That Reptile Blog – Reptile, Amphibian and Exotic Pet Care and Information

Approximately 2,000 scorpion species have been described, but most arachnologists believe that many more await discovery.  Few, however, expected an unknown species to turn up within sight of a major city in the USA.  But that is what happened earlier this year, and the discovery was unusual for other reasons as well.  Another noteworthy new scorpion species surfaced in the Ecuadorean Andes, a little-studied region long suspected of being a diversity hotspot for scorpions.  New Arachnids of all kinds are regularly discovered…please post our own news items and thoughts at the end of this article.

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A Unique Scorpion from Arizona’s “Sky Islands”

One never knows where new invertebrates will appear.  In 2000, a new centipede was found in NYC’s Central Park, of all places.  Still, the discovery of a sizable scorpion now known as Vaejovis brysoni was surprising on several levels.  The scorpion was discovered accidentally, in an area of the Santa Catalina Mountains that had been well-studied (6 new species have been found there since 2006), and within sight of Arizona’s capitol city of Tuscan (please see photo).

Also very surprising is the fact that the new scorpion’s habitat is considered by biologists to be a “sky island”.  Sky islands are mountain tops that have become isolated from nearby mountains that contain similar habitats and species.  The valleys between the mountain tops prevent scorpions and other animals from breeding with one another.  Over time, these isolated populations evolve into distinct species.  Oddly, another scorpion of the same genus is already resident on V. brysoni’s “sky island”.  This is the first time that closely related animals have been found on the same mountain in this region.  Learning how 2 similar species survive in close proximity to one another should provide interesting insights into scorpion evolution. Read More »

I can’t remember a time when scorpions did not fascinate me, and their lure grows stronger with each new species I encounter.  In the past, I’ve written on the care and natural history of Emperor, Flat Rock, Asian Forest and other popular scorpions.  Today I’d like to present a general overview.  I hope it will help you to decide if a scorpion is the right choice for you and if so, how to get started.

What’s in Store for Scorpion Fans

Among the world’s 2,000+ scorpion species we find an astonishing diversity of fascinating creatures, many of which make hardy pets that adjust well to small enclosures.  Several reproduce readily in captivity – lucky scorpion keepers may even be treated to the sight of a female feeding her offspring with crickets!  At least 15 species are established in the pet trade, and specialists are working with several others. Read More »

As is true for tarantulas, reptile enthusiasts (myself included) are often interested in scorpions.  Today I would like to provide an overview of these most ancient of animals (they were likely the first creatures to leave the sea for a terrestrial existence), with specifics concerning some readily available species to follow next time.

Please Note:  All scorpions manufacture venom and are capable of delivering a painful sting. Human fatalities are rare but not unknown, and the venoms of many are relatively unstudied.  Also, an allergic reaction is always possible…during my years at the Bronx Zoo I was often in contact with scorpion researchers….some reported relatively severe reactions from species not known to be dangerously venomous.

Unfortunately, the trade in scorpions is not well-regulated, and highly venomous species do appear from time to time (I’ll relate a personal experience in Part II of this article).  Purchase scorpions only from reliable sources, and be sure you can identify the species you are considering.  That being said, some of those best-suited to captivity are not dangerous, and make fascinating terrarium subjects.  Please check the legalities of scorpion ownership before acquiring one, as such is regulated in some areas.

Do not grab scorpions by hand, despite what you may see others do.  To move a scorpion, use a long handled stainless steel hemostat to gently grasp the telson (“tail”).  A bit of foam rubber should be secured to the tips to prevent the scorpion from being injured. 

Classification

Scorpions are classified in the order Scorpionidae, and, along with spiders, ticks and mites, in the Class Arachnida.  Nearly 2,000 species have been described (as opposed to 40,000+ spiders), ranging in size from .3 to 8.5 inches in length.  The 4 inch long Cetrruroides gracilis is the largest species in the USA, while the South African flat rock scorpion (Hadogenes troglodytes) is the world’s longest and heaviest.

Range and Habitat

Scorpions are found in tropical, sub-tropical and (less commonly) temperate regions of all continents except Antarctica, and are absent from New Zealand.  Various species are adapted to live in deserts, open forests, grasslands, caves and rainforests.  Some are quite at home around people, and may be found in overgrown fields, agricultural areas, gardens, parks and even within homes.

A surprising number thrive in quite cold climates, ranging as far north as Canada and southern Illinois in North America.  A feral colony of a small African species, introduced in produce shipments, is established in southern England.  In the USA, scorpions reach their greatest diversity in the southwest, where 60+ species may be found.

Diet

All are predacious, with most consuming soft-bodied insects but some specializing in land snails, sowbugs and other scorpions.  Larger species may take frogs, lizards, shrews and other sizable animals on occasion.

Reproduction

All scorpions thus far studied give birth to live young, and a number are parthenogenic.  Females typically carry the soft, relatively defenseless young on their backs for a time.  Many species feed their offspring with shredded insects…in some the young are totally dependant upon their mothers for food and will perish if separated too quickly.

In contrast to most of their spider relatives, certain species, including the popularly kept emperor scorpion, are quite social and may be housed in colonies.

Venom

Scorpion venoms are not well-studied, but thought to be quite complex.  Some that have been analyzed have yielded compounds with potential medicinal value.  Most seem to be neurotoxic in nature, but cytotoxic varieties are known as well.

The larger scorpion species are generally not dangerous to people, while some of the very small ones have caused fatalities.  Most of the 25-30 species thought to be capable of delivering serious stings are classified within the Genera Centruroides, Androctonus and Tityus.  However, as we have limited knowledge of scorpions in general, all should be treated with caution.  As mentioned, the possibility of allergic reactions to even weak venoms is always a possibility.  In all cases, small, straw-colored scorpions from the Middle East and North Africa should be avoided.

Scorpions in Captivity

At least 15 species are well-established in captive breeding populations, and many others are regularly available.  Fortunately, one of the largest and most interesting, the emperor scorpion, is also quite benign.  It lives well in groups, and females are surprisingly attentive to their young.  Next time I’ll write about the care of this and other popular species.

A short introduction to scorpion ecology, along with a diagram of their body parts and photos of common species of the American Southwest, is posted at:

http://wc.pima.edu/~bfiero/tucsonecology/animals/arth_scorpions.htm