SPIDER

Spiders were among the earliest animals to live on land. Despite this their fossil record is relatively poor. They probably evolved about 400 million years ago from thick-waisted arachnid ancestors that were not long emerged from life in water. The first definite spiders, thin-waisted arachnids with abdominal segmentation and silk producing spinnerets, are known from fossils like Attercopus fimbriungus. This spider lived 380 million years ago during the Devonian Period, more than 150 million years before the dinosaurs.
Most of the early segmented fossil spiders belonged to the Mesothelae, a group of primitive spiders with the spinnerets placed underneath the middle of the abdomen (rather than at the end as in 'modern' spiders). They were probably ground dwelling predators, living in the giant clubmoss and fern forests of the mid-late Palaeozoic, where they were presumably predators of other primitive arthropods (like cockroaches, giant silverfish, slaters and millipedes). Silk may have been used simply as a protective covering for the eggs, a lining for a retreat hole, and later perhaps for simple ground sheet web and trapdoor construction.
As plant and insect life diversified so also did the spider's use of silk. Spiders with spinnerets at the end of the abdomen (Opisthothelae) appeared more than 250 million years ago, presumably promoting the development of more elaborate sheet and maze webs for prey capture both on ground and foliage, as well as the development of the safety dragline.
By the Jurassic Period (191 - 136 million years ago), when dinosaurs roamed the earth, the sophisticated aerial webs of the orb weaving spiders had developed to trap the rapidly diversifying hordes of flying insects. Similarly, the diversification of hunting spiders in litter, bark and foliage niches would have progressed in response to new prey-capture and habitat opportunities.
During the Tertiary Period the rich record of amber spider fossils - complete spiders trapped in clear, sticky, tree resins - show us that a spider fauna basically similar to that of the present day existed more than 30 million years ago.

What are the differences between spiders and insects?
Spiders have two main body parts, eight walking legs, simple eyes and piercing jaws (fangs), abdominal silk spinning organs, anterior abdominal genital opening.
Insects have three main body parts, six walking legs, compound eyes, antennae, chewing jaws (mandibles - often secondarily modified), posterior abdominal genital opening.
Spiders can't fly.
Many insects can fly.

FACTS FILE OF SPIDER

Can funnel-web spiders jump?
No. They rear up when disturbed, and bite with a fast downward action. They may rush forward aggressively, but they are not capable of propelling themselves off the ground.
What do funnel-web spider burrows look like?
Funnel-web burrows are distinguished from other holes in the ground by the presence of a series of irregular silk "trip-lines" radiating out from the entrance. Holes are normally found in moist, shaded areas like rockeries, dense shrubs, logs and leaf litter. A small, neat hole lined with a collar of silk which does not extend more than a centimetre from the rim could belong to a trapdoor spider (the common Brown Trapdoor Spider does not build a "door" for its burrow). Other possible hole owners include mouse spiders, wolf spiders or insects (most commonly cicadas or ants).
Photograph of a funnel-web burrow - funnel-web spider fact sheethttp://www.amonline.net.au/factsheets/funnelweb.htm
Why do funnel-web spiders wander (and end up in my house or swimming pool)?
Male funnel-webs leave their burrows to search for females in summer and autumn, and are normally active at night. The female funnel-web does not normally leave her burrow, but may be unearthed by excavations, rubbish removal or gardening, or be driven out by heavy rain. Wandering spiders are frequently encountered after a period of wet weather. Funnel-web spiders often fall into swimming pools. Spiders can trap a small bubble of air in hairs around the abdomen, which aids both breathing and floating, so it should not be assumed that a spider on a pool bottom has drowned. Funnel-webs have been known to survive 24-30 hours under water. Wandering spiders can enter houses at ground level, often under a door. Once inside a house, Funnel-web spiders will seek shelter to avoid drying out. Other large spider species such as the Brown Trapdoor and mouse spiders exhibit similar behaviour.
Information on control - Spiders in the House and Garden leaflethttp://www.amonline.net.au/factsheets/spiders.htm
Are huntsman spiders dangerous? They look so large and hairy...
Despite their often large and hairy appearance, huntsman spiders are not considered to be dangerous spiders. As with most spiders, they do possess venom, and a bite may cause some ill effects. However, they are quite reluctant to bite, and will usually try to run away rather than be aggressive. In houses they perform a useful role as natural pest controllers.
Some people may think of huntsman spiders as "tarantulas". However, they are not related to the large hairy ground dwelling spiders that are normally called tarantulas. Both huntsman spiders and tarantulas are often portrayed as being dangerous and scary. This usually is the case in films or stories that deliberately present spiders in a frightening and unrealistic way. If you feel frightened of huntsman spiders because of this, perhaps you might like to learn more about their true habits and biology. In this way you might be able to reduce your fears.
Huntsman spiders fact sheethttp://www.amonline.net.au/factsheets/huntsman_spiders.htm
How do you identify a wolf spider?
One of the diagnostic features of wolf spiders is their eye pattern which comprises three rows at the front of the carapace: four (smaller) eyes in the first row, two above the first and two above the second row. The diagram below (basically) shows this layout, face-on to the spider.
top
o oo o. . . .
bottom
Wolf spiders also have a variegated pattern on their bodies, often including radiating lines on the carapace and scroll-like patterns on the top of the abdomen. The underside of the spider is grey or black, sometimes with white markings. They can have orange spots on the sides of their jaws.
As Wolf spiders actively hunt for food they are likely to be found roving along the ground and they are more active at night. When spotlighted at night wolf spider's eyes will glow green. Scientists use this method during invertebrate surveys
Wolf spiders fact sheethttp://www.amonline.net.au/factsheets/wolf_spiders.htm
Does Australia have a bird-eating spider?
The term 'bird-eating spider' usually refers to large spiders from the family Theraphosidae. These spiders are also referred to as tarantulas. In Australia the theraphosids are represented by the whistling spiders (Selenocosmia sp.). These ground-dwelling spiders are big enough to prey on small frogs and reptiles, but are not known to eat birds. They are also known as barking spiders.
Museum of Victoria: Where did the barking spider get its name? http://www.museum.vic.gov.au/spidersparlour/faq.htm#barking
I have a pet whistling spider and want to know more about it...
There is more information about Selenocosmia species at the following websites:
South Australian Museum: Life and Adaptations to Water - Whistling spider Selenocosmia stirlingi http://www.samuseum.sa.gov.au/water/tesdes2.htm
The Whistling / Barking spider (Selenocosmia crassipes)http://www.arachnophiliac.com/burrow/whistling_barking_spider.htm
Queensland Bird-eating Spiderhttp://www.tenforward.com.au/spiders/
The Tarantulas.com website has general care information for large spiders, including spider first aid and how to deal with moulting: http://www.tarantulas.com/
Big Hairy Spidershttp://www.bighairyspiders.com/
More tarantula websites - Spider Linkshttp://www.amonline.net.au/spiders/resources/links.htm
Do we have tarantulas in Australia?
It depends on what you mean by the word "tarantula". Some people use it to describe the large hairy spiders of South and Central America. In Australia, the whistling spiders are also called tarantulas, as they are related to the American spiders. However, the word tarantula is also used to refer to huntsman spiders.
Tarantula is derived from the name of a town in Italy, Taranto. This town is the original home of the wild dance called the tarentella. During the Middle Ages, the tarentella was thought to be the way to cure the bite of a particular spider. The symptoms - known as tarantism - included severe pain, swelling, spasms, nausea and vomiting, palpitations, and fainting, along with exhibitionism, melancholia and delirium. It was hard to determine whether an actual bite had occurred or if people were merely displaying some form of madness or hysteria. Scientists later determined that many cases might indeed have been the result of a bite, although much of the fierce dancing and extreme behaviour may reflect more about the social and sexual repression at the time.
The alleged spider that caused all of these symptoms was called a tarantula, but the species was incorrectly identified. The original spider identified by the people of the time was a wolf spider (Lycosa tarantula). However, it was subsequently shown to cause little serious results when it bit people. Finally, it was shown that the real culprit was a Black Widow relative, Latrodectus tredecimguttatus, known in Southern Europe as the "malmignatte". The symptoms of this spider's bite (and of other Latrodectus species, including the Redback Spider) match the whole-body symptoms experienced during tarantism.
Information from Hillyard, P. 1994. The Book of the Spider. Hutchinson, London.
To learn about the history of the word "tarantula", and its origins, have a look at:
Tarantism episodes in Lizzano, Italyhttp://www.ba.infn.it/~zito/taranta.html
Article: Rethinking the dancing maniahttp://www.csicop.org/si/2000-07/dancing-mania.html
More tarantula websites - Spider Linkshttp://www.amonline.net.au/spiders/resources/links.htm
Do we have scorpions in Australia?
Yes we do. Scorpions are common in gardens and forests throughout eastern Australia and are found under logs, rocks and in shallow burrows in earth banks. They are nocturnal - which is why we rarely see them - but they can be disturbed during the day, especially during the prolonged wet weather. There are also species that live in the desert and others that inhabit tropical rainforests.
Scorpion Fact Sheethttp://www.amonline.net.au/factsheets/scorpions.htm
How does spider venom work in humans?
Venoms are chemicals of biological origin (i.e. made by an animal) used for the purpose of attack or defence. Venoms are made by specialised organs, such as modified salivary glands, and are delivered via specialised systems such grooved or hollow fangs. Most venoms consist of a complex mixture of chemical substances, including proteins, peptides, sugars and other substances. Venoms may affect many systems of the body. Common venom effects include paralysis, interference with blood clotting, breakdown of muscle, pain, breakdown of tissues and effects on the cardiorespiratory system (the heart and lungs).
There are basically two types of venom that have an effect on humans: neurotoxic and cytotoxic or necrotic venoms. Neurotoxic venoms work directly on the nervous system. The best known example is the venom of the Black Widow/Redback spiders (Latrodectus species). Necrotic venoms cause damage to the tissues, such as blisters and lesions. A good example is the venom of the White-tailed Spider (Lampona cylindrata). Generally, neurotoxic venoms kill more quickly than necrotic venoms.
The main effect of a neurotoxic venom is to block nerve impulses to the muscles, causing cramps and rigidity. It also overstimulates the production of the neurotransmitters, acetylcholine and norephinephrine, causing paralysis of the entire nervous system. The combined effect causes sudden and severe stress to the entire human body. Funnel-web Spider venom - known as atraxotoxin - acts directly upon the nervous system in this way.
Necrotic venoms cause skin blisters around the site of the bite, which may lead to ulcers and tissue death - necrosis. The widespread Recluse Spiders are the most toxic of the spiders that possess necrotic venom. The introduced species Loxosceles rufescens is present in Australia. Bites from some wandering spiders, including the White-tailed Spider, Wolf Spiders and the Sac Spiders (Cheiracanthum species) can also cause necrosis, but severity varies from little to acute reactions. Scientists are still determining which species cause most problems, as many spiders involved in necrotic bites have been misidentified in the past.
Venoms are complex substances, made up of several components, including proteins, sugars.
Venom links
Spider bites and venomshttp://www.amonline.net.au/spiders/dangerous/bites/index.htm
International Venom and Toxin Databasehttp://www.kingsnake.com/toxinology/
Australian Venom Research Unit (AVRU): Venoms and Antivenomshttp://www.pharmacology.unimelb.edu.au/avruweb/index.htm
What is the world's most dangerous spider?
It is hard to define which spider in the world is the most dangerous to humans. Several spiders could qualify, depending on what you mean by dangerous. Do you mean the spider with the most toxic venom, measured by its effect on newborn mice or other mammals? Or do you mean the spider that has caused the death of the most people? Those that have the strongest venom may not be encountered by humans very often, or may even have trouble piercing human skin and so are not considered to be "dangerous". Data are usually only kept on bites from spiders that are potentially deadly or cause severe reactions and these data are not recorded consistently at a national or international level. Here, we will define dangerous as "deadly".
In summary, on current evidence the most dangerous spiders in the world are funnel-web spiders (Atrax and Hadronyche species), Redback Spiders and their relations (Latrodectus species), Banana Spiders (Phoneutria species) and Recluse Spiders (Loxosceles species). In Australia, only male Sydney Funnel Web Spiders and Redback Spiders have caused human deaths, but none have occurred since antivenoms were made available in 1981.
The Australian funnel-web spiders are among the deadliest spiders in the world in the effect their bites have on humans and our primate relations (although the bite has little effect on dogs and cats). There are many species of funnel-web spiders in Australia but only male Sydney Funnel-webs have caused human deaths. There have been only 13 deaths recorded from male Sydney Funnel-webs, but up to 30-40 people are bitten by funnel-web spiders each year. Mouse spiders may have venom that is as toxic as that of some funnel-webs, as some patients have had severe reactions to their bites, although no-one has been recorded as having died from the effects of a mouse spider bite. Antivenoms are available for both funnel-web and Redback Spider bites.
A group of spiders that is dangerous in many countries belongs to the genus Latrodectus in the Family Theridiidae. In Australia we have the Redback Spider (Latrodectus hasselti). In America, a common representative of this genus is the Black Widow (Latrodectus mactans). Antivenoms are available for both funnel-web and Redback Spider bites.
A deadly spider which comes from South America is the Banana Spider, Phoneutria species. In south-eastern Brazil between 1970 and 1980, more than 7,000 people were admitted to hospital with bites from this spider. An antivenom also exists for this species.
The Recluse or Fiddleback Spider is a deadly spider belonging to the genus Loxosceles. Recluse spiders are found in many parts of the world and have been introduced into Australia. The venom of this spider can cause severe skin necrosis (eating away of the flesh) and can be fatal although not many deaths have been recorded.
How many dangerous spider bites occur in Australia each year? Has anyone died from a bite recently?
There have been no deaths in Australia from a confirmed spider bite since 1979. An effective antivenom for Redback Spiders was introduced in 1956, and one for funnel-web spiders in 1980. These are the only two spiders that have caused deaths in Australia in the past.
A spider bite is not a notifiable medical emergency, so there are no Australia-wide statistics, but the following figures give an idea of the incidence of reported bites in recent years.
Approximately 2000 people are bitten each year by Redback Spiders
Funnel-web spider antivenom has been given to at least 100 patients since 1980. Antivenom is given only when signs of serious envenomation are observed. Many spider bites are 'blank', which means that no venom has been injected.
During 2000 the New South Wales Poisons Information Centre received 4,200 calls about spiders. However not all of these would have involved actual bites. Many reported bites are not able to be identified as definitely being from a spider, and it is nearly impossible to work out what species has caused a bite without seeing a specimen of the spider responsible.
Figures are from:
Sutherland, S K and Nolch, G (2000) Dangerous Australian Animals. Hyland House, Flemington, Vic. 201 pp. ISBN 86447 076 3
NSW Poisons Information Centre The Children's Hospital at Westmead Locked Bag 4001 Westmead, NSW 2145 Emergency Phone: +612 9845 3111 Administrative Phone: +612 9845 3599 Fax: +612 9845 3597
What spiders in Australia may cause ill effects if they bite you?
In Australia, bites from at least two kinds of spiders - wolf spiders and white-tailed spiders - in some cases cause skin necrosis (eating away of the flesh). However, neither spider has caused human deaths. There are also a number of others which are thought to cause the same problem, but research is still being done to find out exactly which species do so.
Bites from many Australian spiders can cause localised reactions, with symptoms such as swelling and local pain at the site of the bite, sweating, nausea and vomiting and headaches. All of these symptoms will vary in severity depending on the age of the victim, their health, and the amount of venom that the spider was able to inject. Have a look at our spider fact sheets to find out more about individual species.
Do white-tailed spiders cause the skin condition known as necrotising arachnidism?
There is an ongoing debate among toxicologists and spider biologists about the effects and dangers of white-tailed spider bites. Most of these bites appear to cause little or no effect beyond transient local pain. However a small number of cases do cause more extensive problems. Whether this is a result of the spiders' venom or to bacteria infecting the wound at or after the time of the bite has not yet been resolved. It is also possible that some people may react badly to white-tailed spider bite, possibly because of immune system susceptibility or a predisposing medical condition.
Links
White-tailed spider fact sheethttp://www.amonline.net.au/factsheets/white_tailed_spider.htm
Medical Journal of Australia: A comprehensive summary of current knowledgehttp://www.mja.com.au/public/issues/171_2_190799/pincus/pincus.html
An article by Dr Julian Whitehttp://www.mja.com.au/public/issues/171_2_190799/white/white.html
An article by Chan and Dr White's responsehttp://www.mja.com.au/public/issues/xmas98/chan/chan.html
Clinical Toxicology page by Julian Whitehttp://www.wch.sa.gov.au/paedm/clintox/
The University of Melbourne's Australian Venom Research Unit (AVRU)http://www.pharmacology.unimelb.edu.au/ pharmwww/avruweb/aboutav.htm
References
Meier, J. & White, J. (1995) Handbook of Clinical Toxicology. CRC Press, Florida USA.
Whitehouse, R. (ed.) (1991) Australia's Dangerous Creatures Readers Digest Pty Ltd, Surry Hills NSW.
Sutherland, S. & Sutherland, J. (1999) Venomous Creatures of Australia Oxford University Press, South Melbourne.
Isbister,G. & Greay,M. (2000). "Acute and recurrent skin ulceration after spider bite" Medical Journal of Australia 172, 20 March 2000, pp.303-304
How do I control white-tailed spiders around the house?
Beyond killing or removing all white-tailed spiders that you encounter, you can try a prey reduction strategy. White-tailed spiders like to feed on Black House Spiders (Badumna insignis) in particular, but will take other spiders too. This means that you should clean up obvious spiders around the house (outside and in). This involves removing spiders from around windows, walls and verandas (by web removal and/or direct pyrethrum spray). The condition of the roof cavity and the underfloor area (if raised) should also be investigated. (from Mike Gray, Arachnologist, Australian Museum)
What is the biggest spider in the world?
The biggest spider in the world is the Goliath Spider, Theraphosa leblondi. It lives in coastal rainforests in northern South America. Its body can grow to 9 cm in length (3.5 inches) and its leg span can be up to 28 cm (11 inches). (from: Carwardine, M. 1995. The Guinness Book of Animal Records. Guinness Publishing.)
What is the biggest spider in Australia?
Australia's biggest spiders belong to the same family as the Goliath Spider. They are the whistling spiders. The northern species Selenocosmia crassipes can grow to 6 cm in body length with a leg span of 16 cm.
What is a Daddy-long-legs?
'Daddy-long-legs' is the common name for a particular group of spiders, but it is also used for a different group of arachnids - the harvestmen or opilionids. As a result, there is a lot of confusion about what people mean when they say 'daddy-long-legs'.
Daddy-long-legs: spiders The animal which most biologists call Daddy-long-legs, is a spider, Pholcus phalangioides, which belongs to the spider family Pholcidae, order Araneida, class Arachnida. It has two parts to the body, separated by a narrow waist. It has eight eyes and eight very long thin legs. Pholcids often live in webs in the corners of houses, sometimes in bathrooms. Daddy-long-legs spiders (or pholcids) kill their prey using venom injected through fangs. Digestion is external, with fluids being squirted onto the prey item and the resulting juices sucked up by the spider.
Daddy-long-legs: harvestmen The other eight-legged invertebrates that are sometimes called Daddy-long-legs, are members of the order Opiliones or Opilionida in the class Arachnida. Another common name for these arachnids is 'harvestmen'. Unlike spiders, their bodies do not have a 'waist', they do not produce silk and they normally have only one pair of eyes. They do not have venom glands or fangs, although they may produce noxious defence secretions. Most harvestmen eat smaller invertebrates but some eat fungi or plant material and others feed on carcasses of dead mammals and birds. Digestion is internal and some solid food is taken in, which is uncharacteristic for arachnids. You usually do not find harvestmen inside houses.
Are Daddy-long-legs the most venomous spiders in the world?
There is no evidence in the scientific literature to suggest that Daddy-long-legs spiders are dangerously venomous. Daddy-long-legs have venom glands and fangs but their fangs are very small. The jaw bases are fused together, giving the fangs a narrow gape that would make attempts to bite through human skin ineffective.
However, Daddy-long-legs Spiders can kill and eat other spiders, including Redback Spiders whose venom can be fatal to humans. Perhaps this is the origin of the rumour that Daddy-long-legs are the most venomous spiders in the world. The argument is sometimes put that if they can kill a deadly spider they must be even more deadly themselves. However this is not correct. Behavioural and structural characteristics, such as silk wrapping of prey using their long legs, are very important in the Daddy-long-legs' ability to immobilise and kill Redbacks. Also, the effect of the Daddy-long-legs' venom on spider or insect prey has little bearing on its effect in humans.
This myth is also debunked at the following web site:
University of California Riverside Department of Entomology: Daddy-longlegs Mythhttp://spiders.ucr.edu/daddylonglegs.html
What are banana spiders and where are they found?
Banana spider is the common name given to large (3 cm body length) active hunting spiders of the genus Phoneutria (Family: Ctenidae). These spiders live in Central and South American rainforests. They are often found in rubbish around human dwellings, as well as hiding in foliage such as banana leaves where they sometimes bite workers harvesting bananas. They have a reputation for being quite aggressive.
Other names for this spider include: Kammspinne, Bananenspinne, Wandering spider, and Aranha armadeira.
The venom of this spider is neurotoxic - acting on the nervous system - and causes little skin damage. Symptoms of a bite include immediate pain, cold sweat, salivation, priapism, cardiac perturbations and occasional death. Research suggests it is similar in action to a-latrotoxin, which is produced by spiders of the Family Latrodectidae, such as the Redback and Black Widow Spiders.
For more information about spider bites:
NetDoctor: Scorpion stings and spider bites (mentions Banana Spider)http://www.netdoctor.co.uk/travel/diseases/scorpions_and_spiders.htm
Another spider that seems to have been given the common name "banana spider" is actually a completely unrelated species of orb weaving spider from Florida. This is a good example of why it is more useful to use scientific names when you are trying to find information on different animals or plants.
Florida's Golden Silk Spider(Nephila clavipes) - also known as a Banana Spider:http://pelotes.jea.com/spiders.htm
How do I find out about spiders in New Zealand?
The following New Zealand arachnologist (spider biologist) has offered to respond to inquiries from people interested in New Zealand spiders:
Dr Phil SirvidEntomology Section Museum of New Zealand Te Papa Tongarewa PO Box 467 Wellington, New Zealand ph: +644 381 7362 fax: +644 381 7310 email: Phils@tepapa.govt.nz
There is a book on New Zealand spiders:
Forster, Ray and Lyn. 1999. Spiders of New Zealand and Their Worldwide Kin. University of Otago Press, ISBN 1 877133 79 5
What about white-tailed spiders in New Zealand?
Dr Phil Sirvid has this to say about white-tailed spiders in New Zealand:
"We have two species of white-tails in New Zealand - Lampona cylindrata and Lampona murina. They are both very similar in appearance, and can really only be separated from one another by viewing them under a microscope and examining certain features that aren't apparent to the naked eye.
Both have been introduced from Australia.
L. murina has been in the North Island of New Zealand for [over] 100 years, and has also been introduced to the Kermadecs, Lord Howe Island and Norfolk Island. I wouldn't be surprised if it's in the Chatham Islands as well. In Australia, this species is recorded along the East Coast from northern Queensland down through New South Wales and Victoria.
L. cylindrata had only been found occasionally in the South Island until the 1980s. About this time it seemed to spread rapidly throughout the South Island's main urban centres, and is known to occur as far south as Dunedin. This species is found along the southern part of Australia from Western Australia, through South Australia, Victoria and Tasmania, as well as in New South Wales and Queensland."