Huntsman spider

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{{Taxobox | color = pink | name = Huntsman spiders | image = Huntsman spider.jpg | image_width = 200px | image_caption = Huntsman spider | regnum = Animalia | phylum = Arthropoda | classis = Arachnida | ordo = Araneae | familia = Sparassidae | familia_authority = Bertkau, 1872 | subdivision_ranks = Genera | subdivision = Delena (Flat huntsman spider)
Heteropoda (Brown huntsman spider)
Holconia (Banded huntsman spider)
Isopeda
Isopedella
Neosparassus (Shield hunstman spider)
Pediana
Numerous others, see links
}}

Huntsman spiders is a common name given to the family Sparassidae (formerly Heteropodidae). These spiders are found in Australia, New Zealand, South-east Asia, the Middle East in areas near the Mediterranean Sea, Florida and Hawaii in the US, and quite possibly in many other tropical and semi-tropical areas.

1 Appearance
2 Habitat and distribution
3 Toxicity and aggressivity
4 Sound production in mating rituals
5 Gallery
6 External links

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Appearance

While frequently very large – in Laos, Heteropoda maxima males can attain a legspan of 25–30 cm (9.8–11.8 in) – and quite a fearsome sight, they are not deadly to humans. They do bite if provoked, but the victim will suffer only minor swelling and localised pain and will recover in a day or so. Some larger types resemble tarantulas, and may be mistaken for them, but the huntsman is unrelated (though the term "Australian tarantula" has sometimes wrongly been used to describe them — even by the Natural History Museum in Sydney). Huntsmen generally can be identified by their legs, which rather than being jointed vertically relative to the body, are twisted such that the legs extend forward in a crab-like fashion.

Many, but certainly not all, huntsman spiders are dull shades of brown or grey. Their legs are covered with fairly prominent spines, but the rest of their bodies appear smooth but not shiny. They are frequently found in sheds, garages and other infrequently disturbed places. The banded huntsman (Holconia) is larger, grey to brown with striped bands on its legs. The badge huntsman (Neosparassus) is larger still, brown and hairy. Its bite will inflict the worst injury, as well as local swelling and pain may cause nausea, headache, vomiting and heart palpitations. The tropical or brown huntsman (Heteropoda) 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 (jumping spiders). Nevertheless, their vision is quite sufficient to detect approaching humans or other large animals from some distance.

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Habitat and distribution

Members of the Huntsman family of spiders are very common in Australia, but also in many tropical and semi-tropical parts of the world. They are now found in many parts of the world to which they may not be native, including China, Japan, the southeast part of America, such as Florida and Puerto Rico, and also the southwestern part of the country. 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 wintertime.

As adults, Huntsmen do not build webs, but forage for food; primarily insects and other invertebrates. They live in the crevices of tree bark, but will frequently wander into homes and cars. They are able to run extremely fast, and travel on walls and even on ceilings, having quite a good ability to adhere to smooth surfaces. They also tend to exhibit a "cling" reflex if you attempt to pick them 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, but if the warning is ignored they may attack and bite.

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Toxicity and aggressivity

In general, Huntsman spiders are not regarded as dangerous. There are however reports of members of the genus Neosparassus (formerly called Olios) giving bites that have caused prolonged pain, inflammation, headache, vomiting, and irregular pulse rate. It is unclear under what circumstances these spiders bite people, but it is known that female members of this family are quite brave in defending their egg sacs and their young.

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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 sound when they are given reason to believe that females of their species are nearby. Their method of making sounds is unlike methods already observed in other species of spiders. The males anchor themselves firmly to the surface onto which they have crawled and then use their legs to vibrate their entire bodies. It appears that most of the sound emitted is actually produced by the strong vibrations of the two rearmost pairs of legs. The characteristic frequency of vibration and the pattern of bursts of sound seem to identify them to females of their species, who will approach if they are interested in mating [1].

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