Sparassidae is 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. In southern Africa the genus Palystes are known as rain spiders or lizard-eating
spiders. Commonly they are confused with baboon spiders from the Mygalomorphae infraorder,
which are not closely related. More than a thousand Sparassidae species occur
in most warm temperate to tropical regions of the world, including much of Australasia,
Africa, Asia, the Mediterranean Basin, and the Americas.
Several species of huntsman can use an unusual form of locomotion. Carparachne aureoflava
from the Namib desert uses a cartwheeling motion, while Cebrennus rechenbergi uses a
flic-flac motion.
Appearance
Sparassids are eight-eyed spiders. The eyes appear in two largely forward-facing rows
of four on the anterior aspect of the prosoma. Many species grow very large – in Laos,
Heteropoda maxima males attain a legspan of 250–300 mm. Persons unfamiliar with spider
taxonomy commonly confuse large species with tarantulas, but huntsman spiders can generally
be identified by their legs, which, rather than being jointed vertically relative to
the body, are twisted in such a way that in some attitudes the legs extend forward in
a crab-like fashion. On their upper surfaces the main colours of
huntsman spiders are inconspicuous shades of brown or grey, but many species have undersides
more or less aposematically marked in black-and-white, with reddish patches over the mouthparts.
Their legs bear fairly prominent spines, but the rest of their bodies are smoothly furry.
They tend to live under rocks, bark and similar shelters, but human encounters are commonly
in sheds, garages and other infrequently-disturbed places. The banded huntsman is large, grey
to brown with striped bands on its legs. The Badge Huntsman is larger still, brown and
hairy. The tropical or brown huntsman is also large and hairy, with mottled brown, white
and black markings. The eyesight of these spiders is not nearly as good as that of the
Salticidae. Nevertheless, their vision is quite sufficient to detect approaching humans
or other large animals from some distance. Habitat and distribution
Members of the Sparassidae are common in Australia, but also in many warm-temperate-to-tropical
parts of the world. They have been accidentally introduced to many parts of the world, including
South America,China, Philippines, Japan, India and southern parts of the United States, such
as Florida and Puerto Rico. A species of huntsman can be found in Hawaii, where it is commonly
known as a cane spider. In general they are likely to be found wherever ships may bring
them as unintended passengers to areas that are not too cold for them to survive in the
winter. In southern Africa they are commonly known as rain spiders because of their tendency
to seek shelter before rain storms, often entering human habitations when doing so.
As adults, huntsman spiders do not build webs, but hunt and forage for food: their diet consists
primarily of insects and other invertebrates, and occasionally small skinks and geckos.
They live in the crevices of tree bark, but will frequently wander into homes and vehicles.
They are able to travel extremely fast, often using a springing jump while running, and
walk on walls and even on ceilings. They also tend to exhibit a "cling" reflex if picked
up, making them difficult to shake off and much more likely to bite. The females are
fierce defenders of their egg sacs and young. They will generally make a threat display
if provoked, and if the warning is ignored they may attack and bite. The egg sacs differ
fairly widely among the various genera. For example, Palystes females generally suspend
large purses in bushes. The sac is reinforced with dead leaves and similar material; if
built indoors without disturbance, scraps of paper might be collected and used instead.
However, other genera build different sacs; Pseudomicrommata makes its nest in Eragrostis
grass and may be ecologically confined to regions where the grass grows. Females of
some species carry sacs in their jaws. Venom and aggression
Like most 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 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. Bites from Sparassids usually do
not require hospital treatment. In particular no necrosis was reported in the works cited
here. Sound production in mating rituals
Males of Heteropoda venatoria, one of the huntsman spiders that seems to easily find
its way around the world, have recently been found to deliberately make a substrate-borne
sound when they detect a chemical left by a nearby female of their species. The males
anchor themselves firmly to the surface onto which they have crawled and then use their
legs to transmit vibrations from their bodies to the surface. Most of the sound emitted
is produced by strong vibrations of the abdomen. The characteristic frequency of vibration
and the pattern of bursts of sound identify them to females of their species, who will
approach if they are interested in mating. List of genera
See also List of Sparassidae species
Table of spider families Spider wasp
Cultural depictions of spiders References
Abdullah Bayram & Sevda …Özdağ. "Micrommata virescens, a new species for the spider fauna
of Turkey". Turkish Journal of Zoology 26: 305–307.
External links Information page on Huntsman Spiders from
the Australian Museum Badge Huntsman Spider at Victorian Museum
Varieties of Sparassidae University of Southern Queensland – pictures & descriptions
Remarkable Australian Lichen Huntsman at American Arachnological Society
Heteropoda venatoria at University of Florida Institute of Food and Agricultural Sciences
Video of Olios sp. from Costa Rica