Olios giganteus

Summary

The "Giant Crab Spider," Olios giganteus, lives up to its name. Females have a body length of 15-48 millimeters, and a leg span up to 64 mm (2.5 inches). The species ranges from southern California to Nevada, Utah, Arizona, New Mexico, and extreme west Texas. Their typical habitat is arid lands in the Sonoran Desert and similar ecosystems. They are nocturnal, prowling vertical surfaces: shrubs, trees and the exterior walls of buildings. They do not spin a web to catch prey, but easily overpower most insects. By day, the spider hides in cracks, crevices, beneath loose bark on trees, and similar snug situations. Mature specimens may be found throughout the year, but especially in summer. The female spins an egg sac inside a large, spherical retreat where she resides, guarding the sac and the spiderlings that emerge after about one month, in mid- to late summer. This spider occasionally strays indoors, a habit that decades ago inspired newspaper stories of the “barking spider” in small towns in west Texas.