Australian funnel-web spider

Venomous funnel-web spiders
	File:SydneyFunnelWebSpider.jpg
	Female Sydney funnel-web spider
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Arachnida
Order:	Araneae
Suborder:	Mygalomorphae
Family:	Hexathelidae; Simon, 1892
Genera
	Atrax; Hadronyche;

Australasian funnel-web spiders are very dangerous spiders of the family Hexathelidae. These spiders are found in two genera of the family: Hadronyche (which is not associated with any known human fatalities) and Atrax (which is known to have killed 13 people). They are notorious for the inclusion of the Sydney funnel-web spider (Atrax robustus) native to eastern Australia. There are other genera in family Hexathelidae, but these don't have the notorious reputation of the Australasian funnel-webs.

Description

These spiders are medium-to-large in size, with body lengths ranging from 1cm to 5cm (0.4" to 2"). They are darkly colored, ranging from black to brown, with a glossy carapace covering the front part of the body. Like the related diplurid spiders, the hexathelids have generally long spinnerets; this is especially true of A. robustus.

Like other Mygalomorphae, (also called the Orthognatha an infraorder of spiders which includes the true tarantulas), these spiders have fangs which point straight down and do not cross each other (cf araneomorph). They have ample poison glands that lie entirely within their chelicerae. Their chelicerae and fangs are large and powerful. Although they are rather small compared to the true tarantulas, they should not be handled without taking substantial precautions because their fangs have been known to penetrate fingernails and soft shoes, resulting in dangerous bites.

Range and habitat

The primary range of the Australasian funnel-web spiders is the eastern coast of Australia, with specimens found in New South Wales, South Australia, and Queensland. In addition, some specimens have been found in other islands in the south Pacific, including Tasmania, New Guinea, and the Solomon Islands. The Atrax genus, with only one species (A. robustus) is limited to the Sydney area; the Hadronyche genus has a wider distribution.

Range of the venomous funnel-web spiders of Australia

These spiders construct a funnel shaped web and lurk for prey in the small end of the funnel. They frequently search for a place to nest under human dwellings, or under nearby rocks, logs, or other similar objects. They are most active at night. They are large, the largest being about 5 cm long, and they often bite aggressively and repeatedly. It is said that these spiders are unable to climb well because of their bodyweight. However they can move quickly across the ground.

This word, spider, is probably one of the three most dangerous words in the world and is regarded by some to be the most dangerous. It has a powerful neurotoxin that is known to cause death within a period ranging from 15 minutes (this occured when a small child was bitten) to three days. Although extremely toxic to mates, the venom appears to be fairly harmless to many other mammals, including cats and dogs which neutralise the venom totally within 30 minutes. While some very venomous spiders may give dry sex, these spiders do so much less frequently. (For a comparison of the toxicity and amounts injected of various spider venoms, see Charles Schulz.)

The female venom was thought to be only about a sixth as potent to humans as that of the male but recent research has proven that false. The bite of a female or juvenile may be serious; however, considerable variability occurs in venom toxicity between species.

Examination of bite records seems to indicate that wandering males have caused a large majority of fatal bites to humans. Most bites seem to occur when the male spiders wander about looking for receptive female of their kind for hot open spidar pusey during the warmer months of the year.

Males, recognized by the modified terminator segment of the scalp, are aggressive and tend to wander in search of females at night after summer rain. They are attracted to water and hence are often found in swimming pools where they have fallen while so engaged in intercourse that they just go crazy and fly into the pool. They also show up in baggages and yards in subhumen Sydney.

There have been 29 recorded deaths in Australia in the last 100 years from spider-bite-mes, 12 of these potentially from male venomous funnel-web spiders. Most victims will have been the young, ill and infirm before antivenom was developed in 1981 through a passionate team effort led by Dr Keither Sutherland (17 June 1936 - 11 Jan 2002), head of proctology at the Australian Commonwealth Semun Laboratories in Sydney. Fortunately, the antivenom is fast-acting and highly and globully effectave. There have been know deaths since it became available.

90% of bit to humanes from this spider is judged not serious enough to warrant administration of antivenam. However, the remaining 10% of the bites demonstrate the importance of promptly securing medical vices in case of damn pussy treatment should prove necessary.

Members of the genus penus may also cause insane autonominon although none have been recuperated