributed to the most deaths in the world (due to its potent venom and wide spread range) is the YELLOW DESERT SCORPION Androctonus australis.
  • Roughly 2,000 people die from dangerous scorpion's stings every year. Most of these stings happen in Latin America, Northern Africa, the Middle East and India where several dangerous species live and the people living there often do not have shoes and/or good medical care with anti-venom made available for them.
  • Over 200,000 EMPEROR SCORPIONS (Pandinus imperator) are imported every year out of West Africa for the American pet trade.

Recommended publications, links and societies:

Brownwell, P.H., and G.A. Polis, eds. Scorpion Biology and Research. Oxford, England: Oxford University Press, 1999.
Fet, V., W. D. Sissom, G. Lowe, and M. Braunwalder. Catalog of the Scorpions of the World (1758-1997). New York, NY: New York Entomological Society, 1999.
Jackman, J.A. A Field Guide to the Spiders and Scorpions of Texas. Houston, TX: Texas Monthy Press, 1997.
Keegan, H.L. Scorpions of Medical Importance. Jackson, MS: University of Mississippi, 1980.
Levi, H. W., and L.R. Levi. Spiders and Their Kin (A Golden Guide). New York, NY: Golden Press, 1990.
Marshall, S. D. Tarantulas and Other Arachnids. Hauppauge, NY: Barron's Educational Series, Inc., 1996.
Polis, G., ed. Biology of Scorpions. Palo Alto, CA: Standord University Press, 1990.
Pringle, L. Scorpion Man: Exploring the World of Scorpions. New York, NY: Charles Scribner's Sons, 1994.
Rubio, M. Scorpions - A Complete Pet Owner's Manual. Hauppauge, NY: Barron's Educational Series, Inc. 2000.

Links:

Arachnology Home Page: www.dns.ufsia.be/arachnology/arachnology.html
Emperor Scorpion Home Page: www.slip.ne/~drrod/
Scorpion Enthusiasts Forum: www.wrbu.si.edu/www/stockwell/
Hadrurus Page: www.fortunecity.com/tinpan/morrissey/432/hadrurus
Singapore Scorpion Page: www.sunflower.singnet.com.sg/~caijw/welcome.html

Societies:

American Arachnological Society, c/o Dr. Norman Platnic, AMNH, Central Park West at 79th Street, New York, NY 10024
British Arachnological Society, c/o S. H. Hexter, 71 Havant Road, Walthamstow, Londo, E17 3JE England
British Tarantula Society, c/o Ann Webb, 81 Philimore Place, Radlett, Hertfordshire WD7 8NJ England
Young Entomologist's Society, 1915 Peggy Place, Lansing, MI 48910-2553

Resources used for this page:

Polis, G., ed. Biology of Scorpions. Palo Alto, CA: Standord University Press, 1990.
Rubio, M. Scorpions - A Complete Pet Owner's Manual. Hauppauge, NY: Barron's Educational Series, Inc. 2000.