What it means
In Scottsdale, tarantula usually means one particular animal and one particular season. The animal is the Arizona blonde tarantula, a spider with a body three to five inches long and a leg span to match, covered in fine hair. The season is the monsoon. For most of the year tarantulas stay out of sight in burrows, but when the summer rains come, the mature males leave home and walk, crossing roads, trails, driveways and patios in the evening in search of a female.
Locals use the word with a shrug and a warning to the dog. Newcomers use it with a shriek. The desert wildlife field guide puts it plainly: tarantulas wander in late summer and early fall, mostly males looking for mates, and you should leave them be.
The tarantula hawk is the footnote everyone should know: a huge wasp, blue-black with blazing orange wings, that hunts the spiders and carries one of the most painful stings on the continent.
Where you’ll meet it
Desert-edge roads and trails in north Scottsdale, the Preserve, and patios near open desert, mostly at dusk from July into September, often after a storm; the monsoon field manual covers the season. Tarantula hawks work flowering mesquite and milkweed in summer.
Where the word came from
Tarantula is a borrowed name. It began in southern Italy, after the city of Taranto, as the name of a wolf spider whose bite was blamed for a frenzy cured by dancing the tarantella. English later stretched the word to the big hairy spiders of the Americas, which are no relation to the Italian original.
The local species is Aphonopelma chalcodes, called the Arizona blonde or desert blonde for the pale tan coat of the females. Males are darker, with black legs and a reddish abdomen, and they look different because they live differently. A male spends several years in a burrow looking like a female, then matures, leaves for good and spends his last season walking. That is the march locals see each monsoon: the Arizona-Sonora Desert Museum notes that the tarantulas on Arizona roads during the summer rains, July through September, are usually males searching for mates.
Tarantula hawk is a folk name too. The wasps, in the genera Pepsis and Hemipepsis, are not hawks, but they hunt like them, and “tarantula hawk” was a better description than anything the entomologists offered.
What it is not
Not a wolf spider, which is smaller, faster and common in houses. And the tarantula hawk is not a hornet or a honeybee: it is a solitary wasp, so there is no colony and no swarm, only one very well-armed insect minding its business.
The fine print
Blonde tarantulas dig burrows an inch or two wide and line the entrance with silk threads that carry the vibrations of passing insects. Females can live 24 to 30 years without ever moving far; males live roughly 5 to 10 years, most of them in a burrow, before their one wandering season. The venom is weak by spider standards, not much worse than a bee sting for most people.
The tarantula hawk’s life cycle is the stuff of horror films. A female finds a tarantula, stings it into paralysis, and drags the living spider to a burrow, where she lays a single egg on its abdomen. The larva hatches and feeds on the spider for weeks, avoiding the vital organs to keep it alive. Adults, by contrast, drink nectar from milkweed, soapberry and mesquite flowers, and males spend their days perched on tall plants watching for females, a habit called hilltopping. The McDowell Sonoran Conservancy’s insect survey recorded Pepsis thisbe in the Preserve.
The sting is the legend. The entomologist Justin Schmidt, whose insect sting pain index is the standard reference, ranked the tarantula hawk second only to the bullet ant and described it as “blinding, fierce, shockingly electric.” The pain lasts about five minutes and is not medically dangerous unless you are allergic, and the Park Service notes the wasps sting only when provoked. Few predators bother them; roadrunners are one. New Mexico adopted the tarantula hawk as its state insect in 1989 after an election organized by schoolchildren from Edgewood.