Sparassidae (formerly Heteropodidae) are a family of spiders known as huntsman spiders because of their speed and mode of hunting. They also are called giant crab spiders because of their size and appearance. Larger species sometimes are referred to as wood spiders, because of their preference for woody places (forest, mine shafts, woodpiles, wooden shacks).
Like practically all spiders apart from the Uloboridae and some Liphistiidae and Holarchaeidae, Sparassidae use venom to immobilise prey and to assist in digestion. They have been known to inflict defensive bites, but are not widely regarded as dangerous to healthy humans. Huntsman spiders are widely considered beneficial because they feed on insect pests such as cockroaches.
There have been reports of members of various genera such as Palystes, Neosparassus (formerly called Olios) and several others, inflicting bites. The effects vary, including local swelling and pain, sometimes with nausea, headache, vomiting, irregular pulse rate, and heart palpitations, indicating some systemic neurological effects, especially when the bites were severe or repeated. However, the formal study of spider bites is fraught with complications, including unpredictable infections, dry bites, shock, and nocebo effects. An investigation into spider bites in Australia, in which Sparassidae figured prominently, did not note any severe or unusual symptoms resulting from confirmed bites from some of the most notorious genera, particularly Neosparassus.
It is not always clear what provokes Sparassidae to bite people, but it is known that female members of this family will aggressively defend their egg sacs and young against perceived threats. The frequency of bites on various body parts suggests that by far the most are accidental or incidental, resulting from inadvertent handling.