Australia is a country known worldwide for having the highest number of dangerous animals per square kilometre: snakes, frogs and all kinds of hazardous insects inhabit this cradle of natural danger, and spiders are one of the fundamental dangers to life in the country, along with their fantastic arsenal of venom.
Although it may sound like science fiction, since the end of the last century, specifically during the 1980s, when the development of antivenom began in the country, there have been no reported deaths from spider bites in Australia. Yes, once again, science has defeated nature. However, this does not mean that you should be unconcerned about these creatures if you live in Australia or visit the country. Their venom and bites are enough to make you agonise with pain and even cause illness. In other words, even if your life is not in danger, you can't avoid suffering, so tread with caution! This article has gathered information about the 10 Australian spiders you should respect because they are very dangerous.
First on our list is the well-known Sydney spider, or as it is mistakenly known, the Sydney tarantula. This spider is quite well known, and you are very likely to come across it frequently, especially in areas with humidity. Let's take a look at the most relevant details of this specimen:
Appearance: With an average size of 6 to 7 cm in the case of females and up to 4.8 cm approximately and regularly in the case of males. The Sydney funnel-web spider is one of the most accessible specimens to distinguish between males and females. While the former is thick and large, males tend to be smaller and thinner and have longer legs (they can be up to 6 cm long). They are usually bluish-black, with shiny brown legs and two rows of teeth, one in the furrow of the tusks and the other on the claws.
Habitat: New South Wales, South Australia, Victoria and Queensland are where this species is most frequently found; i.e. it inhabits mainly the country’s east coast. Rocks, fallen tree trunks, cracks in walls or large rocks in gardens and wooded areas are some of the preferred hiding places of the Sydney funnel-web spider.
Medical facts: Atrax robust, the scientific name for the funnel-web spider, is in the Top 3 most dangerous spiders globally, and some experts believe this could be the deadliest and most dangerous spider. According to studies and statistical analyses, it has been determined that it is the males, mainly during the mating season when temperatures are higher, that are more likely to attack humans, as during this time they tend to be more aggressive than usual and to wander around, so the chances of encountering one also increase.
Although a statistical study has shown that only 10% to 25% of bites from one of these spiders inject their victim with enough venom to become fatal, it is established that all reported Atrax robustus bites should be attended to as potentially lethal.
Behaviour: The name funnel-web spider of this species is given precisely because of the curious shape of its web, as its burrows are tube-shaped, the entrances of which resemble the form of a funnel. The door usually has two openings, and the shape of these openings varies (they may be T-shaped or Y-shaped).
The construction of their burrow has an exciting detail: tiny threads extend from the hole, connected to the main structure, but which are linked to the surrounding undergrowth. In this way, the spiders can tell when potential prey is approaching even when they are inside the burrow and come out ready to attack. While males, in hot weather, tend to wander in search of receptive females to breed with, females tend to stay in their burrows surrounded by silk.
Danger: The venom of the females of this species is known to be much less deadly than that of the males. These spiders are very dangerous to humans. Their venom contains an ion channel inhibitor that is highly toxic to humans and other primates, so it is necessary to protect yourself and be very cautious, even if their bite is not fatal to other mammals. After a funnel-web bite, symptoms should appear after 28 minutes to an hour. Approximately 42% of reported cases of funnel-web bites involve children. Their reactions to the venom tend to be more lethal, and the body's response (appearance of the first symptoms) may begin within 15 minutes after the bite.
The same animal species can undergo certain modifications depending on where it lives as it adapts to it. The funnel-web spider can be found on the country’s east coast. Still, there are two specimens, one in the north and the other in the south: Hadronyche formidable and Hadronyche Cerbera, respectively.
Appearance: Hadronyche formidable, also known as the northern funnel-web spider or river or northern tree-dwelling spider, has a shiny black carapace and the rest of the body a dark brown that enables it to camouflage itself perfectly in wooded areas. Unlike other spiders, these spiders cannot jump, and when they feel threatened, they instinctively show their fangs, which are covered with venom droplets at the tip. They are like a loaded gun that will not hesitate to fire if it feels in danger.
Habitat: Their range extends up and down the east coast of Australia, and they are generally the only two species of funnel-web spider that inhabit trees. They can be found in wooded areas, incredibly highly humid. Their burrows are often found in rotting logs, fallen branches, hollow furrows and recorded in trees up to 30 metres above the ground. During the day, they are difficult to encounter, as this is when they seek refuge from natural predators. Forest beetles are their primary prey.
Medical facts: Their venom is considered the most toxic of this arachnid family, and symptoms appear 15-20 minutes after the bite. This venom is faster acting than the Sydney funnel-web spider. However, it can be effectively treated with the exact antidote. As soon as the spider bite occurs, the victim should be immobilised and pressure bandages applied around the affected area; this will delay the symptoms as much as possible and allow for greater ease of treatment.
Behaviour: Northern and southern funnel-web spiders are regularly found in trees, both in tree furrows and in rotting trunks or fallen branches, where they make their burrows and tend to be sheltered. Wandering males tend to be seen in the rainy months, mostly at night. These spiders are highly venomous and can be fatal if the spider bite is not treated with an antidote as soon as possible. When they feel threatened, they are very aggressive.
Danger: This spider is much more giant than the Sydney funnel-web spider, so the amount of venom it injects is also more significant, making it even more deadly by volume. Commonly, after a spider bite, the main symptoms are diaphoresis, hypertension (hypertensive people should be cautious, as they can end up much worse than an average person after a spider bite), sinus tachycardia, vomiting and nausea, severe pain at the site where the spider attacked, altered consciousness and even muscle spasms. Remaining calm and going to the doctor immediately is essential, and if possible, collect the spider for accurate identification of the species.
This species is native to Australia, its shape and colour are frightening enough that you don't want to encounter it, and if you do, you want to stay as far away from it as possible, even if you don't know how dangerous it is or if your life is at risk after a bite from it.
Appearance: These spiders are not Small; they are tiny! While females can grow to about 10 millimetres, males tend to be no larger than 3 or 4 millimetres. Females are entirely black or dark brown, except for a red stripe on the abdomen. On the other hand, Males are light brown and have a light-coloured hourglass-shaped marking on the underside of the stomach.
Habitat: Latrodectus hasselti or Australian red-backed spiders tend to live in urban areas. Their diminutive size allows them to burrow almost anywhere, as long as it meets specific requirements: darkness and a total lack of moisture are essential for these spiders when choosing their home. Mailboxes, wooden latrines, sheds, attics, and any dark corner inside and outside your home will be welcoming enough for these insects.
Medical facts: Males do not tend to bite people unless they feel under serious threat. Their bite will only cause weak pain in the affected area. Female redbacks, however, may be a little more aggressive, especially if they sense that their web is in danger or detect a potential predator. Their venom can cause nerve damage and nausea in their victims. If you come across one of these tiny spiders and it bites you, head immediately to a doctor for an antidote.
Behaviour: Sexual cannibalism is widespread in this species of Australian spider. In 65% of cases, the male is injured during reproduction, and at least 15% of them die after or during intercourse. Despite their size, their shiny black colour and the red stripe on their abdomen make these spiders look dangerous, even though they are tiny. However, they are not aggressive, and only females tend to bite people. Their web is lovely and quite challenging, and everything seems to indicate that the design of the web does not follow a particular pattern.
Danger: This species is not aggressive, and as mentioned above, the females tend to bite people. There are 500-1000 reported red-backed spider bites annually, and they are probably the most frequent cause of antivenom injection in the country, estimated at 300-400 times a year.
The mouse spider is not one of the most miniature spiders you will find in Australia; although it is not very big, its appearance alone inspires respect, as the last thing we want is a bite from this spider.
Appearance: The head is undoubtedly the most distinctive part of this spider, with its wide jaw would instinctively drive more than one away. Its body tends to be shiny and dark in colour, mainly black or brown, and it has short spinnerets and a broadhead. Its size varies from 1 to 3 centimetres depending on the sex of the spider and the species you encounter, as eight species of mouse spider are known to date.
Habitat: Humidity is the main characteristic that potential burrows for this species must-have. The higher the humidity, the more likely you encounter a mouse spider. Near rivers and lakes, houses in the country, next to dams, are the most common habitats for mouse spiders in Australia.
Medical facts: Given the characteristics of the mouse spider's habitat, which tends to burrow in areas of high humidity, these are often found away from more populated urban areas. As a result, the rate of mouse spider incidents is relatively low. Still, it would Help if you were wary of their bite, like any spider on our list.
Behaviour: Mouse spiders are usually solitary and generally do not tend to be wandering around but stay close to their burrows, where they feel safe. They are not aggressive but try not to make them feel threatened, as they will attack instinctively. Males are the most active, while females stay almost all year round in the burrow; these come out to hunt in the late summer to an early autumn period of the year in search of prey
Danger: The first thing you should know is that mouse spider bites are not fatal. Signs of poisoning almost always begin with fatigue, and their venom, which closely resembles that of the funnel-web spider, although less toxic, can cause some illnesses.
It was discovered and classified two years ago as a new genus of spiders. The Cryptophoris, as they were baptised, or trapdoor spiders, as they are popularly known, are a curious group of spiders. Their name "trapdoor spider" is related to the curious shape of their burrows, which at the entrance have a silken "trapdoor", from which they emerge to catch their prey when unsuspecting.
Appearance: The appearance of spiders of this species tends to vary somewhat by family, but generally, they all tend to be hairy, plump, round and bright brown (either light or dark). Depending on the specimen you come across, they can vary a bit in appearance, from the colour, which can range from light brown to practically black, to the shape of their legs: size, thickness and shape.
Habitat: A whole new species of hunting spiders has been discovered all along the east coast of Australia: the trapdoor spiders, a family within which some had been camouflaged and found mixed with other genera. The habitat of this family of spiders is divided between urban and natural areas. Whether in the forests and natural parks of Australia's east coast or urban areas, you will come across one of these little friends.
Medical facts: Their non-aggressive behaviour and venom characteristics mean that spiders in this family are not deadly. Provided that if you happen to run into them but don't disturb them, you shouldn't get hurt badly.
Behaviour: From elements found in their habitat such as branches, leaves and with their silk, trapdoor spiders create and place at the entrance of their burrows a trapdoor or door that not only keeps them safe and sheltered from predators and floods but they also use them for hunting their prey when these are clueless. Hence the aptness of the scientific name given to this family of spiders: Cryptophoris, meaning cryptic door.
Danger: The pain from a bite from one of these trapdoor spiders can last for quite a while, and the area will begin to swell. In addition to the pain and swelling, the spider's venom may cause lethargy and nausea. As always, we recommend that you go to a health centre immediately.
Occupying position #6 on our list is the lampoon cylindrical and marina, also known as the white-tailed spider. It is one of the most common species in the country and can usually be found throughout Australia.
Appearance: Spiders in this family can grow to about 4 cm at most between their bodies and the size of their legs. They are relatively small, and although they are not tiny, they would not attract much attention next to some Australian tarantulas. They are long and slender, unlike most spiders which tend to be thicker, and as usual, they are dark brown except for the lighter legs. Their name is given by the whitish tip of their abdomen, which simulates a small whitetail.
Habitat: They are one of the most common species in Australia because you can find them in virtually any habitat, both urban and rural. They are native to southern and eastern Australia and live on the ground. They do not burrow but roam in search of prey.
Medical facts: A bite from any spider will undoubtedly cause concern for the person affected and those around them. The same is true for this species, especially since it has become popular to believe its venom is aggressive. However, a bite from a white-tailed spider may only cause some pain and discomfort. If you have overly sensitive skin or are an allergic person, you could face some complications, but they won't be life-threatening.
Behaviour: Unlike the other specimens discussed in this article, these white-tailed spiders have a somewhat peculiar behaviour. Australian white-tailed spiders are considered to be nocturnal hunters. At night they are often found stalking their favourite victims: other spiders, which they actively hunt without the need to make webs but instead creep and paralyse with their venom.
Danger: If you manage to identify that you are facing an Australian white-tailed spider, try to breathe and relax, as you are not in danger, your life is not at risk, nor will you meet a fatal fate, as the venom of this spider, although believed to be necrotising, will not endanger your health. The most common symptoms range from pain and swelling in the affected area to nausea, vomiting, headache and general body discomfort.
These noisy spiders, popularly known as barking or hissing spiders due to their peculiar sounds, belong to four genera: selenocosmia, selenotholus, stenotypes and phlogiellus.
Appearance: Large fangs and even larger legs that can measure up to 16 centimetres, not to mention how thick they are; Australian tarantulas can count up to 6 centimetres long. Their brown colour (dark or pale depending on the genus) allows them to camouflage themselves very well in the areas they commonly inhabit.
Habitat: You will recognise a tarantula burrow by the amount of silk that will protrude from the hole they live in. Whether it is under fallen logs or large rocks, you can easily find them by the excess silk in their shelters and because these tend to be at ground level, as they take advantage of natural structures (logs, rocks, etc.) and reach a depth that can vary from 40 to 100 cm.
Medical data: The venom of this species is not fatal to humans, although it can be fatal to your pets, mainly dogs. Although tarantulas are generally relatively calm, there has been a considerable increase in tarantula bites reported to health centres and emergency calls. While this has been attributed to the increasing number of people keeping these animals as pets, if you live in Australia, you are not exempt from encountering one of these creatures, so try not to disturb them.
Behaviour: Although they are known as bird-eating spiders, these animals rarely form part of their diet. Instead, lizards, frogs, other insects and other spiders are usually their favourite treats. Known as hissing spiders, this peculiar sound indicates that the spider is feeling threatened, and they will accompany it with a defensive and threatening posture. Tarantulas do not tend to be an aggressive species, and if you come across one, it will let you know if it feels threatened.
Danger: While tarantula venom is not going to kill you by any means, you will feel terrible pain, mainly caused by the size of their fangs, which can be genuinely terrifying, and if you don't believe it, wait until you come across one, as they can measure up to a centimetre. In addition, their venom can leave you in a feverish state for a while and nauseous and vomiting. If you have pets at home, it is vital to make sure you don't also have tarantulas in the house, as dogs, in particular, are pretty susceptible to their venom, and a single bite can cost them their lives.
The Loxosceles reclusa or recluse spider is one of the most dangerous spider species on our list, and you should watch out for it. Its small size makes this task particularly difficult, but at least the signs of poisoning tend to be clear enough to alert you to head for the nearest health centre immediately. Here we bring you all the details you need to know about the Australian recluse spider.
Appearance: As we said earlier, the Australian recluse or recluse spider is a tiny spider, so it's pretty hard to notice it's around unless you have quite a bit of respect for insects in general and have your eagle eye on 24/7. With a slender body and long legs, recluse spiders are characterised by a white violin-shaped spot on the back, which stands out against the brown colour (light or dark depending on the spider) characteristic of their body.
Habitat: Although generally, this species of Australian spider tends to live on the ground, it is possible to find them in other places inside and outside the house and in any urban or rural area around Adelaide. Their burrows can be almost anywhere they can feel safe and have prey within reach: logs, sheds, mailboxes, ladders, rocks, etc.
Medical facts: The recluse spider, as we said at the start, is one of the most dangerous species on our list, and if it were just a couple of centimetres more prominent, it would occupy the first position at the top of the deadliest Australian spider bites; as its venom can cause necrotic wounds severe enough to worry about if they are not treated as soon as possible.
Behaviour: They prefer to make their burrows at ground level as, being hunting spiders, it is much more comfortable for them to do so, as they do not sit and wait for food to come to them literally; they are more of a foraging spider. They hunt day and night and attack when they detect that their prey is unaware. Although these spiders are generally calm, you mustn’t make them feel threatened if you come across one. Otherwise, it will have no choice but to attack you.
Danger: This spider is quite dangerous; it is not even deadly, thanks to its size. Of course, this is a double-edged sword, as it is so tiny that you may not notice it the moment it bites you, but you will begin to suspect it as soon as the symptoms appear. This makes them even more dangerous, as the venom of almost all Australian spiders causes vomiting. Still, this poison could also cause fever and skin lesions or ulcers that could become necrotic lesions that take time to heal.
If spiders already make a wrong impression on you because of their appearance, this species could give you nightmares. The Australian hunting spider, or the Australian giant hunting spider, is the spider with the longest legs globally, with legs that can reach up to 30 centimetres. Yes, exactly as you just read, 30 centimetres - creepy, isn't it? Despite occupying one of the last positions on the list, it is one of the deadliest, and its venom could kill you.
Appearance: Beyond what we have described in this spider, we can go into other details. In addition to the exaggerated size of its legs, its body can measure from 8 to 15 centimetres long, so, typically, its size will leave more than one person paralysed. They also tend to be quite hairy, and although their colours are pretty varied, they are easy to recognise by their symmetrical striped patterns and markings.
Habitat: They generally live in caves or caverns, although they have been moving throughout the territory. The expansion of urban civilisation to more isolated areas has meant that this species has had to live closely with humans. Warm, damp places are their favourite hiding places, and they can be found in any natural or urban area. Despite hunting spiders, they do not tend to be exposed to light but rather stay in dark places.
Medical data: Not too many bites are reported from this spider annually since, as we said earlier, it is much more likely that if you come across one, it will end up running away from you rather than attacking you.
Behaviour: Despite their surprising size, these spiders are pretty fast and elusive, not expected given their physical characteristics. A hunter, after all, does not use silk webs to trap its prey but neutralises them with a lethal poisoned bite and carries it back to its burrow as a backup. Their taste is fatal. However, Australian giant slayers do not usually intrude on animals larger than themselves, so before stopping to bite you, they will prefer to run away from you.
Danger: When a giant slayer bites you, you should go to a health centre as soon as possible. Afterwards, it is widespread for the affected area to remain irritated and sore. The greatest danger of this spider is undoubtedly the terrible panic it can cause, especially in sensitive people.
Their webs are undoubtedly more famous than the spiders themselves, as more than one of us has probably had to do the "crazy spider dance" on more than one occasion, trying to remove them from your face and fearing that the little spider has been resting in its web. They are one of the most common spiders in urban areas all over Australia. Removing their large webs at any given moment becomes a national sport as it is common to walk down the street and find someone complaining and cleaning up.
Appearance: Belonging to a family of over 2800 species, Australian orb-weaving spiders tend to differ in appearance. Generally speaking, the traits that do hold across the species is that the female varies in size from 2 to 3 centimetres. At the same time, the male, as is typical in spiders, tends to be smaller, from about 1.50 to 2 centimetres. Most of these weaver spiders are primarily robust and reddish-brown or grey.
Habitat: Orb-weaving spiders build flat webs, first securing a point on one surface and drifting to the next, then heading to the centre and creating a Y-shape they drop to the ground, where they finish attaching the web. They then begin to weave orb shapes. Many of the spiders in this family spend practically their entire lives in their net, day and night, and others do not spin their web at all, although this is not the most usual. You can find them everywhere: gardens, houses, forests, parks, trees, roofs, sheds, etc.
Medical Facts: It is not common for these spiders to decide to bite, but they are reluctant. They are calm spiders, and as long as you do not disturb them, they will not act aggressively. However, there have been cases of these spiders biting humans. Their venom is not lethal; although it can cause symptoms such as dizziness and vomiting, they usually remain as mild pain in the area of the bite that can evolve into swelling and, in some cases, numbness of the site.
Behaviour: Their diet consists of insects, which they catch with their large webs. Hence they usually spend a lot of time in their nets, waiting for a victim to fall into the trap to feed on. They are virtually harmless spiders; they do not attack unless they feel threatened, and usually, when they feel threatened, they tend to move away or pretend to have died. They hang upside-down, waiting for prey when they have finished their web.
Danger: These spiders tend to run away when they feel threatened, so they won't dare attack you directly unless you give them no choice. However, their fangs are pretty Small, and their venom is not lethal, so be cautious, but don't be paralysed by fear if you encounter one of these spiders. Spiders are creatures that are best given their space. They are plentiful in Australia and are a common sight everywhere.
They are also one of the most challenging pests to eradicate. Some of these little critters, mainly the species on this list, are life-threatening to humans and many other animals. If you have a spider infestation at home, do not hesitate to contact us. Try always to keep a safe distance from these spiders, and if you are bitten by one of them, it is essential that you try to identify it and that you go to the nearest health centre so that they can give you the antidote you need and calm the symptoms of poisoning that they could cause.
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