Suborder of mastmoths - general family of six-warty spiders
Eukaryotic domain
animal kingdom
Subkingdom of eumetazoa
Ecdyanimal main phylum
Arthropod phylum
Subphylum Chelicera
Arachnids (Arachnida)
Araneae
Suborder Mammoth
Six warty spiders
There are two families under the family Hexathelidae, the six warty spiders together with the spiders under the long-tailed spider family are called "funnel-webs", which are nocturnal, and some species of venom can threaten human life, and the other family is called Australian funnel-web spiders (family name: Atracidae).
In fact, until 1980, because the hexawart spider family was only a posterior spinner, and some other features were slightly different from the long-tailed spider family, it was regarded as a subfamily of the latter.
1. Distribution
Most of the organisms are found in Australia, New Zealand and Asia. One species is found in the Mediterranean, two in South America, and two species now exist in central Africa.
2. Subordinates
Hexathelidae
Subfamily Hexathelinae
Arachnidae
Subfamily Atracinae
3. Six warty arachnidae
Hexathelidae (scientific name: Hexathelidae), also known as hexatheloidea, is the only two families under the hexatheloidea, together with the spiders under the long-tailed spider family is called "funnel-webs", with nocturnal nature, and some species of venom can threaten human life.
Most of the organisms are found in Australia and New Zealand, and two genera are found in Argentina and Chile in South America.
Creatures of the family Cerambycidae live mainly in caves, including crypts and tree holes. They weave cobwebs in burrows to catch prey, and often dig burrows in human dwellings, where spiders are found in rainforests.
4. Venomous arachnidae
The subfamily Atracinae, also known as the Australian funnel-web spiders (common name: Australian funnel-web spiders, subfamily name: Atracinae), is the only subfamily of the family Atracinae. Studies have repeatedly questioned the taxonomic status of the group, often finding that they are related to the Actinopodidae family. All members of this subfamily are native to Australia and consist of three genera: Atrax, Hadronyche and Illawarra, comprising 35 species. Many species produce venom that is dangerous to humans, and spider bites in six of these species can cause serious injury to victims. Bites from Sydney funnel web spiders (Atrax robustus) and northern arboreal funnel web spiders (Hadronyche formidabilis) can be fatal, but there have been no fatalities since the introduction of modern first aid techniques and antivenoms.
(1) Habit distribution
A funnel-shaped spider that lives on the outskirts of Sydney, Australia. Bitten by it, you will die within 15 minutes. It is considered the most toxic spider, with fangs strong enough to penetrate human fingernails. Unlike most spiders who lead a quiet life, this little one is extremely aggressive, raising its hind legs when disturbed and constantly biting its victim. Although male spiders are smaller than females, their venom is 5 times more toxic than females. Remember: when you go to the toilet in Australia, be careful to touch the toilet seat, because that's where poisonous spiders like to stay.
Funnel-shaped spiders prefer to hide in dark, damp, cool places such as: under rocks, under piles of rotting leaves, cracks in logs, and shady corners of jungles. However, in the garden, they will only perch in the crevices of rockeries, or in thick piles of leaves, and will not be seen in open places such as lawns. Most funnel-shaped spiders extend their irregular webs from their territory, and the center of the web is stationed by the owner of the territory. These cobwebs can convey a variety of messages to the owner, the fall of the prey, the arrival of a mate, and the arrival of danger.
Rainy weather sometimes washes away their habitats, which makes male spiders work hard to rebuild their homes, and they are more motivated to do so. Because the biggest weakness of funnel-shaped spiders is that they cannot adapt to dry environments, so that humid environments will make them feel more comfortable and energetic. Night naturally becomes a time of frequent activity. However, throughout the year, funnel-shaped spiders can always be seen when repairing the garden.
(2) Mating and reproduction
The female spider spends almost her life in her nest, although there are times when she goes out, and almost at night, the female spider will go out of her nest to hunt for food. Male spiders leave their territory to date female spiders when they reach adulthood, especially in summer and autumn. Male spiders spend almost all of their adult life mating with other suitable female spiders as much as possible, crawling into people's dwellings through gaps in windows and doors, looking for mates. As a result, this season becomes the peak period for conflicts between humans and spiders.
Male funnel-shaped spiders will look for the hidden nest of female spiders through the sex hormone smell emitted by female spiders, and during mating, male spiders should be very careful to avoid the stingers on the second pair of legs of female spiders, and introduce the seminal ducts into the fertile sac of female spiders, which is a thrilling process.
After mating, the female spider will spin a different kind of web from the hunting web - a pillow-shaped web - in which more than 100 eggs will be placed. They are then cared after during the incubation period, and if danger strikes, the female will desperately protect her baby. After three weeks, the new generation will emerge, the young spiders will live with their mother in the nest for a few months, after two hair changes, they will leave their mother to find a place to live, until the final hair change they become adult spiders, and the male spiders will live in adulthood, looking for female spiders to mate.
Funnel-shaped spiders take 2 to 4 years to grow into adult spiders, females can live up to 10 years or more, while male spiders can only die 6 to 9 months after mating.
(3) Toxicity
The main component of venom is atraxotoxin, which is toxic to primates and dogs, and non-toxic to rabbits. Atraxotoxin causes changes in the membrane potential of nerve cells, so that the autonomic nervous system secretes a large amount of acetylcholine, epinephrine, and n-adrenaline. Male spiders are about 4 times more toxic than female spiders. The reason may be that male spiders need to leave the nest to find mating partners during the reproductive season, while female spiders do not; Because spiders lose the protection of the web when they leave the nest, they are very vulnerable to attack, and they evolve strong toxicity under the pressure of natural selection. The symptoms of a funnel web spider bite depend on whether the spider releases a large amount of toxins. In the local area, there will be severe pain, redness, hair erection, sweating; Characteristics like latrodectism; Systemic symptoms include nausea, vomiting, abdominal pain, diarrhea, sweating, salivation (within 10 minutes), tearing, tightness, dyspnea, pulmonary edema, rapid heartbeat, arrhythmia, fever, and dyspnea caused by hydrops is the main cause of death.
Funnel-shaped spiders are attacked in summer and autumn, because these are the time when males look around for females to mate, so watch out for gardens, houses, garages, and open areas in houses, and be careful of bumping into them.
After being bitten by a funnel-shaped spider, venom can cause severe discomfort and even death, because these venoms are particularly effective against primates, so it is difficult for humans to resist these venoms themselves.
Male Sydney funnel-shaped spiders are many times more toxic than females, because the venom of Sydney funnel-shaped male spiders can severely damage the nervous system of primates (including humans), which is the most toxic male spider found so far. After being bitten, there will be a little pain in the bitten area, followed by numbness in the mouth, vomiting, abdominal pain, and sweating. However, humans have developed antiserum for this toxin, which can be very effective in preventing the damage of the toxin to humans.
(4) Medical significance
The Australian funnel-web spider is one of the most dangerous spider populations in the world and is considered the deadliest in terms of the number of clinical cases and the toxicity of the venom. Six of these species have caused serious harm to people, including the Sydney funnel web spider (Atrax robustus), the northern arboreal funnel web spider (Hadronyche formidabilis), the southern arboreal funnel web spider (H. cerberea), the Blue Mountains funnel web spider (H. versuta), the Darling meadow funnel web spider (H. infensa) and the Macquarie Port funnel web spider (H. smith). macquariensis）。
Biting record studies have shown that wandering male spiders account for the vast majority, if not all, of all fatal bites to humans by funnel-web spiders. Adult male spiders can be identified by the ends of different tentacles, and they often roam the ground during the warmer months of the year, looking for females to mate with. They are attracted to water sources and often fall into pools while loitering, so they are often found in swimming pools. These spiders can sometimes survive being immersed in water for hours and can bite when removed from the water, and they are also often found in garages and yards in suburban Sydney. They actively defend themselves when they feel threatened. Contrary to popular belief, funnel nets can run fast, but they cannot jump.
Although some highly toxic funnel web spiders do not usually inject venom when they bite, most of them do. Large animals are usually bitten with a small amount of venom, most likely due to the angle of the fangs, whose fangs are not horizontally opposed, and in fact they are lost after a short bite. About 10% to 25% of bites are considered to be extremely toxic, and since this possibility is unpredictable, all bites are considered life-threatening. Funnel web spiders are not usually aggressive, but they will be actively defensive when frightened or threatened. When attacking, funnelweb spiders usually cling tightly to the target for repeated bites, which becomes a particularly painful experience for the target and increases the risk of fatal venom stings.
Sydney funnel web spiders have killed 13 people (7 of them children). In all the cases where the sex of the biting spider could be determined, it was found to be a male spider. The northern arboreal funnelweb spider is a type of funnel spider that is thought to be able to cause deadly venom infusions. But so far, this has been supported by special medical reports. Articles on the venom of northern arboreal funnel-web spiders indicate that several Sydney funnel-web spiders are similar to its venom.
(5) Symptoms
The symptoms of poisoning after the bite of these spiders are very similar. Due to the size of the fangs pierced into the skin, the initial bite is very painful. Marks of penetration and local bleeding are usually seen. If a large venom infusion occurs, symptoms usually appear within a few minutes and develop rapidly.
Early symptoms of systemic venom infiltration include goosebumps, sweating, tingling around the mouth and tongue (initially on the face and between the ribs), salivation, increased tear production, rapid heartbeat, and increased blood pressure. As systemic venom infiltration progresses, subsequent symptoms include nausea, vomiting, shortness of breath (due to airway obstruction), restlessness, confusion, rolling, distressed expression, muscle cramps, pulmonary edema (due to neuropathic or hypertension), metabolic acidosis, and severe hypertension. The final stages of severe venom infiltration include mydriasis (usually fixation), uncontrolled generalized muscle twitching, loss of consciousness, increased intracranial pressure, and death. Progressive hypotension or a possible rise in intracranial pressure due to cerebral oedema usually results in death.
The onset of severe venom infusion is rapid. In one prospective study, the median time to venom infiltration was 28 minutes, with only two cases occurring after two hours (pressure fixing bandages were used in both cases). Deaths range from 15 minutes (when a child is bitten) to three days.
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