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The spider family Sparassidae (giant crab spiders or huntsman spiders) includes 1148 described species (Platnick 2014). Sparassidae includes the spiders with the largest leg-span (Heteropoda maxima, to 30 cm), a worldwide invasive (Heteropoda ventatoria), and the star of the major Hollywood movie Arachnophobia (Delena cancerides) (Agnarsson and Rayor 2013).
Reviewing then current knowledge of North American sparassids in 2005, Lew reported that nine species were known from North America north of Mexico. Of these nine North American sparassids, Olios included seven described native species in the western United States (and likely a number of undescribed species as well); the non-native Psudosparianthis cubana was known from Florida (Fox 1937 cited in Lew 2005); and the non-native pantropical Heteropoda venatoria, was reported to have established populations in Florida (this is the largest spider commonly found indoors in Florida, with a leg span up to 10 cm) and occasionally to be found synanthropically in other southern states and in California. (Lew 2005) However, Rheims (2010a) revised the Nearctic (North America plus northern Mexico) sparassid fauna and concluded that in fact there are only four valid Olios species in this region, not seven, plus the former Olios mohavensis, which has been transferred to Macrinus (Rheims 2010b). Rheims concluded that the remaining Nearctic species currently included in Olios should be placed in new genera as well, but that these changes could be made until a more thorough revision of the Nearctic and Neotropical fauna, especially that of Mexico and Central America, has been undertaken.Although there have been few other regional reviosions of the Sparassidae, Agnarsson and Rayor (2013) undertook a phylogenetic analysis of a large endemic lineage of Australian sparassids, the Deleninae.
The family Sparassidae has also been known as Heteropodidae (a junior synonym), as well as Eusparassidae (the latter mainly by authors who consider Sparassus to be a junior synonym of Eusparassus). (Lew 2005 and references therein
Sparassids are cursorial and ambush predators and excellent climbers (easily clinging to ceilings in buildings). Their flattened bodies and laterigrade legs (i.e., legs that extend sidewise with the femora, especially, twisted so that the front surface faces up) allow them to fit into surprisingly small crevices given their often large bodies and long legs. They typically have eight eyes arranged in two rows (but see Jaeger 2012). (Lew 2005 and references therein).
Henschel (2002) reported on the navigational abilities and mating system of Leucorchestris arenicola. Nørgaard et al. (2007, 2008, and 2012) have found that spiders of this species orient back to their burrows by learned local visual cues.
Delena cancerides exhibits social behavior (remarkable among known social spiders in that it does not spin a web) that has been the focus of a number of investigations (Rowell and Avilés 1995; Beavis et al. 2007; Yip et al. 2009; Yip and Rayor 2011; Auletta and Rayor 2011).
Lake (1986) reported a possible example of parthenogenesis in a sparassid, Isopoda insignis.
A study of bites by sparassid spiders in Australia found that their bites cause relatively minor symptoms in humans. Bites appear to be characterised by immediate and transient pain, associated with bleeding, puncture marks and local redness. The mechanism of effects appeared to be trauma rather than due to any venom. (Isbister and and Hirst 2003).
(Lew 2005; Btadley 2013)