STRANGE CREATURES OF THE DESERT

Solpugid (sun spider)
This feisty predator (Eremobates spp.) has the largest jaws relative to its size of any animal in the world. Only about two inches long, the solpugid moves fast—its prey has little chance of escaping. The two tiny black eyes atop its head provide poor vision, so this arthropod navigates mostly by waving a pair of sticky arms, called pedipalps, in front. You're not likely to see the hairy, sand-colored beast because it's shy and often hunts at night; dusk is the best time to spot one. They live a solitary life, coming together only to mate. The male excretes seminal fluid on the ground, then transfers it with his pedipalps to the female, who buries her 50-200 eggs in the ground. She stays with the hatchlings, feeding them, until they're ready to fend for themselves. The solpugid doesn't have venom, but it shouldn't be handled on account of the powerful jaws. It's beneficial to us because it keeps down populations of ticks, mites, and other harmful arthropods.

Vinegaroon (whip scorpion)
The sharp claws and curved tail of this dark-brown to black arthropod (Mastigoproctus giganteus) resemble those of a scorpion, but the creature lacks any means to inject venom. Instead, for defense, it can aim its whiplike tail with great accuracy and squirt concentrated acetic acid (vinegar) with a small amount of caprylic acid onto a predator. Caprylic acid enables the acetic acid to pass through the hard outer skin of other arthropods. The vinegaroon comes in about 100 species. Three or four pairs of eyes on the sides of its head supplement the two eyes on the front. The slender front pair of legs serve as feelers to navigate and to search out grasshoppers and other prey. Males secrete a sperm sac, which they may transfer to the female. The mother stays with her sac of up to 35 eggs until the offspring hatch, then carries them until they've grown large enough to survive on their own. Vinegaroons are shy and nocturnal, so you'll be lucky to see one. If sprayed, wash or rinse thoroughly with water.

Hercules beetle (rhinoceros or horned beetle)
The Hercules (Dynastes granti) has the largest size—as long as three inches—of Arizona's horned beetles. The male brandishes two splendid black horns, one curving up from his prothorax (section behind the head) and the other downward from his head. The beetle with the biggest horns usually gets the females, though males rarely use the horns to do battle. The beautifully polished head and forewings are gray with brown spots and lines. When threatened, the beetle will squirt a brown substance from its abdomen and fly off with a noisy buzz.

Tarantula
About 30 species of these gentle giants (Aphonopelma spp., Dugesiella spp.) inhabit Arizona's deserts. Adults have a leg span of two to four inches, dense fur on the legs and abdomen, and a light- to dark-brown color. They live in burrows, logs, or under debris, coming out at night to dine on small insects and spiders. Females stay close to home their entire lives—up to 25 years. The males leave their burrows upon reaching sexual maturity at about 10 years, then wander in search of a mate, usually in June through August; this is when you're most likely to see tarantulas. The males die soon after mating; sometimes they're eaten by a female. Females stay with their egg sac for six to seven weeks until the babies hatch; about a week later the youngsters leave their mother's burrow. Both ends of the spider can be hazardous to predators. The tarantula may rear up on its hind legs and bare its fangs, or stand on its front legs and use the other legs to hurl a cloud of hairs off the abdomen; the hairs may be barbed or poisonous. Enemies include some birds, lizards, snakes, and a wasp—the tarantula hawk—which paralyzes the spider and lays eggs to hatch and feed on the body. Bites, rare in humans, should be allowed to bleed for a few minutes, then cleaned. The irritating hairs can be removed with tape.

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