By Dirk Stevenson
A search for imperiled snakes led to the discovery of a rare – for Georgia – and remarkable arthropod.
In December, Matt Moore and Ben Stegenga of The Orianne Society were doing a DNR-supported survey for federally threatened eastern indigo snakes at Little Ocmulgee State Park near McRae when they saw a fresh snake track at a large gopher tortoise burrow. Using a burrow camera, they scoped the tunnel to find a good-sized eastern diamond-backed rattlesnake curled about 6 feet from the entrance.
The men watched the rattler, chuckling as it tongue-flicked the cylinder that houses the camera, before getting ready to go. Then they noticed an odd-looking arthropod scurrying between their legs in the burrow’s sugar-sand apron.
It was a wind scorpion, and apparently the first recorded for the state.
Wind scorpions are arachnids yet they are neither true scorpions nor spiders. They are members of the order Solifugae, derived from Latin for “those who flee from the sun” and referring to the invertebrates’ nocturnal habits. Wind scorpions are also commonly called camel spiders, sun spiders and solifuges.
Most wind scorpion species are solely nocturnal and rarely collected. Many are known only from the type specimen. Worldwide, there are about 1,100 species. Although one is known from the damp Monteverde Cloud forest region of Costa Rica, where UGA oversees a field station devoted to cloud forest research and education, most species occur in dry, arid climates in grassland and desert habitats.
Arid portions of the Middle East, Africa and western North America are rich in wind scorpions: Nearly 200 species are known from mainland western North America. The southwestern U.S. and adjacent Mexico, especially the Sonoran and Chihuahuan desert regions, support diverse wind scorpion faunas. Yet only one species is known from east of the Mississippi River. Ammotrechella stimpsoni has been documented only in peninsular Florida and the West Indies.
Wind scorpions are both beautiful and fearsome in appearance. Many species are a luscious blonde-yellow in ground color. But their mouthparts will give you pause. Wind scorpions come armed with the largest jaws (chelicerae) for their body size of any invertebrate. Two large chelicerae adorned with bristly spines and sensory hairs give wind scorpions a wart-hoggish look. These chelicerae are powerful crab-like pincers capable of cutting through the exoskeletons of their arthropod prey.
Wind scorpions have four pairs of legs, although it looks as if they have five – the anterior-most pair are actually pedipalps, not true legs. The tips of these elongate, antennae-like sensory organs, held aloft when foraging, end in adhesive structures.
In the preface of The Biology of Camel-Spiders: Arachnida, Solifugae, author and arachnid expert Dr. Fred Punzo relates a west Texas encounter with a wind scorpion that stimulated his interest in the group. To paraphrase, Punzo writes that on a warm night in 1986 in the desert wilds of Big Bend National Park, he placed a cricket near the entrance of a tarantula burrow, hoping to photograph a resident female tarantula capturing prey.
Suddenly, phantom-like, the yellow form of a large wind scorpion materialized, nabbed the bait and hauled it under a nearby mesquite.
Startled, Punzo regrouped, then tried to collect the wind scorpion. When confronted by Punzo’s forceps the wind scorpion dropped the cricket, lunged and grabbed the forceps tightly in its jaws!
Legends and myths about wind scorpions abound. Many exaggerate these invertebrates’ size and the danger they pose to humans. (By the way, don’t believe everything you read on the Internet. Wind scorpions do not eat human flesh, disembowel camels or leap high in the air.) Notably, these arachnids lack venom glands and cannot deliver venomous bites or stings. The larger species of wind scorpions are capable of giving humans a painful nip, via their enormous chelicerae, but not inflicting serious injury.
The largest wind scorpions, though impressive by invertebrate standards, reach about 3-4 inches in body length and 5-6 inches with legs fully extended. Adults of most species, however, are about an inch long. Wind scorpions are named for their ability to move rapidly, up to 10 mph for short distances.
There are many colorful local names for these bizarre arachnids, including scorpion carrier, bulldozer spiders (heard in west Texas) and sand puppies (in Wyoming). In Africa one might here the term beard-cutter (“baarskeerder,” from the Afrikaans) in reference to the erroneous belief that wind scorpions use their formidable jaws to clip human hair to line their nests.
A week after the discovery of the wind scorpion at Little Ocmulgee State Park, Moore and I returned to the site with hopes of finding additional specimens. We looked beneath the exfoliating bark of giant pine snags and scratched about in the sand of gopher turtle aprons and sand dunes, but the strange little critters eluded us. We did enjoy a lengthy hike through park habitats that harbor a lineup of creepy crawlers— bark scorpions, assassin bugs, trapdoor spiders, black widows and coral snakes, in addition to diamondback rattlers and wind scorpions.
Could the singularly odd Mastigoproctus giganteus (giant whip scorpion) – a 4-inch-long, ebony-colored burrowing invertebrate that resembles a lobster – also turn up someday in south Georgia? Like the wind scorpion, this western group has a species that over geological time colonized Florida.
It’s likely that the wind scorpion that Moore and Stegenga observed is the same species, Ammotrechella stimpsoni, known from a variety of habitats in peninsular Florida. But it’s also possible this could be an as-of-yet undescribed species. Ammotrechella stimpsoni is a fairly small (adults are from about ½- to just less than 1-inch long) and secretive species, apt to go unnoticed except by observant naturalists (note: mole crickets are sometimes misidentified as wind scorpions). Specimens have been found under bark, in termite tunnels and in rotten wood, and on structures at night, indicating that foraging individuals may sometimes climb. They are also capable of making burrows in the sand.
Moore, Stegenga and I are planning additional surveys this year at Little Ocmulgee and other nearby state lands. Any wind scorpion specimens we find will be saved for later identification by experts. But, if you have photographed a wind scorpion in Georgia please let us know.
Well-known Georgia naturalist Dirk Stevenson is a herpetologist and Longleaf Savannas Initiative director with The Orianne Society. He blogs at The Naturalist and can be reached at firstname.lastname@example.org.