|Tarantula (Aphonopelma spp)|
DESCRIPTION: Length up to 3-4" (75-100mm). The species most commonly found here have females that are overall tan and males that are dark brown to black and thinner-bodied than the females. Both males and females have stout, hairy legs and a hairy abdomen. Mature males have hooks on their front legs (see in upper picture).
NATURAL HISTORY: Venomous, but only mildly toxic to humans, and they usually do not bite humans unless handled roughly. Urticating hairs on abdomen may be brushed off by the spider and can cause severe irritation when they contact sensitive tissues (e.g., eyes). Tarantulas are nocturnal and stay very close to their burrows. Tarantulas excavate their own burrows, which often extend about a foot underground. Their burrows are lined with silk, and silk threads radiate from the entrance to detect passing prey (usually other arthropods) or males interested in mating. Tarantulas take about 10 years to mature, at which time males leave their burrow and wander around looking for females (thus, most tarantulas you see will be males looking for mates). The mating process is hazardous because the male has to position himself under the female and uses his pedipalps (those shorter, leglike appendages in front of the spider's fangs) to inseminate the female. To protect against the female's natural tendency to eat any arthropod that is beneath her, the mature male uses the hooks on his front legs to hold the female's fangs out of the way so that she can't use them against him during mating. After mating, the male runs for his life (sometimes he doesn't make it in time). Males will mate with as many females as possible, but at the end of the season, the males die. The females, however, can live up to 20 or more years, but must mate again each year. Fed upon by Tarantula Hawk larvae.