So-called sun or wind spiders (wind because they can move very fast) are often large arachnids that hide away in burrows, under stones and in cracks and crevices, mainly in arid and semi-arid areas of the world. Of all living animals, these probably have the largest jaws in relation to their body size. Their chelicerae are huge, often exceeding the length of the prosoma. Their pedipalps are leg-like, lacking terminal pincers, but possessing adhesive suckers used in capturing prey. Virtually no prey is too big! Not only are large insects taken, but also small vertebrates including lizards. Like pseudoscorpions, they breathe using tracheae.
Mating is somewhat bizarre, with the male stroking his partner to sooth her to sleep. He then turns her over, secretes a blob of sperm fluid on to the ground, opens her genital aperture with his pedipalps and scoops the seminal fluid in. After this rather undignified mating, he leaps clear for fear of being eaten! Females lay from 50 to 200 eggs in a special brood burrow. Here she stays with the eggs, waiting for them to hatch. On hatching, she takes her youngsters out and cares for them, catching food and feeding them, until they are large enough to fend for themselves.