Desert tarantulas known specifically as Aphonopelma chalcodes, live in the southwestern region of the United states. Popular states include Arizona, New Mexico and Nevada. Regions expand into parts of California and Mexico.
Aphonopelma chalcodes live under the ground by either burrowing under the soil or taking over abandoned homes left by various rodents. Once a chalcodes selects its habitat, it may reside in the same place for decades. The desert climate requires that the chalcodes adapts to harsh conditions. It can live on very little water and adapts well to extreme heats during the day and frigid temperatures at night.
While sexual dimorphism is evident in adult chalcodes, this is rare as most other species are not identifiable. Males have a diameter of 49 to 61 mm, whereas females range from 49 to 68 mm, with a leg span of approximately 98 mm. Like other similar species chalcodes or desert tarantulas are covered with fine hairs throughout their body. Like all spiders, tarantulas are divided into two segments or body sections: the cepholothorax and the abdomen.
When young tarantulas emerge from the egg it is almost impossible to identify the sex. All chalcodes resemble female at birth. It is not until later that sexual differentiation occurs. Most spiders do not live long enough to reach sexual maturity as they are either eaten by prey or starve to death.