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Brazilian Wandering Spider

The Brazilian Wandering Spider (Phoneutria fera) is an aggressive and highly venomous spider . It was first discovered in Brazil hence its name. However, this genus is known to exist elsewhere in South and Central America .

The Brazilian Wandering spider is a member of the Ctenidae family of wandering spiders.

The Brazilian Wandering spider appeared in the Guinness Book of World Records 2007 for being the most venomous animal .

In this particular genus, there are five known similar species whose members are also highly venomous. They include some of the relatively few species of spiders that present a threat to human beings.

Brazilian Wandering Spider Characteristics

The Brazilian wandering spider can grow to have a leg span of up to 4 – 5 inches. They are large hairy spindly-looking spiders who have eight eyes, two of which are large. Brazilian wandering spiders are fast-moving spiders, their legs are strong and spiny and they have distinctive red jaws which they display when angered.

The Brazilian wandering spider is not a Tarantula . Brazilian wandering spiders are not even in the same family group. Tarantulas are harmless to humans and are mostly ambush killers who wait for prey to come to them. Brazilian wandering spiders are active hunters. Brazilian wandering spiders and Tarantulas do have one thing in common, however, they do not eat bananas.

Brazilian Wandering Spider Habitat and Spider Webs

The Brazilian Wandering spider is so-called because it wanders the jungle floor, rather than residing in a lair or maintaining a web. This is another reason it is considered so dangerous. In densely populated areas, the Brazilian Wandering spider will usually search for cover and dark places to hide during daytime, leading it to hide within houses, clothes, cars, boots, boxes and log piles. This usually causes accidents when people disturb them.

The Brazilian Wandering spider is also called the ‘banana spider’ as it is occasionally found within shipments of bananas. As a result, any large spider appearing in a bunch of bananas should be treated with due care.

Brazilian Wandering Spider Diet

Adult Brazilian Wandering spiders eat crickets, other large insects, small lizards and mice. Spiderlings of this species eat flightless fruit flies and pinhead crickets.

Brazilian Wandering Spider Reproduction

All spiders produce silk, a thin, strong protein strand extruded by the spider from spinnerets most commonly found on the end of the abdomen. Many species use it to trap insects in webs, although there are many species that hunt freely such as the Brazilian Wandering spider. Silk can be used to aid in climbing, form smooth walls for burrows, build egg sacs, wrap prey and temporarily hold sperm, among other applications.

Brazilian Wandering spiders reproduce by means of eggs, which are packed into silk bundles called egg sacs. The male spider must (in most cases) make a timely departure after mating to escape before the females normal predatory instincts return.

Mature male spiders have swollen bulbs on the end of their palps for this purpose and this is a useful way to identify whether the spider is male or female. Once the sperm is inside the female spider, she stores it in a chamber and only uses it during the egg-laying process, when the eggs come into contact with the male sperm for the first time and are fertilized. The Brazilian Wandering spiders life cycle is 1 – 2 years.

Brazilian Wandering Spider Venom

Bites from the Brazilian Wandering spider may result in only a couple of painful pinpricks to full-blown envenomed. In either case, people bitten by this spider or any Ctenid should seek immediate emergency treatment as the venom is possibly life threatening.

The Phoneutria fera and Phoneutria nigriventer (two species of wandering spider) are the two most commonly implicated as the most vicious and deadly of the Phoneutria spiders.

The Phoneutria not only has a potent neurotoxin, but is reported to have one of the most excruciatingly painful envenoms of all spiders due to its high concentration of serotonin. They have the most active venom of any living spiders.

One of their members, the Brazilian Huntsman, is thought to be the most venomous spider in the world. Brazilian wandering spiders are certainly dangerous and bite more people than any other spiders.

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Brazilian Wandering Spider Facts

Brazilian wandering spider profile.

There are more than 50,000 species of spider, and the vast majority are less dangerous than a honeybee. Almost none are aggressive, and of those with medically significant venom, only a small percentage are capable of causing death. So, on the whole, arachnophobes are just being a bit silly.

But there’s one spider that vindicates all of these fears, and few animals are as globally renowned to be a serious threat to human lives as the Brazilian Wandering Spider .

Brazilian Wandering Spiders are actually 9 species of spider in the same genus ‘Phoneutria’, one of which is found in Central America, with the rest in South America.

Brazilian Wandering Spider Facts

Brazilian Wandering Spider Facts Overview

These spiders are called wandering spiders because of instead of spinning a web to wait for food, or occupying a lair, they spend their night wandering in the leaf litter of the jungle floor for prey.

The sensitive hairs on its body help detect vibrations of passing prey, and it will feed on insects, lizards, frogs and any animals as large as itself.

During the day they will hide under logs, rocks, or inside termite mounds and banana plants. They will also sometimes wander into urban areas and homes, where they can come into contact with humans.

Brazilian wandering spiders are aggressive , dangerous and frightening. For once, this is an animal you should be wary of.

The females are larger, around 50% heavier than males, and produce more venom, and this might be a clue as to why their Greek name translates to “ Mudress” . These spiders will often stand and fight and have an intimidating threat display.

The potency of their venom is one of the reasons they’re so dangerous, and their ability to hide away in fruit and shoes explains why most bites are on extremities.

Interesting Brazilian Wandering Spider Facts

1. armed spiders.

In Brazilian, these are sometimes known as armed spiders, on account of their elongated front legs.

They can convey quite a bit of information with these legs, and as wandering spiders, use them to get about the forest, looking for food.

Brazilian Wandering Spider

2. Banana Spiders

They’re also sometimes called ‘banana spiders’ on account of their status as a stowaway on popular fruit imported from the tropics.

This is becoming less common as stricter regulations ensure there’s less contamination of fruits, but there’s always a chance your next bunch of bananas will have a family of these spiders living inside it.

3. They have the largest venom glands of any spider

Females produce more venom than males, but both sexes have enormous venom glands. These glands are even more impressive when you consider the size of the spider is significantly less than the largest around.

The venom glands of the Brazilian Wandering Spider are over a centimetre long, and this is all housed inside the bright red chelicerae (mouth parts) which they are quick to display whenever they get upset. 1

4. They’re aggressive

These spiders can grow quite large and have long, brightly-coloured legs. Unlike most spiders, they’re known to stand their ground when threatened and are far quicker to bite than many other species.

They’ll still try to scurry away where possible, and they’re not out to get anybody.

But where most other species will flee, the wandering spiders’ aggression does make it more likely to be involved in incidents.

Most bites are on fingers and toes, a sign that they’re being stepped on or grabbed inadvertently. When the spider feels cornered, it’ll rear up on its back legs and waves its colourful arms around as a warning.

Then it’ll sway side to side, beckoning you to have a go. Anything foolhardy enough to call this bluff gets a wealth of envenomation effects. 2 3

Brazilian Wandering Spider threat display with front legs raised

5. They give some men erections

There are ways to accomplish this with fewer side effects, but a bit from a Brazilian wandering spider does come with a certain Viagral quality.

This isn’t as fun as it might sound. Prolonged erections in this manner are likely to harm and destroy muscles and blood vessels in the penis and could cause irreparable damage.

Besides this, the assault on the central nervous system that comes with envenomation by this spider doesn’t sound worth it. 4

6. And some people die

This assault brings with it a whole host of unpleasant symptoms. Seizures, foaming at the mouth, inability to speak, collapse, and a host of other miserable experiences.

Paralysis is possible, as is cardiac shock. Blood vessels can burst in the brain, or anywhere else, and in many cases, this can be enough to kill a person.

This spider has one of the most potent venoms of all, and there are multiple legitimate records of death as a result of bites.

7. But they’re rarely fatal

While the Brazilian wandering spider is potentially one of the most dangerous spiders in the world, there is some evidence to suggest it gives a dry bite, defensively.

This means that despite exceptionally toxic venom, the amount actually injected is less than some of the other contenders, and this is what makes it typically less lethal than the Australian funnel webs.

These spiders are classified as Dangerous Wild Animals and would therefore require a special permit to keep. Bites from wandering spiders are common in South America, but antivenom is often readily available, and they rarely result in death.

In most cases, lethal bites are cases of a very young or very old victim, and few people of healthy age are killed. 5

Banana Spider

8. They do invade the UK sometimes

These unquestionably scary spiders show up in supermarkets in the UK on occasion, having hitched a ride on banana shipments.

On more than one occasion they’ve made their way into shoppers’ homes, but it doesn’t appear that there are any cases of them biting people as a result.

These spiders aren’t suited for temperate climates and don’t survive Winter, so there’s no risk of them multiplying.

Brazilian Wandering Spider Fact-File Summary

Scientific classification, fact sources & references.

  • PeerJ. (2017), “ Dimensions of venom gland of largest venom glands in all spiders ”, Bio Numbers.
  • Dave Clarke (2010), “ Venomous spider found in Waitrose shopping ‘beautiful but aggressive’” , The Guardian.
  • “ Phoneutria Perty (Arachnida: Araneae: Ctenidae) ”, UF-IFAS University of Florida
  • Kátia R.M. Leite (2012), “ Phoneutria nigriventer spider toxin Tx2-6 causes priapism and death: A histopathological investigation in mice ”, Science Direct.
  • “ Brazilian wandering spiders: Bites & other facts ”, Live Science.

What's That Bug?

Brazilian Wandering Spider Bite: Is It Poisonous? What You Need to Know

The Brazilian wandering spider, known scientifically as Phoneutria, is a genus of spiders native to South and Central America.

They have garnered attention for their venomous bite, which can cause various symptoms and has the potential to be fatal.

This article will delve into the nature of the Brazilian wandering spider’s bite and its potential effects on humans.

Brazilian wandering spiders are notorious for having one of the most venomous bites among spiders in the world.

Brazilian Wandering Spider Bite

The severity of a bite’s effects is dependent on the amount of venom injected, and in some instances, the bite might not be as harmful as anticipated.

However, it is essential to be aware of the possible symptoms and seek immediate medical attention if bitten.

Some symptoms of a Brazilian wandering spider bite may include pain at the bite site, difficulty breathing, blurred vision, and sweating.

In severe cases, the bite can also cause high blood pressure, vomiting, and even death.

Prompt treatment can help mitigate the potential harm caused by these venomous bites and prevent long-lasting health consequences.

Brazilian Wandering Spider: Overview

The Brazilian wandering spider , also known as banana spiders , can be found primarily in South America. They prefer:

  • Tropical forests
  • Subtropical areas
  • Human settlements

Physical Characteristics

Brazilian wandering spiders have the following features:

  • Size: Up to 2 inches (5 cm) in body length
  • Leg span: Can reach up to 6 inches (15 cm)
  • Hairy: Present on their legs and abdomen
  • Color: Varies from brown to black, with some species showcasing red or orange patterns

Phoneutria nigriventer is one species within this group.

Source: Pavel Kirillov from St.Petersburg, Russia, CC BY-SA 2.0, via Wikimedia Commons

Source: Pavel Kirillov from St.Petersburg, Russia ,  CC BY-SA 2.0 , via Wikimedia Commons

These spiders demonstrate unique behavior:

  • Nocturnal : They’re more active at night.
  • Aggressive : They have a defensive posture when threatened, which includes lifting their front legs.
  • Venomous : They possess a potent venom that can be dangerous to humans.

Table: Brazilian Wandering Spider vs. Common House Spider

The Venomous Bite

Venom composition.

The Brazilian wandering spider, also known as Phoneutria, contains a complex cocktail of toxins in their venom. Some of the critical components include:

  • Neurotoxins
  • Insecticidal peptides
  • Pain-inducing substances

Envenomation and Its Effects

When a Brazilian wandering spider bites, it injects venom that can lead to various symptoms such as:

  • Pain that radiates from the bite
  • Muscle cramps
  • Increased sweating

Although bites are rarely fatal, serious complications can arise when left untreated, potentially leading to death.

Comparison with Other Venomous Spiders

The Brazilian wandering spider is considered one of the deadliest spiders due to its potent venom.

However, antivenom is available for its bite, significantly reducing the risk of severe complications.

In comparison, other venomous spiders like the black widow , brown recluse , and Sydney funnel-web spider are also known for their potent venom but have varying severity of symptoms.

Source: Bernard DUPONT from FRANCE, CC BY-SA 2.0, via Wikimedia Commons

Source: Bernard DUPONT from FRANCE ,  CC BY-SA 2.0 , via Wikimedia Commons

Symptoms and Treatment of Brazilian Wandering Spider Bites

Recognizing the bite.

Recognizing the bite of the Brazilian wandering spider is crucial for seeking proper medical attention.

The main signs of a Brazilian wandering spider bite are:

  • Redness and swelling around the bite area
  • Intense pain at the bite site

Immediate and Long-term Symptoms

After being bitten by a Brazilian wandering spider, you may experience immediate and long-term symptoms.

Some common immediate symptoms include:

  • Excessive sweating
  • High blood pressure
  • Numbness, usually around the bite area

Brazilian wandering spider bite symptoms can escalate and result in more severe complications like envenomation.

Long-term symptoms can range from:

  • Muscle pain or cramping
  • Abdominal pain
  • Respiratory distress

Prevention and Safety Tips

Avoiding bites.

Brazilian wandering spiders can easily be spotted due to their large body length and venomous bite.

To avoid bites from these spiders, follow these tips:

  • Keep an eye out : Be cautious in areas where spiders are common.
  • Protective clothing : Wear long-sleeved shirts, pants, gloves, and boots when in areas with spider activity.
  • Stack materials properly : Minimize empty spaces between stacked materials to reduce hiding spots for spiders.

What to Do if Bitten

If you suspect a bite from a Brazilian wandering spider, take the following first aid steps:

  • Clean the bite area with soap and water
  • Apply a cold pack to the bite site to reduce swelling
  • Antivenom is available for Brazilian wandering spider bites
  • Proper treatment can minimize long-term effects and complications
  • Delayed treatment may worsen symptoms and lead to severe complications

Unfortunately, antivenom may not be readily available in certain regions. It is important to contact the health authorities immediately, who can help coordinate procurement of the antivenom.

It’s important to note that immediate treatment is crucial as Brazilian wandering spiders are venomous and their bites can lead to life-threatening complications.

Source: Rodrigo Tetsuo Argenton, CC BY-SA 4.0, via Wikimedia Commons

Source: Rodrigo Tetsuo Argenton ,  CC BY-SA 4.0 , via Wikimedia Commons

Frequency of Bites

While the Brazilian wandering spider is notorious for its venomous bite, actual incidents of bites on humans are relatively rare.

These spiders are nocturnal and tend to avoid populated areas during the day.

However, due to their wandering nature, they sometimes find themselves in human habitats, especially in rural or suburban areas close to their natural habitats.

Most bites occur when the spider feels threatened or cornered.

It’s worth noting that not every bite results in envenomation; sometimes, the spider delivers a “dry bite” without injecting venom.

Nevertheless, given the potential severity of a venomous bite, any encounter should be treated with caution.

Interesting Brazilian Wandering Spider Facts

Spider mating and reproduction.

The Brazilian wandering spider or armed spider , scientifically known as Phoneutria fera , is known for its unique mating and reproduction habits.

These arachnids, like other spiders, engage in an elaborate mating dance:

  • Males approach females cautiously
  • Present a gift (usually prey like crickets)
  • Perform vibrations and touches

Once successful in their ambush , males deposit sperm in a female’s reproductive organ through their specialized pedipalps.

Female Brazilian wandering spiders create silk egg sacs to protect their offspring.

These egg sacs can contain up to 1,000 eggs, ensuring the survival of the species.

Unique Uses of Spider Venom

Brazilian wandering spider venom is one of the most potent in the world . The venom has an impact on the nervous system and can cause symptoms similar to a beesting.

However, researchers have found potential uses for this venom, specifically in treating erectile dysfunction.

A peptide in the spider’s venom called Tx2-6 can cause erections.

Studies have shown that this peptide could be a potential alternative to conventional erectile dysfunction treatments.

The Brazilian wandering spider, native to South and Central America, is renowned for its potent venom, making it one of the world’s most venomous spiders.

While their bite can lead to severe symptoms, including pain, blurred vision, and even death, timely medical intervention can mitigate these effects.

Despite their fearsome reputation, these spiders play a vital role in their ecosystem.

Their unique behaviors, from nocturnal habits to intricate mating dances, make them a fascinating subject of study.

As with any venomous creature, understanding and respecting their habitat is key to coexistence.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about Brazilian wandering spiders.

Scroll down to have a look at some of them.

Letter 1 – Wandering Spider from Costa Rica

wandering spider poisonous

We believe this is one of the potentially dangerous Wandering Spiders in the family Ctenidae based on this Photographers Direct image.

Letter 2 – Wandering Spider from Costa Rica

wandering spider poisonous

Hi Reisa, Back in February 2006, we received two letters with images of spiders from Costa Rica and Ecuador. At that time, we identified them as Wandering Spiders. Eric Eaton wrote: “either in the family Ctenidae or Sparassidae.

They tend to be more common, and even larger than, wolf spiders in the tropics. At least one species, Phoneutria fera, is extremely aggressive, with potentially deadly venom.

Do not mess with large spiders in Central and South America! The venomous types are very difficult to distinguish from harmless species, and in any event, a bite is going to be really painful.

These spiders sometimes stow away in bananas, houseplants, and other exported goods, so they can show up in odd places. Be careful where you put your hands.”

We found a site with an image of Phoneutria fera, and the coloration is different, but the body shape is very similar.

Bugman

Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page .

Piyushi Dhir

Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

1 thought on “Brazilian Wandering Spider Bite: Is It Poisonous? What You Need to Know”

This is Phoneutria boliviensis – the only Phoneutria that occurs in Central America. It seems that this species is considered to be the least dangerous of its genus. All the same, I would not care to be bitten by one.

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Brazilian Wandering Spider facts

Brazilian Wandering Spider facts

Last updated on July 12th, 2023 at 01:48 pm

When you think of deadly spiders, there are a few names that spring to mind – but none more infamous than the Brazilian Wandering Spider. This species is reputed to have the most toxic venom of any spider, having a bite which causes horrendous side-effects like priapism and convulsions.

What you may not know, however, is that the Brazilian Wandering Spider name is actually used for a few species. The most common, and perhaps the most medically significant in the group are Phoneutria nigriventer and Phoneutria fera .

In this post, I’ll tell you more about these two species, from where they live, to what they eat. To keep things simple, I’ll just refer to them both as the “Brazilian Wandering Spider”, given how similar they are. Let’s dive in…

Quick Facts

To kick things off, here are some fascinating factoids about the Brazilian Wandering Spider:

  • They belong to the genus ‘Phoneutria’, which translates to ‘murderess’ in Greek.
  • They are known for their highly potent venom.
  • Wandering Spiders are nocturnal creatures.
  • They are also known as ‘banana spiders’ due to their tendency to hide in banana plants.
  • They are not web-weavers but active hunters. This is called ‘cursorial’ hunting.
  • It’s considered one of the most dangerous spiders in the world.

Other Common Names

The Brazilian Wandering Spider goes by several other names. The most common is the ‘banana spider’, thanks to their notorious habit of stowing away in banana shipments. In their native Portuguese, they’re known as ‘aranhas-armadeiras’ , translating to ‘armed spiders’ – a reference to their aggressive defense posture.

Brazilian Wandering Spider Venom

Possessing one of the most potent venoms among spiders, the Brazilian Wandering Spider’s bite is a cause for concern. Its venom is a complex cocktail of toxins, proteins, and peptides.

The main component that gets everyone’s attention is the neurotoxin, called PhTx3 , which can interfere with the functioning of our nervous system, leading to a variety of symptoms.

Brazilian Wandering Spider facts

What’s the Benefit of Having Such Strong Venom?

With venom potent enough to kill a human, one might wonder why this spider needs such a powerful weapon. The answer lies in its lifestyle.

Brazilian Wandering Spiders are active hunters and their venom is primarily used to incapacitate prey quickly. The venom’s potency also serves as an effective deterrent against potential predators.

Brazilian Wandering Spider Deaths

Despite the notorious reputation, actual deaths from Brazilian Wandering Spider bites are rare. This is largely due to the rapid medical attention available in areas where these spiders are common. Plus, these spiders don’t always inject venom when they bite – a dry bite can occur.

This actually common in venomous animals, including spiders and reptiles. Occasionally they bite and decide to not inject any venom. The point of this is to conserve it, given that it is energetically costly to produce.

Brazilian Wandering Spider Size

Being quite large and impressive compared to most arachnids, adult Brazilian Wandering Spiders can reach a leg span of up to 7 inches (18 cm) . The body size excluding the legs can be up to 2 inches (5 cm). Their size contributes to their intimidating presence.

If you’d to learn more about why they get so big, check out my article on Brazilian Wandering Spider size for more info!

Brazilian Wandering Spider Location and Habitat

Brazilian Wandering Spiders are native to South America. Here’s a quick rundown of their range and preferred habitats:

Brazilian Wandering Spider facts

Brazilian Wandering Spider Speed

An adept hunter, the Brazilian Wandering Spider can move quickly when chasing prey or evading threats. While exact speed measurements can vary, some sources report that these spiders can achieve speeds up to 1 meter per second.

What Does the Brazilian Wandering Spider Eat?

The Brazilian Wandering Spider’s diet consists mainly of insects, other spiders, and occasionally small amphibians and reptiles. Their potent venom allows them to tackle prey larger than themselves, making them one of the apex micro-predators in their habitat.

Final Thoughts…

While the Brazilian Wandering Spider might seem terrifying to many, as an arachnid enthusiast, I find them to be incredibly fascinating. Their potent venom, hunting prowess, and adaptation to diverse habitats reveal the intricate beauty of the evolutionary process.

Just remember, these spiders, like all creatures, play a vital role in our ecosystem. Respect, not fear, should be our response to these remarkable arachnids.

The truth is that most bites are accidental, but they do occur. The fact that so few deaths occur each year is a testament to the effectiveness of the antivenom that has now become widely available.

Brazilian Wandering Spider facts

FAQ related to the Brazilian Wandering Spider

What happens if you are bitten by a brazilian wandering spider.

Immediately after a bite from a Brazilian Wandering Spider, you will experience localized pain. Then, within 5 to 15 minutes the area around the bite will swell. The swelling can spread to most of a limb, for example. Finally, neurological symptoms like coldness, sweating, and convulsions will set in.

Do wandering spiders jump?

Wandering Spiders are excellent at jumping. They can jump several feet when surprised, and may occasionally use this as a tactic to evade predators. Jumping at you isn’t part of how bites happen though. When faced with humans, Wandering Spiders usually stand their ground and use their threat display of raised legs to warn us away.

Is Brazilian wandering spider friendly?

Wandering Spiders are not friendly. As a general rule, they are relatively calm, but can also be defensive. They tend to see humans as a threat, and will not take to being handled easily. That said, they are not aggressive, and most bites happen when someone accidentally touches one or tries to kill it.

Are Brazilian wandering spiders in Australia?

Brazilian Wandering Spiders are not found in Australia. The only species in Australia that get as large as Wandering Spiders are the Huntsman Spiders. At a distance they may appear relatively similar, but Huntsman Spiders are completely harmless to humans.

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wandering spider poisonous

Brazilian Wandering (Phoneutria)

The Brazilian Wandering spider is a type of spider from the Phoneutria group. Even though they’re called “Brazilian,” not all of them come from Brazil. They’re known for having strong venom. In this post, we’ll share cool facts about these spiders and help you understand them better.

Scientific Classification

  • Family: Ctenidae
  • Genus: Phoneutria

Brazilian Wandering Spider Size

List of Spiders Belonging to This Genus

Physical description and identification.

  • Size: They are large in size, with their body being 17- 48mm (.67 – 1.89 inches) long and they also have a leg span of 130 – 150 mm (5.1-5.9 inches).
  • Color: The color may vary from one species to the other, though most of them have a brown hairy body, with black spots on their stomach. Some have bright, red hairs on their mouthparts or chelicerae, while others may lack it, a feature that confuses them with species of another genus, particularly the Cupiennius.
  • Other characteristics: They often lift their body in an erect posture and hold their frontal legs high to defend themselves against predators.

Brazilian Wandering Spider Size

They are safely placed in a silken sac and the female spiders of this genus are known to lay about 1000 of them in her lifetime.

Brazilian Wandering Spider Egg

Spiderlings

They remain with their mother for some time after which they disperse to be on their own. The juvenile spiders are known to consume pin crickets as well as non-volatile fruit flies for their diet.

The spiders of this genus do not build webs but walk on the jungle floor, on the lookout for their prey.

Are Brazilian Wandering Spiders Venomous?

Yes, Brazilian Wandering Spiders have strong venom. They use it to catch their food. It’s one of the reasons they’re pretty famous.

Can Brazilian Wandering Spiders Bite?

Yes, they can bite. While they don’t always want to, they might if they feel scared or threatened by something.

Banana Spider

How Fast Can a Brazilian Wandering Spider Kill One?

It has been reported that the bite of species belonging to this genus may result in the victim’s death within one hour after the venom enters the person’s body. However, with effective anti-venom being introduced for treatment in Brazil to combat the toxic effects of these spiders, the incidence of fatalities has been less. In fact, most studies show that death mostly occurs in children below seven years of age. Of all the eight species, P. nigriventer , followed by P. fera, is said to account for most venom intoxications in Brazil.

Ecological Importance and Behavior of the Brazilian Wandering Spider

The Brazilian Wandering Spider, scientifically known as Phoneutria, stands out not just because of its reputation as one of the world’s most venomous spiders , but also due to its ecological significance and unique behavior.

Natural Predator: Despite their fearsome reputation, Brazilian Wandering Spiders are not at the top of the food chain. They fall prey to larger animals and birds. Among their predators are the coatis, certain species of large spiders, and a variety of avian predators.

Prey-Predator Dynamics: The dynamic between the Brazilian Wandering Spider and its prey is a showcase of nature’s balance. While they are efficient hunters, specializing in ambushing their prey, their own survival is constantly under threat from their predators. This cycle ensures that no one species dominates the ecosystem and that biodiversity thrives.

Relationship with Humans: The relationship between humans and the Brazilian Wandering Spider is one of respect and caution. Their venom is potent and can be harmful to humans, although fatal encounters are rare. 

Quick Facts

Brazilian Wandering Spider Picture

Did You Know

  • Species of this genus are known for wandering along the jungle floor during the night which is why they are referred to as “wandering spiders”.
  • They are alternately called “banana spiders”, a name that they also share with other species because members of this genus have often been found in banana shipments. Research in shipments going to North America showed that 7 of the 135 spiders found in such shipments were of the Phoneutria genus.
  • Phoneutria in Greek means murderess, a name perfectly attributed to its aggressive nature.

Mumpi Ghosh

Other Spiders in this Family

Wandering spiders.

Phoneutria depilata

Phoneutria depilata

Phoneutria Boliviensis

Phoneutria boliviensis

Phoneutria Fera

Phoneutria fera

Phoneutria nigriventer

Phoneutria nigriventer

Anahita punctulata

Southeastern Wandering (Anahita punctulata)

Anahita Spider

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Brazilian Wandering Spider: Size, Bite, Diet and Other Facts 

Brazilian Wandering Spider

The Brazilian Wandering Spider is a venomous arachnid with a fearsome reputation. This South American rainforest dweller packs a powerful punch, but don’t let its nickname “banana spider” fool you – they’re active hunters, not web-spinners. Despite their size and venom, bites are uncommon as they’re typically shy.

The Brazilian Wandering Spider has garnered significant attention due to its potent venom, which makes it one of the world’s most venomous spiders. Understanding its biology and behavior is crucial for both scientific research and public safety.

Scientific classification

The Brazilian Wandering Spider belongs to the family Ctenidae within the order Araneae. Its scientific classification is as follows:

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Arachnida
  • Order: Araneae
  • Family: Ctenidae
  • Genus: Phoneutria

The Brazilian Wandering Spider goes by various common names, including “armed spider,” “banana spider,” and “wandering spider.” Synonyms for this species may include Ctenus , which was formerly used for some Phoneutria species.

Distribution and habitat

Distribution:

  • South American:  Found throughout most of South America east of the Andes mountains, including countries like Brazil (their namesake), Argentina, Paraguay, and up into northern regions.
  • Central American Touch:  A few species even reach southern Central America.
  • Rainforest Dwellers:  Primarily found in the lush rainforests of South America.
  • Not Picky Places:  They can also adapt to other habitats like the Atlantic Forest and even some urban areas.
  • Daytime Hideouts:  While they wander at night, they seek shelter during the day in places like termite mounds, under rocks, or even (unintentionally) in bananas!

Physical Characteristics

 size and weight.

The Brazilian wandering spider is a creepy crawly giant. Their bodies can grow up to 2 inches (5 centimeters) long, but that’s not the scary part. Their legs can span a whopping 7 inches (18 cm), making them look even bigger. They are one of the biggest true spiders by body weight and size.

Despite their impressive leg span, Brazilian wandering spiders are relatively light. They only weigh around 6 grams, which is about the same as two pennies. While they might look imposing, they’re not the heaviest arachnids around.

Coloration and markings

These spiders exhibit a range of colors, including brown, black, and sometimes reddish hues. They often have distinctive markings on their bodies, which can vary between species. These markings may include stripes or patterns that serve as a key identification feature.

Notable features

One of the most notable features of the Brazilian Wandering Spider is its elongated, robust body and long, agile legs. They have sharp fangs, which they use to inject venom into their prey or in self-defense.

Sexual dimorphism

Sexual dimorphism is evident in this species. Females are larger and bulkier than males, while males have longer, more slender legs. Additionally, males possess specialized structures known as pedipalps, which are used during mating.

In the following sections of this article, we will delve deeper into the behavior, venom, and ecological role of the Brazilian Wandering Spider, shedding light on why this species has both fascinated and instilled fear in those who encounter it.

 Behavior and Ecology

wandering spider poisonous

 Nocturnal habits

Brazilian Wandering Spiders are primarily nocturnal creatures. They are most active during the night, venturing out of their daytime hiding places to hunt for prey and engage in mating activities. Their nighttime activity allows them to avoid predators and reduce the risk of desiccation in the hot tropical sun.

Hunting and feeding behavior

These spiders are agile hunters and primarily feed on insects, small vertebrates, and other arachnids. They do not build webs to capture prey but instead rely on their excellent senses, including acute vision and touch, to locate and stalk their victims. They often wander in search of food and are known for their swift and lethal strikes. Once they subdue their prey, they inject venom to immobilize it before feeding.

Brazilian Wandering Spiders (Phoneutria) are active hunters and have distinctive feeding behaviors. Here’s an overview of their feeding habits:

  • Active Predators: Brazilian Wandering Spiders are not web-builders like many other spider species. Instead, they are active predators. They actively roam their environment in search of prey rather than waiting for insects to stumble into a web.
  • Hunting Strategy: When hunting, these spiders use their excellent senses, including acute vision and touch, to locate potential prey. They are known for their agility and speed, which they use to stalk and capture their victims. They have sharp fangs, which they use to deliver a venomous bite to immobilize their prey.
  • Diet: Their diet consists primarily of insects and other arthropods, but they are opportunistic feeders and may consume a variety of small creatures, including small vertebrates such as frogs and lizards when the opportunity arises.
  • Venom Use: Brazilian Wandering Spiders inject venom into their prey to immobilize and partially digest it. Their venom contains neurotoxins that affect the nervous system of their victims. Once the prey is incapacitated, the spider can feed on it at its leisure.
  • Feeding Process: After subduing their prey with a venomous bite, the spider uses its chelicerae (fangs) to break down the prey’s tissues. The venom also helps in predigestion, turning the prey’s insides into a semi-liquid form that the spider can ingest. They can consume both the internal fluids and solid parts of their prey.
  • Frequency of Feeding: The frequency of feeding can vary depending on factors such as the availability of prey and the spider’s size. Generally, they need to feed periodically to sustain their energy and growth. Spiderlings may require more frequent meals to support their rapid growth, while adults can go longer periods between meals.

Overall, the Brazilian Wandering Spider’s feeding strategy is well-suited for their active and wandering lifestyle, allowing them to efficiently capture and consume a variety of prey in their natural habitat.

Role in the ecosystem

The Brazilian Wandering Spider plays a vital role in controlling insect populations within its habitat. By preying on a variety of insects and other small creatures, they help maintain ecological balance. Additionally, their presence in the rainforest ecosystem contributes to the overall biodiversity and food web.

Mating and reproduction

Mating in Brazilian Wandering Spiders is a complex and potentially dangerous process. Male spiders must carefully approach and court a receptive female to avoid being mistaken for prey. They use specialized pedipalps to transfer sperm to the female’s reproductive organs. After successful mating, females lay egg sacs containing hundreds of eggs. They guard these sacs and ensure the survival of their offspring until they hatch.

 Lifespan and growth

The lifespan of Brazilian Wandering Spiders varies between males and females. Males generally have a shorter lifespan, typically living for a few months to a year after reaching maturity. Females, on the other hand, can live for several years. The growth of these spiders involves a series of molts, during which they shed their exoskeletons to accommodate their increasing size. Molting is a vulnerable period in their lives as their new exoskeleton is initially soft and requires time to harden.

Venom and Envenomation

Composition of venom.

The venom of Brazilian Wandering Spiders is a complex mixture of neurotoxins, cytotoxins, and other enzymes. One of the most significant components is a neurotoxin called PhTx3, which targets the nervous system of their prey.

Toxicity and effects on humans

The venom of these spiders is highly potent and can be lethal to their prey. In humans, envenomation can cause a range of symptoms, including intense pain, muscle cramps, fever, nausea, and in severe cases, paralysis and death. It’s important to note that while their venom is potent, actual fatalities from Brazilian Wandering Spider bites are rare due to the availability of medical treatment.

First aid and medical treatment

In the event of a Brazilian Wandering Spider bite, immediate medical attention is crucial. First aid measures may include cleaning the wound and applying ice to reduce pain and swelling. However, the primary treatment involves antivenom, which can counteract the effects of the spider’s venom.

Cases of envenomation and fatalities

Although fatalities from Brazilian Wandering Spider bites are uncommon, there have been documented cases of severe envenomation, especially in regions where medical treatment is not readily available. These spiders are generally non-aggressive and will bite humans only in self-defense when provoked, or if they feel cornered.

Understanding the behavior, ecology, and venomous nature of the Brazilian Wandering Spider is crucial for both scientific research and public awareness, helping to minimize the risk of envenomation and promote coexistence with this remarkable but potentially dangerous arachnid.

Brazilian wandering spider life cycle

The Brazilian wandering spider has a fascinating life cycle that revolves around hunting and motherhood. Here’s a breakdown:

  • Egg Haven:  After mating, the female lays hundreds, sometimes even a thousand, eggs in a silken sac. This becomes their protected nursery.
  • Tiny Terrors:  Hatching from the eggs emerge translucent spiderlings called larvae.
  • Nymph Stage:  The larvae molt a few times, transforming into nymphs. Think of them as mini-adults but without the ability to reproduce yet.
  • Shedding for Size:  As nymphs grow, they undergo multiple molts, shedding their outer shell to accommodate their larger bodies.
  • Ready to Roam:  After the final molt, the spider emerges as a full-fledged adult, complete with reproductive organs. Now, they can join the wandering lifestyle and continue the cycle.

The life cycle begins when a female Brazilian Wandering Spider lays her eggs. She typically creates an egg sac made of silk and deposits it in a concealed location, such as a tree hollow or leaf litter. Inside the sac, she may lay hundreds of eggs. The female guards the egg sac and ensures its protection until the spiderlings hatch. The duration of the egg stage varies depending on environmental conditions but generally lasts for a few weeks.

Spiderling Stage

After the incubation period, spiderlings (young spiders) emerge from the egg sac. They are extremely vulnerable at this stage and rely on their mother’s protection and guidance. Spiderlings are miniature versions of adult spiders but lack the full coloration and size. They disperse from the nest once they have molted and are capable of hunting on their own. During this stage, they grow rapidly by molting, shedding their exoskeletons to accommodate their increasing size.

Juvenile Stage

As spiderlings continue to molt and grow, they progress into the juvenile stage. During this phase, their coloration becomes more distinct, and they start to develop the characteristic features of adult Brazilian Wandering Spiders. They become increasingly independent and begin to exhibit hunting behaviors. The duration of the juvenile stage can vary but often lasts several months.

Sub-Adult Stage

The sub-adult stage is an intermediate phase between juvenile and adult. At this point, the spiders are closer in size and appearance to adults but have not yet reached sexual maturity. They continue to molt, with the frequency of molting gradually decreasing as they approach adulthood. Sub-adult spiders may exhibit more territorial behaviors as they compete for resources and prepare for eventual mating.

Adult Stage

Upon reaching sexual maturity, Brazilian Wandering Spiders enter the adult stage. This is when they are fully developed and capable of reproduction. Females are larger and bulkier than males, and males possess specialized structures called pedipalps, which they use during mating. Adult spiders engage in mating activities, and females lay eggs to continue the life cycle. Adult Brazilian Wandering Spiders can live for several years, with females typically having longer lifespans than males.

Understanding the life cycle of these spiders is essential for studying their behavior, reproductive biology, and population dynamics. It also provides insights into their adaptation strategies in the complex ecosystems of South and Central America.

Brazilian Wandering Spider Bite

Brazilian Wandering Spider Bites

Brazilian Wandering Spiders are known for their potent venom and, occasionally, their bites on humans. While bites are relatively rare due to the spider’s non-aggressive nature, understanding the consequences of a bite is crucial for public safety.

Studying Brazilian Wandering Spider bites is of great interest for several reasons. It helps healthcare professionals provide appropriate medical treatment, raises awareness among communities in spider habitats, and contributes to our understanding of venomous arachnid envenomations.

The venom of Brazilian Wandering Spiders is a complex mixture of neurotoxins, cytotoxins, and enzymes. It contains various components, including PhTx3, which is a potent neurotoxin affecting the nervous system.

Brazilian Wandering Spider bites can have a range of effects on the human body, including intense pain, muscle cramps, fever, nausea, and in severe cases, paralysis. The severity of the symptoms depends on factors such as the amount of venom injected and the individual’s sensitivity to the venom. There are several types of spider bites .

Symptoms of a Brazilian Wandering Spider Bite

Local symptoms

  • Intense pain
  • Itching or burning sensation
  • Formation of blisters or lesions

Systemic symptoms

  • Muscle cramps and spasms
  • Abdominal pain
  • Nausea and vomiting
  • Elevated heart rate
  • Hypertension (high blood pressure)
  • Respiratory distress

Severity and variations

The severity of Brazilian Wandering Spider bite symptoms can vary widely. In some cases, symptoms may be mild and resolve on their own, while in severe envenomations, life-threatening complications can occur. Individual reactions to the venom can also vary, making it challenging to predict the exact outcome of a bite.

First Aid and Immediate Response

Steps to take after a bite

Immediate response to a Brazilian Wandering Spider bite should include:

  • – Washing the bite area with soap and water.
  • – Applying a clean, cool compress to reduce pain and swelling.
  • – Immobilizing the affected limb or area.
  • – Keeping the bite victim calm to prevent an elevated heart rate.

Do’s and don’ts in case of a bite

  • – Seek medical attention promptly.
  • – Take note of the spider’s appearance (if possible) to aid identification.
  • – Keep the bite victim still and calm to reduce the spread of venom.
  • – Do not try to suck out venom or make incisions at the bite site.
  • – Avoid applying tourniquets.
  • – Don’t use ice directly on the skin as it can worsen tissue damage.

Seeking medical attention

Medical attention is essential after a Brazilian Wandering Spider bite, even if symptoms appear mild initially. Antivenom is available and can be administered to counteract the effects of the venom. Medical professionals can also manage symptoms and monitor for potential complications.

Complications and Long-Term Effects

Potential complications

Complications from Brazilian Wandering Spider bites can include:

  • – Severe muscle spasms
  • – Respiratory distress
  • – Cardiovascular issues
  • – Kidney failure (rare)
  • – Allergic reactions to antivenom

Long-term consequences

Long-term consequences of a bite can vary depending on the severity and medical treatment received. Some individuals may experience lingering pain, muscle weakness, or psychological trauma following a severe envenomation.

Recovery and rehabilitation

Recovery from a Brazilian Wandering Spider bite typically involves medical treatment, rehabilitation for muscle and nerve damage, and psychological support for individuals affected by the experience. Rehabilitation may include physical therapy to regain muscle strength and function. Prompt medical attention and appropriate care are crucial for minimizing long-term effects and complications.

Facts of Brazilian Wanding Spider

Here are 10 creepy crawly facts about the Brazilian Wandering Spider:

  • Big and Hairy:  These spiders are giants! Their bodies can grow up to 2 inches (5 centimeters) long, with a leg span of up to 7 inches (18 cm). They are covered in hairs, making them appear even bigger.
  • Wanderlust:  They are aptly named – Brazilian wandering spiders don’t spin webs. Instead, they wander the forest floor at night in search of prey.
  • Venomous Bite:  Their venom is considered one of the most potent among spiders. A bite can cause severe pain, swelling, sweating, nausea, and even priapism in males. Thankfully, bites are rare as they are typically shy and defensive.
  • Not So Fond of Bananas:  While sometimes called ‘banana spiders,’ they are not typically found in bananas. They might, however, take shelter in them during transport, which is how they might end up in a faraway land.
  • Rainforest Resident:  These spiders are native to the rainforests of South America, particularly in Brazil.
  • Fearsome Feasters:  They’re active hunters and will eat almost anything they can overpower, including insects, lizards, frogs, and even small rodents.
  • Mom’s the Word:  Female Brazilian wandering spiders are dedicated mothers. They lay hundreds of eggs in a silken sac and fiercely guard them until they hatch.
  • Multiple Molts:  Like all spiders, Brazilian wandering spiders grow through molting. They shed their exoskeleton multiple times as they grow into adults.
  • Mating Dance:  Male Brazilian wandering spiders perform a elaborate mating dance to attract a female.
  • Medicinal Potential:  Despite their scary reputation, the venom of the Brazilian wandering spider is being studied for its potential use in treating erectile dysfunction.

What happens if a Brazilian Wandering Spider bites a man?

A Brazilian Wandering Spider bite on a man can cause a range of symptoms, some severe:

  • Pain:  The bite is known for causing intense, localized pain at the site.
  • Autonomic effects:  Sweating, nausea, and increased heart rate are common.
  • Priapism:  In some cases, males may experience a prolonged and painful erection (priapism). This is due to a component in the venom.
  • Muscle paralysis:  Severe bites can lead to muscle paralysis, which can affect breathing in rare cases.

However, it’s important to remember:

  • Bites are uncommon as these spiders are typically shy and defensive.
  • Antivenom is available and effective in treating bites.

If bitten, seek medical attention immediately. Early treatment can help prevent complications and ensure a full recovery.

How poisonous is a Brazilian Wandering Spider?

Brazilian Wandering Spider packs a nasty venomous punch, considered one of the strongest among spiders. Bites are rare though, as they’re shy and prefer to escape trouble.

What is the world’s deadliest spider?

The term “deadliest” can be subjective and depends on how one defines it (e.g., based on venom potency or human fatalities). However, the Brazilian Wandering Spider (Phoneutria) is often considered one of the most venomous spiders in the world. Another spider often mentioned in discussions of venom toxicity is the Sydney Funnel-web Spider (Atrax robustus and Atrax formosus), found in Australia. These spiders are known for their potent venom and have caused fatalities in the past.

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7 Facts About The Brazilian Wandering Spider Living in Florida has its perks—sunshine, beautiful beaches, and a tropical atmosphere. However, it also comes with its fair share of surprises. Recently, I had an unexpected visitor in my home that sent shivers down my spine—a Brazilian Wandering Spider. As I navigated through this unnerving encounter, I delved into understanding this intriguing arachnid and unearthed seven fascinating facts about the Brazilian Wandering Spider. Unexpected Visitor: Imagine my surprise when, living in sunny Florida, I found myself face to face with a Brazilian Wandering Spider. This eight-legged visitor wasn't your typical household spider—it was a creature straight out of a wildlife documentary. With a leg span that seemed to stretch for miles and those unmistakable red fangs, it was a sight that sent shivers down my spine. Intimidating Fangs: The first thing that caught my eye were those red chelicerae, poised and ready for action on its abdomen. It was like a warning sign that I had an unwelcome guest in my home. I couldn't help but marvel at the sheer size and agility of this arachnid as it gracefully moved along the walls of my living room. Venomous Trepidation: As I observed from a safe distance, the realization hit me—the Brazilian Wandering Spider is known for its venomous bite. The mere thought of those potent neurotoxins coursing through my veins was enough to send a chill down my spine. I quickly decided that this was not a creature to be dealt with lightly. No Webs, Just Wanderers: Unlike the common house spiders that spin intricate webs in corners, this spider was a wanderer. True to its name, the Brazilian Wandering Spider doesn't bother with the whole web-building routine. Instead, it actively roams around, and that's probably how it ended up in my living room in the first place. Aggressive Standoff: As I mustered the courage to guide it out of the house, I was met with an unexpected display of aggression. The spider raised its front legs, showcasing those fearsome fangs, and warned me not to underestimate its capabilities. It was a standoff between a curious human and a defensive arachnid. Out-of-Place in Florida: Living in Florida, encountering exotic wildlife isn't unheard of, but a Brazilian Wandering Spider was certainly unexpected. These creatures are native to the rainforests of South America, so how did one end up in my Sunshine State abode? The mystery behind their presence outside their natural habitat adds an extra layer of intrigue to the encounter. Maternal Instincts: As I cautiously observed the spider, I couldn't help but wonder about its life cycle. Learning that the females exhibit maternal care by creating silk sacs to protect their eggs was both surprising and fascinating. It added a touch of complexity to this creature that, moments ago, I saw as nothing more than a potential threat. My Personal Encounter It was a typical evening in my Florida home when I stumbled upon this eight-legged visitor. Startled, I cautiously observed its intricate movements as it traversed the walls of my living room. The distinctive red fangs immediately caught my attention, triggering a mix of fascination and concern. Unsure of how to handle the situation, I decided to document the encounter and seek professional assistance. Aggressive Defensive Posture When confronted, the Brazilian Wandering Spider doesn't shy away from displaying its aggressive defensive posture. My attempt to gently guide it out of the house was met with an intimidating display—raised front legs, exposing those red fangs, and a readiness to strike if I posed a threat. It was a reminder of the potential danger these spiders pose and the importance of handling them with care. Reproduction and Maternal Care One surprising fact about the Brazilian Wandering Spider is its unique approach to reproduction. The female constructs a silk sac to protect her eggs and carries it with her. Unlike many spider species, the mother doesn't abandon her eggs but actively guards and cares for them. Witnessing this maternal instinct adds a layer of complexity to the creature that goes beyond its fearsome reputation. Importance of Professional Assistance Given the potential dangers associated with the Brazilian Wandering Spider, seeking professional assistance is crucial when encountering one in your home. I promptly contacted local pest control services that specialize in handling venomous spiders. Their expertise ensured the spider was safely removed without posing a threat to me or my household. Conclusion Encountering a Brazilian Wandering Spider in my Florida home was undoubtedly an unexpected and nerve-wracking experience. However, it opened the door to a deeper understanding of these fascinating arachnids. From their distinctive appearance to the potent venom they carry, the Brazilian Wandering Spider remains a creature worthy of both caution and appreciation. As I bid farewell to my unexpected guest, I couldn't help but marvel at the intricate world of nature that often finds its way into our daily lives, even in the most unexpected places.

7 Facts About The Brazilian Wandering Spider

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Brazilian Wandering Spider

wandering spider poisonous

Brazilian Wandering Spider , scientifically known as Phoneutria, emerges as a captivating enigma in the realm of arachnids.

Renowned for its formidable reputation as one of the world’s most venomous spiders , Phoneutria embodies a plethora of intriguing traits that have captured the curiosity of enthusiasts and researchers alike.

From its distinctive appearance and neurotoxic venom to its nomadic hunting strategies and unique mating behaviors , this remarkable spider species holds a wealth of fascinating secrets waiting to be unraveled.

Join us as we embark on a journey to explore the captivating world of the Brazilian Wandering Spider, shedding light on its captivating characteristics and dispelling myths that have shrouded its true nature.

1. Taxonomy and Distribution of the Brazilian Wandering Spider

A. scientific classification of phoneutria.

The Brazilian Wandering Spider, scientifically referred to as Phoneutria, occupies a distinct place within the arachnid taxonomy.

Brazilian Wandering Spider-AnimalBehaviorCorner

Belonging to the family Ctenidae, this spider genus is further categorized into several species, each boasting unique traits and behaviors .

Phoneutria’s taxonomic position not only distinguishes it from its arachnid counterparts but also underscores its intriguing evolutionary journey.

B. Native Habitat in South and Central America

Endemic to the lush landscapes of South and Central America, the Brazilian Wandering Spider finds its natural haven within these diverse regions.

From the rainforests of the Amazon to the tropical stretches of the Caribbean, Phoneutria has adapted to a range of environments over the course of its evolution.

The spider’s ancestral ties to these regions are tightly woven into their behaviors , anatomy, and survival strategies.

C. Preference for Tropical Rainforests and Urban Areas

Within its native territories, the Brazilian Wandering Spider exhibits remarkable versatility in its chosen habitats.

While it thrives amidst the vibrant biodiversity of tropical rainforests, it has also displayed a propensity for urban locales.

Brazilian Wandering Spider-AnimalBehaviorCorner

Phoneutria’s adaptability has led it to establish a presence in urban areas, where it often finds shelter in crevices, gardens, and even human dwellings.

This adaptability to both wild and urban spaces further showcases the spider’s resilience and capacity to thrive in varying conditions.

2. Physical Characteristics of the Brazilian Wandering Spider

A. size, coloration, and distinctive markings.

The Brazilian Wandering Spider , a creature of remarkable visual intrigue, boasts an array of captivating physical attributes.

Ranging in size from a few centimeters to several inches, Phoneutria showcases a size diversity that reflects the breadth of its genus.

Its coloration varies across species, encompassing shades of brown, black, and gray, often accompanied by intricate patterns and markings that adorn its exoskeleton.

These unique markings serve not only as a visual spectacle but also as essential components of its survival toolkit.

B. Camouflage and Defense Mechanisms

The Brazilian Wandering Spider’s appearance is a masterpiece of evolution, meticulously crafted to ensure both survival and predation .

Brazilian Wandering Spider-AnimalBehaviorCorner

Its coloration and markings are tailor-made for blending seamlessly into its surroundings, granting it a potent advantage in ambushing prey and evading predators . Moreover, these markings also play a role in its defense mechanisms.

When threatened, Phoneutria adopts a defensive posture, raising its front legs and revealing its striking markings, a visual warning to potential threats. This dual-purpose camouflage and defense strategy exemplify nature’s ingenuity at its finest.

C. Sexual Dimorphism: Unveiling Gender Differences

A fascinating facet of the Brazilian Wandering Spider lies in the realm of sexual dimorphism , where gender-based variations manifest in pronounced ways.

Females tend to be larger and more robust than their male counterparts, showcasing a size disparity that has evolved in tandem with their roles in reproduction and hunting .

Beyond size, other characteristics, such as leg structure and coloration, also exhibit subtle differences between male and female Phoneutria specimens.

This divergence in physical traits adds depth to our understanding of the species’ intricate biology and behavior .

In exploring the physical characteristics of the Brazilian Wandering Spider , we uncover a canvas painted with size diversity, intricate coloration, and unique markings.

These features, finely tuned by evolution, contribute to its prowess in camouflage and defense, while the fascinating interplay of sexual dimorphism further enriches our perception of this captivating arachnid species .

3. Venomous Nature of the Brazilian Wandering Spider

A. potent neurotoxic venom: a silent lethal weapon.

The Brazilian Wandering Spider, known scientifically as Phoneutria, harbors a venomous arsenal that stands as a testament to nature’s intricate design.

Brazilian Wandering Spider-AnimalBehaviorCorner

This spider’s venom contains a potent concoction of neurotoxic compounds, tailored by evolution to incapacitate its prey swiftly and efficiently.

The neurotoxins interfere with nerve cell communication, leading to paralysis and ensuring that Phoneutria’s quarry is rendered immobile and defenseless, setting the stage for a successful meal.

B. Effects on Prey and Human Hazard

When a victim succumbs to the Brazilian Wandering Spider’s venom , the effects are a symphony of paralysis and predation .

The venom’s impact on the prey’s nervous system results in swift immobilization, offering the spider a decisive advantage in subduing its catch.

While this venomous efficiency is well-adapted for predation, it also underscores the potential danger to humans.

A bite from Phoneutria can lead to a series of neurotoxic reactions, with varying degrees of severity depending on factors such as the individual’s age and overall health.

While human envenomations are relatively rare, they can result in a range of symptoms, from localized pain and swelling to more severe neurological effects.

C. Recorded Cases of Envenomations: Unraveling the Symptoms

Throughout history, documented cases of Phoneutria envenomations have offered insights into the spider’s potential threat to humans .

Brazilian Wandering Spider-AnimalBehaviorCorner

Symptoms typically include intense pain at the bite site, accompanied by swelling and redness . In some instances, victims have reported systemic reactions, such as muscle cramps, elevated heart rate, and even breathing difficulties.

Swift medical attention and the administration of antivenom have proven effective in mitigating the severity of these symptoms.

These cases serve as a reminder of the delicate balance between the Brazilian Wandering Spider’s potent venom and the potential risks it poses to those who unwittingly encounter it.

4. Hunting and Diet of the Brazilian Wandering Spider

A. hunting techniques and wandering behavior.

The Brazilian Wandering Spider, scientifically known as Phoneutria, unveils a mesmerizing repertoire of hunting techniques that set it apart as a master predator .

Displaying an agile and nomadic behavior , Phoneutria does not confine itself to the confines of a web. Instead, it actively prowls its surroundings, tirelessly searching for potential prey.

This dynamic wandering behavior ensures that its chances of encountering a variety of food sources are maximized, showcasing a strategic approach to sustenance.

B. Active Hunting Triumphs Over Web-Building

Unlike its web-weaving counterparts, the Brazilian Wandering Spider relies on a more hands-on approach to securing its next meal.

While weaving webs might seem an efficient method, Phoneutria’s active hunting strategy offers a distinct advantage in versatility.

By forgoing the constraints of a stationary web, it can tailor its approach to suit different environments and prey types, adapting its tactics on the fly.

This adaptability demonstrates the spider’s remarkable ability to adjust its methods for optimal results.

C. Diverse Prey Spectrum: Insects to Small Vertebrates

Phoneutria’s diet is a testament to its prowess as an opportunistic predator . Its menu spans a diverse range of creatures, from insects like crickets and cockroaches to small vertebrates such as lizards and frogs , and even small rodents.

Brazilian Wandering Spider-AnimalBehaviorCorner

This wide-ranging palate highlights its ecological significance in controlling various populations within its habitat.

By consuming creatures both large and small, Phoneutria ensures a balanced ecosystem, playing a crucial role in maintaining biodiversity and ecological equilibrium.

5. Mating and Reproduction of the Brazilian Wandering Spider

A. courtship rituals and behaviors: a complex affair.

The Brazilian Wandering Spider, scientifically referred to as Phoneutria, reveals a captivating array of courtship rituals and behaviors that form the cornerstone of its reproductive cycle.

Courtship among these arachnids is a complex affair, involving intricate dances and displays that serve as both communication and assessment.

Male Phoneutria employs a combination of visual cues, vibrations, and tactile interactions to court potential mates.

This elaborate courtship process highlights the significance of precise communication in the delicate dance of reproduction .

B. Cannibalistic Tendencies: A Post-Mating Phenomenon

An aspect that sets Phoneutria’s mating process apart is the notorious cannibalistic tendency exhibited by females after mating.

Following successful mating, females may exhibit an inclination to consume their partners. This seemingly counterintuitive behavior has evolutionary underpinnings.

It is believed that this cannibalistic act not only provides the female with a much-needed nutritional boost but also eliminates potential competitors and safeguards the male’s investment in the next generation.

This intriguing behavior sheds light on the complexities of reproductive strategies within the species.

C. The Unique Mating Plug Phenomenon: A Puzzling Enigma

A distinctive feature in Phoneutria’s reproductive saga is the enigmatic mating plug phenomenon. After mating, male Phoneutria deposit a specialized substance that forms a plug within the female’s reproductive tract.

This plug is believed to serve multiple purposes. It may prevent other males from mating with the female, thus ensuring the successful transmission of the mating male’s genetic material.

Additionally, it might aid in sealing off the female’s reproductive tract, potentially protecting her from external pathogens.

This phenomenon underscores the intricate interplay of biological strategies that contribute to the species’ reproductive success.

6. Human Interaction and Urban Legends of the Brazilian Wandering Spider

A. occasional presence in urban areas: nature in our midst.

The Brazilian Wandering Spider, scientifically known as Phoneutria, has carved a niche for itself not only in the wild but also in the fabric of urban environments.

Brazilian Wandering Spider-AnimalBehaviorCorner

While its primary habitats are the lush landscapes of South and Central America, Phoneutria occasionally ventures into human -inhabited spaces. Its adaptability allows it to find shelter in gardens, crevices, and even within homes.

This coexistence with humans adds an intriguing dimension to our encounters with this enigmatic arachnid .

B. Debunking Misconceptions: Separating Fact from Fiction

The presence of the Brazilian Wandering Spider has sparked a plethora of misconceptions and exaggerated tales, contributing to the creation of urban legends.

Stories of spiders leaping from banana bunches or hiding under toilet seats have become part of modern folklore, often fueled by sensationalism.

It’s crucial to sift through these tales and recognize that while Phoneutria’s venom is potent, the likelihood of encountering a dangerous encounter is relatively low.

Separating fact from fiction empowers individuals to approach these creatures with accurate knowledge.

C. Importance of Proper Education: Identifying Friend from Foe

Education plays a pivotal role in fostering a harmonious coexistence between humans and the Brazilian Wandering Spider .

Learning to identify and understand the behaviors of Phoneutria species enhances safety for both humans and the spiders themselves.

Instead of succumbing to unwarranted fear, individuals can take steps to reduce the chances of accidental encounters and, if necessary, engage in responsible removal methods.

By arming themselves with knowledge, individuals can navigate encounters with urban-dwelling Phoneutria specimens with confidence and respect.

7. Brazilian Wandering Spider Conservation and Misunderstanding

A. significance of phoneutria in ecosystem dynamics.

The Brazilian Wandering Spider , scientifically termed Phoneutria, assumes a pivotal role within its ecosystem, contributing to a delicate balance of populations and interactions.

Brazilian Wandering Spider-AnimalBehaviorCorner

As a top-tier predator , it plays a crucial part in controlling insect and small vertebrate populations, preventing unchecked growth that could disrupt the ecosystem’s equilibrium.

By maintaining these population dynamics, Phoneutria ensures the health and stability of its habitat, highlighting its significance beyond its ominous reputation.

B. Impact of Fear and Misunderstanding: Hindrances to Conservation

Despite its ecological contributions, the Brazilian Wandering Spider often falls victim to fear-driven misconceptions that negatively impact conservation efforts.

Misunderstandings surrounding its behavior and potential danger can lead to unwarranted extermination campaigns and habitat destruction.

Fear-driven reactions not only disrupt the natural balance but also hinder opportunities to study and appreciate the species for its ecological significance.

Addressing these misconceptions is crucial to ensuring the spider’s survival and maintaining the health of its ecosystems.

C. Efforts to Dispel Myths and Promote Coexistence

Efforts to conserve the Brazilian Wandering Spider are interwoven with endeavors to educate and dispel myths.

By providing accurate information and dispelling exaggerated tales, conservationists aim to reshape public perception.

Collaborative initiatives emphasize coexistence, highlighting the importance of responsible behavior when encountering Phoneutria.

Educating communities about the spider’s role, behavior, and conservation status fosters an environment where fear gives way to appreciation, and where balanced cohabitation becomes a reality.

8. Research and Medical Significance of the Brazilian Wandering Spider

A. ongoing scientific research on phoneutria venom.

The Brazilian Wandering Spider , Phoneutria, has garnered significant attention from the scientific community due to the unique properties of its venom.

Ongoing research delves into the intricate composition of the venom, aiming to unlock its mysteries and potential applications in various fields.

The diverse array of compounds within the venom, particularly its neurotoxic components, has attracted interest for their potential medical and therapeutic implications.

B. Antivenom Development and Therapeutic Prospects

One of the most promising areas of research surrounding Phoneutria lies in the development of antivenoms and therapeutic agents.

Brazilian Wandering Spider-AnimalBehaviorCorner

The venom’s potent neurotoxic effects on the nervous system have spurred efforts to create targeted treatments for conditions such as chronic pain and neurological disorders .

Additionally, the potential for antivenoms holds promise in mitigating the effects of envenomations, offering a lifeline for individuals who encounter these spiders .

This focus on harnessing the venom’s properties for positive medical outcomes highlights the transformative potential within this enigmatic arachnid .

C. Balanced Perspectives: Navigating Ethical and Scientific Endeavors

While research on the Brazilian Wandering Spider’s venom offers tremendous potential, it necessitates a balanced perspective.

As researchers probe the venom’s properties, ethical considerations arise, including the well-being of the spiders and their ecosystems.

A holistic approach acknowledges the value of understanding Phoneutria’s natural behaviors and conserving its habitats.

This balanced perspective extends to utilizing the venom’s potential responsibly, ensuring that breakthroughs are achieved while respecting the complex interplay of science and nature.

9. Frequently Asked Questions about the Brazilian Wandering Spider

What is the brazilian wandering spider.

The Brazilian Wandering Spider , scientifically known as Phoneutria, is a venomous arachnid found in South and Central America. It’s notorious for its potent venom and is considered one of the most venomous spiders in the world.

Is the Brazilian Wandering Spider dangerous to humans?

Yes, the Brazilian Wandering Spider’s venom contains potent neurotoxins that can cause a range of symptoms in humans , from localized pain and swelling to more severe reactions. While bites are relatively rare, it’s advisable to exercise caution when encountering these spiders.

What is the spider’s habitat?

The Brazilian Wandering Spider is native to tropical rainforests of South and Central America. However, it’s adaptable and can also be found in urban areas, such as gardens and houses.

How does the Brazilian Wandering Spider hunt?

Unlike many spiders that build webs, Phoneutria is an active hunter. It roams its environment in search of prey, relying on its keen senses to detect vibrations and movements.

Are Brazilian Wandering Spiders aggressive toward humans?

Brazilian Wandering Spiders are not naturally aggressive towards humans and will typically only bite in self-defense. However, caution is advised, especially in areas where these spiders are known to inhabit.

Can the Brazilian Wandering Spider’s venom be used for medical purposes?

Yes, research is ongoing into the potential medical applications of Phoneutria’s venom. Its neurotoxic properties have sparked interest in pain management and neurological treatments.

Is the spider’s reputation for crawling into banana shipments true?

While there have been stories of Brazilian Wandering Spiders being found in shipments of bananas, these occurrences are extremely rare. Spiders are unlikely to survive the conditions of shipping and storage.

How can I stay safe around Brazilian Wandering Spiders?

To stay safe, it’s important to be cautious when encountering spiders in their natural habitat. Avoid provoking or handling them, especially if you’re unsure of their identity. If you suspect you’ve been bitten, seek medical attention promptly.

Are there any efforts to conserve the Brazilian Wandering Spider?

Conservation efforts for the Brazilian Wandering Spider are intertwined with public education and dispelling myths. Recognizing its role in ecosystems and promoting coexistence are essential steps in preserving this unique species.

What can I do if I find a Brazilian Wandering Spider in my home?

If you encounter a Brazilian Wandering Spider in your home, it’s advisable to contact local pest control professionals who can safely remove the spider without causing harm.

In the intricate tapestry of nature, the Brazilian Wandering Spider , Phoneutria, emerges as a creature of both fascination and caution.

Its venomous nature and captivating behaviors have earned it a place among the most enigmatic arachnids .

As we continue to explore its world, debunk myths, and understand its vital role in ecosystems, we find a delicate balance between awe and respect.

Armed with knowledge, we navigate the realm of Phoneutria, appreciating its complexity while fostering coexistence, a testament to the intricate dance between humans and the natural world.

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wandering spider poisonous

Brazilian Wandering Spider

The Brazilian Wandering Spider (Phoneutria fera) is a teardrop-shaped arachnid with a brown coloration. Known for its potent venom, it thrives in both the lush rainforests and human dwellings of Brazil. Its notorious wandering behavior makes it a significant presence in its habitats.

Brazilian Wandering Spider (Phoneutria fera)

Fascinating Facts about Brazilian Wandering Spider

Here are 3 interesting facts about Brazilian Wandering Spider:

  • The Brazilian Wandering Spider is considered the world's most venomous spider by the Guinness World Records.
  • They are known as 'wandering' spiders because they roam the jungle floor at night instead of residing in a lair or web.
  • Despite their notorious reputation, their bites rarely cause death in humans due to the small amount of venom they inject.

Taxonomy and Classification

Here is the scientific categorization of Brazilian Wandering Spider, providing a glimpse of their position in the biological hierarchy:

Lifecycle and Growth

Brazilian Wandering Spider's life is a journey of transformation - an adventure marked by the following captivating stages:

Egg → Spiderling → Adult

The Brazilian Wandering Spider, primarily found in the rainforest, exhibits a lifecycle that spans both wilderness and human habitats. From egg to adult, it navigates a complex path through dense foliage and human dwellings, adapting to these contrasting environments.

Brazilian Wandering Spider Behaviour and Adaptations

Brazilian Wandering Spiders are known for their nomadic behavior. Instead of building webs to catch prey, they actively hunt at night, using their highly developed senses, particularly vision, to locate and stalk their prey.

These arachnids have adapted to a wide range of habitats, from forests to urban areas. Their potent neurotoxic venom, one of the most powerful among spiders, allows them to incapacitate and consume a variety of prey.

Brazilian Wandering Spider Interaction with the Ecosystem

Now, let's look at how they help maintain the balance in the ecosystem:

  • Brazilian Wandering Spiders play a crucial role in controlling the population of their prey, which includes insects and small mammals.
  • They serve as a food source for larger animals, contributing to the food chain in their ecosystem.
  • Their venom, although dangerous to humans, is studied for medicinal purposes including treatments for erectile dysfunction and pain relief.

Threats to Brazilian Wandering Spider

Despite their popularity and predator status, Brazilian Wandering Spider encounter several threats as well:

  • Destruction of natural habitat due to deforestation
  • Increased usage of pesticides affecting their food chain
  • Climate change potentially disrupting their breeding patterns

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Brazilian Wandering Spider: Care, Food, Habitat & Preventions

Mike Wallace

Have you ever heard of or do you know what a  Brazilian wandering spider is ? It is a big venomous spider from places like Central and South America, and people sometimes call it the  banana spider . Why? Well, we are about to find out!

Table of Contents

These wandering spiders are aggressive hunters who go out on the hunt at night. Their meals include both invertebrates (like insects) and vertebrates (creatures with a backbone, like small animals).

These spiders are super dangerous because their venom is like a powerful potion that can make people really sick or even worse. They usually hang out in tropical rainforests and even in cities, hiding in banana plants. 

So, let’s get more information about the world of this sneaky spider to learn the details about its looks, eating habits, where it lives, the venom it carries, and find out if it is genuinely risky. Ready to explore? Keep reading!

Brazilian Wandering Spider Description:

Scientific name and family:.

In Brazil, they are sometimes known as “ armed spiders ” (armadeiras), and they share the name “ banana spiders ” with a few other spiders. They have different names, but they are all talking about the same interesting spider!

Brazilian Wandering-Spider sitting on hand Spiders-Planet

The Brazilian wandering spider, scientifically known as  Phoneutria , Maximilian Perty kickstarted the Phoneutria genus in 1833. The name comes from the Greek word φονεύτρια , which means “murderess” and falls under the Animalia kingdom, Arthropoda phylum, and Arachnida class.

Within Arachnida, it is classified in the order Araneae, infraorder Araneomorphae, and Ctenidae family. The genus Phoneutria, described by Perty in 1833, includes the type species  Phoneutria fera .

This classification helps us understand where these spiders fit into the larger picture of living organisms.

The following 9 species are accepted by The  World Spider Catalog :

  • Phoneutria bahiensis
  • Phoneutria boliviensis
  • Phoneutria eickstedtae
  • Phoneutria fera
  • Phoneutria keyserlingi
  • Phoneutria nigriventer
  • Phoneutria pertyi
  • Phoneutria reidyi
  • Phoneutria depilata

What do Brazilian Wandering Spider look like?

Size range:.

The spiders in the Phoneutria group can get pretty big in size. Their legs can stretch out to be 13 to 18 centimeters (5 to 7 inches) wide, and their bodies can have a range between 17 to 48 millimeters (a little more than half an inch to almost 2 inches) long.

The female Brazilian spiders can get pretty big, reaching up to 15 centimeters (5.9 inches) in length. On the other hand, the males are smaller, usually measuring around 7 centimeters (2.8 inches). They usually weigh up to 0.21 ounces.

They have long, slender legs, and even though some other spiders with different names might have longer legs, the Phoneutria spiders are champions when it comes to having the longest bodies and being the heaviest in their spider gang.

The spider’s body has two main parts. The first is the prosoma, kind of like its “head,” where you will find all eight legs, eyes, fangs (chelicera), and little multitasking arms (pedipalps).

The second part is the opisthosoma, holding the spinnerets for making silk, the back end opening (anal opening), “the lungs,” the heart, and the important bits for making baby spiders (reproductive organs).

So, the prosoma is like the front control center, and the opisthosoma is like the back office, handling things like silk-making and baby-making.

Brazilian spiders come in different colors, with most being hairy and shades of brown and gray. Some species may have lightly colored spots on their abdomen.

A distinctive feature of many species is the presence of bands of black and yellow or white on the underside of their two front legs.

Identification:

To identify a spider from the Phoneutria group, look for a dense brush of fine hairs on their leg parts. They might seem like other spiders, especially  Cupiennius , but here is how you can differentiate: 

  • Phoneutria often have a dark line on the front of their palps and a thin black line on top of their head. 
  • Check underneath, too; their legs usually have dark parts and light joints. Sometimes, the belly has black dots or is reddish. 
  • Usually it has been observed that when they are upset, they do a cool defensive move like lifting their front legs high with a distinctive pattern. So, if you see a spider doing that dance, it is probably a Phoneutria!

Brazilian Wandering Spiders live all over the Americas, from Costa Rica to northern Argentina. They are like the residents of the jungle, chilling in forests east of the Andes in countries like Colombia, Venezuela, Ecuador, Peru, Bolivia, Brazil, Paraguay, and the Guianas.

Some, like P. reidyi, P. boliviensis, and P. fera, love the Amazon rainforest, while others prefer the Atlantic Forest in Argentina, Paraguay, and Brazil.

They have also made themselves at home in the Cerrado savanna. But if you head to northeastern Brazil, they are not around. These spiders have even taken trips to Chile and Uruguay.

Why are they called Banana Spiders?

These spiders are linked with bananas. Richard S. Vetter, a researcher at the University of California, found that these powerful spiders sometimes end up in North America and Europe by accident, hitching a ride in banana shipments.

Banana Spider sitting on banana leaf - Spiders Planet

But it is often a case of mistaken identity. Only a few Phoneutria species have been found in banana shipments, and sometimes, other spiders get the blame due to misidentification. 

What They Like to Eat or Hunt?

Their food includes flies, beetles, butterflies, moths, grasshoppers, locusts, and crickets. Occasionally, they might even feast on small creatures like amphibians, reptiles, or mice. All these diet or food findings tell us about how diversified eating habits these fascinating spiders have.

Mating and Lifecycle:

Like most spiders, the female spiders are bigger than the males. When the male spider wants to be friends, they do a little dance (vibrating his pedipalps and specialized sensory appendages) to signal his intentions to impress the female, but it is a cautious approach.

The behavior of the female can be choosy, and she might say no to a few before picking the right one. 

After the dance, sometimes, the females decide to attack them, or if she is interested, she can store the male’s baby-making material in a special place until she is ready to use it.

Then, she lays a bunch of eggs, up to 1,000 at a time, and keeps them safe in a silk egg sac. Sadly, after laying her eggs, the mom spider says goodbye. It is her way of making sure the new spiders are ready to explore the world on their own.

The lifespan of the banana spider (Phoneutria nigriventer) differs for males and females. Females usually live for 6 to 8 weeks after reaching maturity, while males have a shorter lifespan of 2 to 3 weeks after their last molt. 

Certain mammals, like coatis (Procyonidae, which includes raccoons) and other small insectivores, birds are potential predators of large wandering spiders.

These spiders got their name as wandering spiders because of the fact that they are not into web building. Instead, they stroll around the forest floor at night(nocturnal), searching for dinner.

Brazilian Wandering Spiders are active hunters and use both ambush tactics and direct attacks to catch their prey. During the day, they prefer cozy spots like under logs or in crevices, only emerging at night for their hunting adventures. These spiders do not build nests like other spider species.

While wandering spiders are not naturally aggressive towards humans, they won’t hesitate to bite if they feel cornered or threatened. Most bites happen when a spider accidentally gets trapped in clothing or bedding. 

Bite and Venom:

The bite of the armed spider is the most dangerous in the world as the venom it carries can be harmful to humans.

The danger is not just about how strong the venom is; it is also about factors like the spider’s likelihood to bite and how close it is to where people live.

These spiders often hide in houses, clothes, and other dark places during the day, making accidental bites more likely. 

While their fangs are adapted for small prey, some experts think they might give a “dry” bite in defense to save venom. Studies suggest that not all bites inject venom, and serious cases requiring antivenom are rare.

However, there have been confirmed cases of death, with symptoms appearing quickly, including:

  • Severe pain
  • Breathing difficulties
  • Increased heart rate and blood pressure
  • In severe cases, paralysis and death

The severity can depend on the spider’s sex, with females generally more dangerous. The spiders produce less venom in colder months, and a small amount can be potent enough to harm.

Fortunately, bites from Brazilian spiders are rare, and when they do occur, the exposure to the toxins is generally mild, as explained by Vetter.

Also Read: What is a Huntsman Spider? (Heteropodidae) – The Ultimate Guide

Banana Spider’s Facts:

Below are essential details about Brazilian wandering spiders:

  • They hold the title for the world’s largest spiders , boasting leg spans reaching up to 15 centimeters (6 inches).
  • Their venom packs a powerful punch, capable of inducing severe pain, paralysis, and, in extreme cases, fatal outcomes for humans.
  • Despite their intimidating reputation, they are generally non-aggressive and resort to biting only when provoked.
  • These spiders inhabit tropical rainforests and urban areas across Central and South America.
  • In case someone has been bitten by this spider, he/she needs quick medical treatment to control the effects timely.

Brazilian Wandering Spider sitting on wood -Spiders Planet

Treatment and Preventive Measures:

If bitten by a wandering spider or armed spiders, prompt medical attention is crucial. There is an antivenom for the spider’s venom, but its effectiveness is highest when administered within a few hours of the bite.

To prevent a bite:

  • Wear protective clothing, use shoes and long pants when in areas where these spiders are found.
  • Before wearing your clothes and shoes, make sure to check them to ensure no spiders are hiding.
  • Maintain cleanliness and avoid leaving food or garbage exposed, as this can attract spiders.

These preventive measures are essential for minimizing the risk of encountering and getting bitten by Banana spiders.

Can Brazilian spiders kill humans?

Brazilian wandering spiders (Phoneutria nigriventer) are venomous and can potentially kill a human with a single bite. Their venom contains a potent neurotoxin that can cause severe pain, paralysis, and even death. 

Are Brazilian spiders poisonous?

Yes the venom of this spider is poisonous, that can cause death. While Brazilian wandering spiders are potentially dangerous, actual bites are relatively rare.

By adopting preventive measures and promptly seeking medical attention if bitten, the risk of serious complications can be significantly reduced.

Can you keep Brazilian spiders as pets?

It is strongly advised against keeping wandering spiders as pets due to their venomous nature and the potential risk to human safety.

Managing these spiders in captivity demands specialized knowledge and handling procedures to minimize the risk of bites.

Final Thoughts:

The Brazilian wandering spider, banana spider, or armed spider is a large and venomous arachnid found in Central and South America. While their potent venom can be harmful to humans, encounters are rare.

These nocturnal hunters have adopted various habitats, from rainforests to urban areas, and are associated with banana shipments. Understanding their appearance, behavior, and habitat is crucial for minimizing risks.

Seeking immediate medical attention after a bite is essential, as antivenom is available but most effective when administered promptly. Despite their fearsome reputation, the Brazilian spider remains a captivating and potentially dangerous species.

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Although nearly all spiders are venomous, a few stand out from the crowd for their potent toxins. So, which spider is the deadliest in the world?

We see a black funnel web spider with a red mark on its underside. It's on the brown dirt and its four front legs are raised, showing its fangs.

Spiders are common critters. And, as almost all of Earth's 43,000 known spider species are venomous , it is likely that most people have encountered a venomous spider at one point or another. 

So that's the bad news. The good news, however, is that of these, only 25 species are known to have killed or caused serious harm to humans. But which spider is the deadliest?

The deadliest spiders — or at least those most frequently cited as having caused death or serious injury to humans — are funnel-web spiders ( Atrax ), redback and black widow spiders ( Latrodectus ), banana and wandering spiders ( Phoneutria ) and recluse spiders ( Loxosceles ). 

But even these deadly spiders, with potent venom and fangs primed for piercing skin, are not particularly dangerous to humans. The American Association of Poison Control Centers (AAPCC) tracked only one death caused by a spider bite in the U.S. in 2021. Australia, home to some of the most venomous spiders in the world, hasn't reported a single spider bite death since the 1980s . 

"It is incredibly rare to have a deadly spider encounter," said Rick Vetter , a retired research associate with the Department of Entomology at University of California, Riverside, whose research focused on medically important spiders. "Considering all the bad things that could happen to you, if spiders are your biggest concern, then you are living the good life."

Related: Are daddy longlegs really the most venomous spiders in the world?

Funnel-web spiders top the list of deadliest spiders, if only for their storied venom. Native to Australia, these spiders boast venom that's so potent their bite can kill within minutes. "The deadliest is probably the funnel-web spider and its relatives. The Sydney funnel web spider ( Atrax robustus ) can kill a toddler in about 5 minutes and a 5-year-old in about 2 hours," Vetter told Live Science. Although no one has died from these spiders since the advent of antivenom in the 1980s, it is difficult to imagine a toddler receiving treatment soon enough to recover from a funnel-web bite.

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We see a close up of a brown spider with four forward-facing eyes (two on top, two on bottom).

Phoneutria spiders, the most common of which are often referred to as banana spiders or wandering spiders , are native to Brazil and have the most neurologically active venom of any spider. But they rank a bit lower on the list of the world's deadliest spiders because their venom works relatively slowly, leaving ample time for treatment. And Loxosceles spiders, the most familiar of which is the brown recluse ( L. reclusa ) found in the U.S., may be one the most common causes of spider-related injuries, with painful bites that can cause body aches and fever and take months to fully resolve. But they are very rarely deadly. 

The only arachnid genus that gives the funnel-web a real run for its money as the deadliest spider is Latrodectus , which includes the Australian redback ( Latrodectus hasselti ) and the more familiar black widow spider in the U.S. These spiders have a slight edge because they bite humans more frequently than funnel-web spiders, with comparably potent venom. "The most venomous species (Sydney funnel-web spiders, Brazilian wandering spiders) don't kill or impact that many people," Linda Rayor , a behavioral ecologist at Cornell University who focuses on spiders, told Live Science in an email. "It is the more widely-distributed black widows that are going to be the stars of your story."

It's important to note that, while AAPCC's annual reports carve out a section for spider bite statistics, it isn't easy to get a real handle on spider bite mortality or morbidity. 

"A number of human deaths each year are attributed to spiders," Rod Crawford , curator of arachnids at the Burke Museum at the University of Washington in Seattle, told Live Science in an email. "However, from a scientific viewpoint, almost none of these attributions are evidence-based." 

Related: 11 deadliest spiders

It is exceedingly rare, Crawford explained, for a victim to see a spider on their skin, feel a bite, capture that same spider, and then bring the offending spider to a physician (let alone a spider specialist) for analysis. "Practically all of the 'spider bites' you hear about, including those reported to poison centers originate from the belief that if you didn't see what bit you, it was a spider," Crawford said. 

Rayor echoed this sentiment. "I have spent a surprising amount of time trying to track down the human mortality rate from spiders and it is miniscule," she said. "This isn't reliably reported, but it is clear that not that many people get killed by spiders."

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Keeping in mind the flawed nature of spider bite statistics, The Australian Museum claims that about 2,000 people are bitten by redback spiders each year, and that the antivenom to treat funnel-web spider bites has been given to about 100 patients since 1980. AAPCC's annual report tracked about 3,500 spider bites in the U.S. in 2021, with about 40 "major" clinical outcomes. Nine of those serious outcomes were attributed to black widows; 29 major outcomes and the only death that year were attributed to brown recluses. There were no spider bite deaths in AAPCC's 2020 report , which tracked seven "major" black widow bites and 23 "major" brown recluse bites.

This means that the deadliest spiders are, in fact, not very deadly. "True human spider bites of any kind — dangerous or harmless — are vanishingly rare," Crawford said. "Take me as an example: Over a long career I have handled tens of thousands of live spiders with my bare hands. Only 3 actual bites resulted; none of the 3 had any significant effect. So when people tell me spiders crawl into their beds at night and bite them while they are asleep, I just roll my eyes."

Vetter agreed. "In reality, spiders are way down the list of things to be concerned about."

Joshua A. Krisch is a freelance science writer. He is particularly interested in biology and biomedical sciences, but he has covered technology, environmental issues, space, mathematics, and health policy, and he is interested in anything that could plausibly be defined as science. Joshua studied biology at Yeshiva University, and later completed graduate work in health sciences at Cornell University and science journalism at New York University.

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wandering spider poisonous

Animals Around The Globe

The World’s Most Venomous Spider: The Brazilian Wandering Spider

Published: August 10, 2023

wandering spider poisonous

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Few things fear people’s hearts, like the mention of venomous spiders. According to the Guinness World Records , venomous spiders are some of the most dangerous creatures on Earth, and the Brazilian Wandering Spider is the world’s most venomous spider. This elusive arachnid is found in the rainforests of South America, more specifically in Brazil, Argentina, and French Guiana. ‘

It is considered one of Brazil’s most significant public health threats, with a potent venom capable of causing extreme pain, paralysis, and even death. Despite its fearsome reputation, however, the Brazilian Wandering Spider is a fascinating and unique creature with many incredible features that make it stand out from other spiders.

Brazilian wandering spider

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Brazilian Wandering Spider’s Habitat And Range

Brazilian wandering spider

The Brazilian Wandering Spider is found in the rainforests of South America. These rainforests are the world’s largest and most biodiverse terrestrial ecosystems, covering an area of approximately 6.7 million square kilometers. This equates to roughly 40% of the total area of South America and spans nine countries, including Brazil, Peru, and Colombia.

The Amazon rainforest, the most extensive rainforest on Earth, plays an essential role in the Brazilian Wandering Spider’s habitat and range. The spider relies heavily on the dense canopy of trees in these rainforests for shelter and protection. The Amazon rainforest also provides the spider with an abundant prey source, including insects, small mammals, and other spiders.

The South American rainforests are characterized by their warm and humid climate, which creates the ideal conditions for the Brazilian Wandering Spider to thrive. These ecosystems also have a high rainfall throughout the year, which sustains the dense vegetation and creates an ideal environment for spiders to hunt and reproduce.

Check out: Uncovering The Enigma Of The Greenland Shark .

Specific Locations The Brazilian Wandering Spider Is found

The Brazilian Wandering Spider is most commonly found in Brazil. It can also be found in other parts of South America, such as Argentina and French Guiana. In Brazil, the spider can be found in various regions. This includes the Amazon rainforest, the Atlantic forest, and the Caatinga ecosystem.

The Atlantic forest, a tropical forest that spans the Brazilian coast, is also an important habitat for the Brazilian Wandering Spider. This ecosystem is under threat due to deforestation and urbanization. This has resulted in the loss of the spider’s natural habitat.

In French Guiana, the spider is present in the Guiana Amazonian Park, a protected area of the Amazon rainforest managed by the French government. The Guiana Amazonian Park is home to an array of biodiversity, including monkeys, jaguars, and over 400 species of birds. This makes it an important region for the Brazilian Wandering Spider’s survival.

Brazilian Wandering Spider’s Characteristics

Brazilian wandering spider

It is a remarkable arachnid species found in the rainforests of South America. It has numerous unique characteristics from other spiders. The Spider is large and intimidating, measuring up to 10 inches (25 cm) in leg span. Its body size ranges from 0.98 to 1.77 inches (2.5 to 4.5 cm) in length. This makes it one of the biggest spider species in the world. It has eight long and hairy legs, which help it move quickly and climb trees effortlessly.

The spider is striking, with a shiny brown or black body covered in short fine hairs. Its legs are also covered in fine hairs with dark stripes or spots. These markings have a unique pattern that helps to identify the spider from other species. Unlike most spiders, the Brazilian Wandering Spider doesn’t have a distinct web-spinning organ. But instead moves around the forest floor and trees in search of its prey.

Behavioral Patterns

They are aptly named because they are known to wander about and can cover a great distance while searching for food and mates. It’s primarily active at night and is a solitary hunter that preys on insects, spiders, rodents, and even small snakes. It has a unique hunting technique where it grabs its prey with its front legs and sinks fangs into it, injecting a potent venom that can quickly immobilize and kill its victim. Interestingly, this spider can adjust the amount of venom it injects to fit the size and the species of its prey, a skill unique to this spider species.

During the mating season, the Brazilian Wandering Spider’s behavior changes drastically. The males will approach females cautiously, tapping on the female’s web to signal their interest. They then perform a complex courtship display that involves waving their front legs, drumming their pedipalps, and vibrating on webs. The more intricate the display, the higher the chances of mating with the female.

Brazilian Wandering Spider’s Venom

Brazilian wandering spider

The venom of the Brazilian Wandering Spider is considered one of the deadliest in the world. The potency of the venom is due to the presence of a potent neurotoxin called PhTx3. This toxin is responsible for the spider’s ability to paralyze its prey and defend itself from predators.

In scientific studies, the venom of the Brazilian Wandering Spider has proven to be significantly more toxic than other venomous spiders, such as the Black Widow and the Brown Recluse. The effectiveness of this venom is a result of its unique chemical structure, which allows it to attack the nervous system of its victim and cause significant damage.

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Effects Of Venom On Humans And Animals

The effects of the venom of the Brazilian Wandering Spider can be devastating. When bitten, victims may experience severe pain, muscle spasms, and even paralysis. In extreme cases, the venom can cause respiratory failure, resulting in death.

While the venom initially causes pain and discomfort, it can lead to severe, long-lasting symptoms. In addition to causing physical harm, the venom can also have psychological effects, leading to anxiety, panic attacks, and even PTSD.

Animals are also susceptible to the venom of the Brazilian Wandering Spider . Small animals, such as mice and birds, are often preyed upon by the spider, while larger animals, such as dogs and cats, can be bitten accidentally.

Public Health Threat And Prevention

Brazilian wandering spider

The Brazilian Wandering Spider is a significant public health threat in Brazil, with hundreds of bites reported yearly. The spider has a wide distribution throughout the country, and its venom is particularly toxic, making it a serious risk to human health.

Also, the spider is especially dangerous because it is highly aggressive and can be found in homes, gardens, and public spaces. This means that anyone can encounter the spider, regardless of location or occupation, making it difficult to prevent bites.

Measures Taken To Prevent Bites And Treat Victims

To prevent bites from the Brazilian Wandering Spider, it is essential to take steps to reduce the risk of encountering the spider. This may include keeping homes and gardens free of clutter and debris, sealing windows and doors, and avoiding areas where the spider is known to live.

In the case of a bite, it is important to seek medical attention immediately. While no anti-venom is available, medical professionals can offer supportive care to alleviate symptoms and prevent complications.

Frequently Asked Questions

The Brazilian Wandering Spider’s venom contains a potent neurotoxin called PhTx3, which can cause extreme pain, muscle spasms, and paralysis in humans. This venom is 20 times more deadly than a rattlesnake’s and can cause respiratory failure in victims.

It is primarily found in South and Central America, especially in the Amazon rainforest. They hide in dark, moist environments such as piles of leaves, tree trunks, and burrows.

To avoid contact with the Brazilian Wandering Spider, it is important to inspect your surroundings, especially before putting on shoes or reaching into piles of debris. It is advisable to wear gloves and long sleeves when working outdoors or in areas where these spiders may be present. If you suspect a Brazilian Wandering Spider has bitten you, seek medical attention immediately.

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Overall, the Brazilian Wandering Spider is a fascinating and deadly spider that deserves respect and caution. Though its venom is incredibly potent, the spider itself is a remarkable creature. Its ability to move quickly and seamlessly across the ground makes it a formidable predator in its native habitats. 

Despite its fearsome reputation, we must learn to coexist with this remarkable arachnid, preserving its unique place in the natural world. Given the immense diversity and beauty of our planet’s biodiversity, the Brazilian Wandering Spider reminds us that we still have much to learn about the remarkable creatures that share our planet.

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wandering spider poisonous

Can a Bite From a Brazilian Wandering Spider Cause a Four-Hour Erection?

In many cases, the erection is merely an early warning before the complete shutdown of multiple organ systems., alex kasprak, published aug. 16, 2023.

True

About this rating

On Aug. 14, 2023, the account First Doctor  posted what it asserted to be an "exclusive" finding on the social media platform X, formerly known as Twitter:

wandering spider poisonous

While far from an exclusive — or even a remotely new — finding, the two claims in the tweet were factual. A bite from Phoneutria nigriventer , commonly known as the Brazilian wandering spider, can indeed result in a long-lasting and painful erection, a condition known as priapism when it lasts more than four hours . 

While the toxicity and high risk of death posed by the chemical thought to be responsible for the erections makes its use as a potential erectile dysfunction (ED) therapy challenging, if not literally impossible , it has been used to develop similar chemicals that may have therapeutic potential. 

Phoneutria nigriventer 's erection-causing effects have been known to science since the 1970s. The 1971 book "Venemous Animals and Their Venom" described priapistic effects of this spider's bite on mice and dogs. The authors also included anecdotal reports from humans who had been bitten:

A pattern which resembles that of dog envenomation is also noticed in humans bitten by Phoneutria nigriventer: local unbearable pain, salivation, visual disturbances, sweating, prostration, priapism, and death. 

Research published in 2008 identified the chemical within the venom likely responsible for the erections — a peptide now named PnTx2-6. "[Pn]Tx2-6 enhanced erectile function in [...] rats, via the [Nitrous Oxide] NO pathway," the study reported. "Our studies suggest that [Pn]Tx2-6 could be important for development of new pharmacological agents for treatment of erectile dysfunction."

The interest in this toxin as a treatment for ED stems, in part, because it operates in a completely different way than common ED treatments like Viagra, as reported in 2011 by NBC News:

Viagra, Levitra and other ED drugs on the market work by inhibiting an enzyme called PDE5. To get an erection, a man's body must release nitric oxide, which relaxes the smooth muscle around the arteries of the penis, allowing for his blood vessels to dilate. The nitric oxide is a first step in a series of chemical reactions that allow this muscle relaxation to take place.  One step in the series is cGMP, a signaling molecule that acts to keep the muscles relaxed. PDE5 degrades cGMP. That's a good thing for ensuring that erections don't last forever, but too much PDE5 can mean an erection doesn't happen at all. By blocking the enzyme, PDE5 inhibitors solve the problem. The spider toxin works differently. Instead of affecting PDE5, the compound seems to trigger nitric oxide release, acting directly to relax the smooth muscles. Because about 30 percent of patients don't respond to PDE5 inhibitors, the toxin could provide an alternative to ED treatments currently on the market, [Study author Kenia] Nunes said." 

In 2022, the same research group responsible for identifying PnTx2-6 published a paper arguing, in part, that due to the extreme pain and high toxicity of the chemical, its "therapeutic use is impossible," but that it is "an excellent pharmacological tool for studying erectile function." That study synthesized a new peptide, PnPP-19, based on the toxic original.

Based on studies performed on laboratory mice, PnPP-19 appears to have the potential to cause erections without the pain or toxicity of the spider venom:

This synthetic peptide also potentiates erectile function via NO/cGMP, but it [...] displays nontoxic properties in animals even at high doses. PnPP-19 effectively potentiates erectile function not only after subcutaneous or intravenous administration but also following topical application.

The assertions in First Doctor's post were factual because the priapism caused by Phoneutria nigriventer's bites have been well-documented and well-studied for decades and because the active ingredients in that venom have been used to investigate new ED therapies. As such, we rate the claim as "True."

Bücherl, Wolfgang, and Eleanor E. Buckley. Venomous Animals and Their Venoms: Venomous Invertebrates. Elsevier, 2013.

Nunes, K. P., et al. "Tx2-6 Toxin of the Phoneutria Nigriventer Spider Potentiates Rat Erectile Function." Toxicon : Official Journal of the International Society on Toxinology, vol. 51, no. 7, June 2008, pp. 1197–206. PubMed Central, https://doi.org/10.1016/j.toxicon.2008.02.010.

Silberman, Michael, et al. "Priapism." StatPearls, StatPearls Publishing, 2023. PubMed, http://www.ncbi.nlm.nih.gov/books/NBK459178/.

Silva, Carolina Nunes da, et al. "From the PnTx2-6 Toxin to the PnPP-19 Engineered Peptide: Therapeutic Potential in Erectile Dysfunction, Nociception, and Glaucoma." Frontiers in Molecular Biosciences, vol. 9, 2022. Frontiers, https://www.frontiersin.org/articles/10.3389/fmolb.2022.831823.

"Spider Venom Shows Promise for Treating Erectile Dysfunction." NBC News, 7 Sept. 2012, http://www.nbcnews.com/health/health-news/spider-venom-shows-promise-treating-erectile-dysfunction-flna1B5794477.  

By Alex Kasprak

Alex Kasprak is an investigative journalist and science writer reporting on scientific misinformation, online fraud, and financial crime.

Article Tags

Venomous wandering spider (Phoneutria fera) in Ecuador.

Top 11 Largest Spiders in the World

Spiders are a type of arachnid , as are mites, ticks , and scorpions . The creatures vary in size , from as small as a couple of millimeters to as large as 11 inches in leg span. Despite there being a plethora of different spiders, they have a similar appearance: an unsegmented body, and four pairs of legs , and they typically have eight eyes, though some may have six or fewer.

Spiders also have organs for producing silk—in other words, the material from which they make nests, webs, or cocoons. Spiders trap and immobilize prey (often smaller insects) with the silk, inject them with paralyzing venom, and then with a predigestive liquid. Finally, spiders suck the nutrients out of and consume their prey.

There are over 50,000 different spiders in the world, scattered all over different ecosystems and environments. Some live on the water, while others live in forests or the desert. The world's largest spiders vary in leg span and body mass. No matter whether one is an arachnophobe or arachnophile, the creatures are sure to inspire a little awe.

Goliath Bird-eating Tarantula ( Theraphosa blondi )

Close-up of a Goliath bird-eating tarantula, the largest tarantula species.

Close-up of a Goliath bird-eating tarantula, the largest tarantula species.

Goliath Bird-eating Tarantula ( Theraphosa blondi ), the biggest tarantulas in the world , live deep in the rainforests of South America , namely Venezuela , northern Brazil , Guyana , French Guiana , and Suriname . They have a deep brown or black coloring, two fangs, and chelicerae and pedipalps (additional appendages) near the mouth that act as fangs and claws and expel venom. The body of a Goliath Bird-eating Tarantula measures up to 4.75 inches, while the leg span reaches 11 inches. The tarantula weighs up to 6 ounces.

The male spiders typically live for three to six years, while females may survive up to 20 years. The creatures protect themselves by making a loud hissing noise or releasing sharp hairs into attackers, and make a meal out of smaller insects and animals, such as birds, mice, frogs, and lizards.

Giant Huntsman Spider ( Heteropoda maxima )

Close-up of Huntsman spiders on wood, Indonesian spiders.

Close-up of Huntsman spiders on wood, Indonesian spiders.

The Giant Huntsman Spider ( Heteropoda maxima ) is only currently known to reside in certain limestone caves within Laos in Asia . The spiders are typically yellow-brown in color, with large black spots scattered irregularly on the back half of the body and dark bands on the legs.

The size of the Giant Huntsman Spider mirrors the leg span of the Goliath Birdeater Tarantula, reaching 12 inches. They typically have a 1.8-inch long body, weighing about 2.6 ounces because of the smaller body when compared to the Goliath Birdeater. However, females typically have larger bodies, while males have longer legs. Birds and small rodents or reptiles sustain the spiders for up to two years.

Brazilian Salmon Pink Birdeater ( Lasiodora parahybana )

Brazilian salmon pink bird-eating tarantula (Lasiodora parahybana).

Brazilian salmon pink bird-eating tarantula (Lasiodora parahybana).

The Brazilian Salmon Pink Birdeater ( Lasiodora parahybana ) is the world's third largest spider, reaching a maximum size of 11 inches, though they typically grow to be 7 to 10 inches and weigh 3.5 ounces. They live in the tropical forests of eastern Brazil , with a velvety black abdomen and salmon-colored hairs from which they get their name.

The Brazilian Salmon Pink Birdeater reaches adult size in just two years. Male spiders live up to five years, while females have a lifespan of 15 years. They have self-protective urticating (prickly or stinging) hairs that cause itching or swelling. Brazilian Salmon Pink Birdeater spiders typically eat large insects or small amphibians or reptiles .

Chaco Golden-knee Tarantula ( Grammostola pulchripes )

Chaco Golden Knee Tarantula (Grammostola pulchripes).

Chaco Golden Knee Tarantula (Grammostola pulchripes).

The Chaco Golden-knee Tarantula ( Grammostola pulchripes ) finds its home in Paraguay or Argentina, enjoying the more subtropical regions . The tarantula is known to reach between 7 to 8.5 inches in leg span. The spiders have mainly black bodies with golden stripes around the legs and pink hairs on the body. Like the Giant Huntsman Spider, males have smaller bodies and longer legs, while females have larger bodies. Also, males often live between five and seven years, while females live around 20 years. To defend itself, the spider may use its urticating hairs or burrow underground.

Face-Sized Tarantula ( Poecilotheria rajaei )

Tarantula: Poecilotheria rajaei.

Tarantula: Poecilotheria rajaei. By Ranil Nanayakkara, CC BY 3.0, Wikimedia Commons

The Face-Sized Tarantula ( Poecilotheria rajaei ) is native to Sri Lanka and India, where it resides in the trees. It is a more recent discovery, as a dead specimen was found in 2009. The spiders are yellow, pink, and gray in color, with unique striping and piping that helps them camouflage in the wilderness. As they are quite rare and live in an area that suffers from deforestation , there is still much to discover about the tarantulas, but they boast a leg span of 8 inches—in other words, they are the size of a human face—and they eat small rodents, birds, lizards, and snakes.

King Baboon Spider ( Pelinobius muticus )

King baboon spider (Pelinobius muticus)

The King Baboon Spider ( Pelinobius muticus ) is an East African spider that lives in the shrublands and grasslands and is a dark reddish brown color. The spiders have urticating hairs, as well as stridulatory hairs, which rub together to create a whistling sound, acting as a defense mechanism. They are similar in size to the Face-Size Tarantula, reaching about 8 inches in leg span. The spiders typically burrow rather than create webs, using their silk near the entrance of their burrow to detect prey, such as beetles and cockroaches, through vibrations from motion. King Baboon Spiders live to be about 20 years.

Colombian Giant Tarantula ( Megaphobema robustum )

Colombian giant tarantula (Megaphobema robustum), also known as Colombian giant redleg. Span of 6 to 8 inches. Found in the tropical rainforests of Colombia.

Colombian giant tarantula (Megaphobema robustum).

The Colombian Giant Tarantula ( Megaphobema robustum ) is another spider typically found in the tropical rainforests of Brazil and Colombia with a leg span of 6 to 8 inches. The tarantulas have a deep black coloring on their body and legs with bright orange hairs. They feed on large insects, small lizards, and mice. Like many other spiders, males live to be about four or five years, while female spiders live to be around 20 years. The Colombian Giant Tarantula is a bit more timid than others, typically burrowing or fleeing at a threat.

Brazilian Wandering Spider ( Phoneutria fera )

Venomous wandering spider (Phoneutria fera) resting on a heliconia leaf in the Ecuadorian rainforest.

The Brazilian Wandering Spider ( Phoneutria fera ) or banana spider is one of the most venomous and deadliest spiders in the world—it makes sense that Phoneutria means "murderess" in Greek. The spider lives in Central and South America, from Costa Rica to Argentina. Their bodies reach about 2 inches in length, while the leg span reaches 7 inches. They are covered in small hairs with a gray/brown coloring and lightly colored spots on the abdomen.

Rather than building webs, they crawl on the forest floor and kill prey with a neurotoxic venom. They prey on flies, beetles, butterflies, moths, grasshoppers, locusts, and crickets and typically only bite larger animals in self-defense. Unlike many of the other world's largest spiders which have long lifespans, the Brazilian Wandering Spider only lives for about one year.

Brazilian Giant Tawny Red Tarantula ( Grammostola anthracina )

Grammostola anthracina spider on the ground.

Grammostola anthracina spider on the ground.

Found in Uruguay , Paraguay , Brazil, and Argentina, the Brazilian Giant Tawny Red Tarantula ( Grammostola anthracina ) has an entirely brown body. Like the King Baboon Spider, the Brazilian Giant Tawny Red Tarantula uses stridulatory hairs as a defense mechanism. They grow between 5.5 and 6 inches and weigh about 6 ounces.

The Brazilian Giant Tawny Red Tarantula feeds on insects or small rodents, amphibians, and reptiles. The spiders are also said to have one of the longest lifespans of spiders, with reports of them surviving over 20 years.

Camel Spider ( Solifugae )

Camel spider (Solpugema sp.) from Ndumo Game Reserve, South Africa.

Camel spider (Solpugema) from Ndumo Game Reserve, South Africa.

Camel Spiders ( Solifugae ) are also known as wind scorpions, sun spiders, or solifuges. The creatures live in dry climates such as the southwestern United States , the Middle East , Mexico , and South Africa. They are not true spiders, sitting somewhere between spiders and scorpions. They are tan or dark brown in color and covered in fine hairs, helping them blend in and protecting them from heat. Reaching 5 to 6 inches in size, they generally feed on termites, beetles, rodents, snakes, lizards, and birds. Like the Brazilian Wandering Spider, the Camel Spider has a lifespan of one year.

Sand-dwelling Huntsman Spider ( Cerbalus Aravaensis )

Cerbalus aravaensis: Biggest spider of the Middle East from Arava Valley preying on Stenodactylus doriae geckos.

Cerbalus aravaensis: Biggest spider of the Middle East from Arava Valley preying on Stenodactylus doriae geckos.

Found in the sand dunes of Israel and Jordan , the Sand-dwelling Huntsman Spider ( Cerbalus Aravaensis ) is the smallest of the world's largest spiders, reaching 5.5 inches in leg span. Similar to the Giant Huntsman Spider and the Chaco Golden-knee Tarantula, males tend to have longer legs while females have larger bodies. The creatures are nocturnal and live underground. They have primarily gray to brown, flattened bodies, ideal for blending in with the landscape and slipping between rocks and tight places. The Sand-dwelling Huntsman Spider feeds on a variety of insects, lizards, and frogs and generally lives for two years or more.

Awe-Inspiring Arachnids: The Largest Spiders Revealed

The title of " World's Largest Spider " may belong to two different species: either the Goliath Bird-eating Tarantula or the Giant Huntsman Spider, each boasting their own weight and leg span. Regardless, the eleven largest spiders are some of the world's most interesting creatures. While some of them are venomous, they are not likely to be crawling around your home. Still, with knowledge of where they reside, arachnophobes are best to plan any upcoming vacations accordingly!

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wandering spider poisonous

15 Types Of Spiders, Ranked By Danger Level

I n the intricate web of the natural world, spiders are often painted as creatures of fear and danger. Yet, beneath the surface lies a reality often overlooked: spiders are typically shy and reserved beings, opting to avoid human interaction whenever possible. According to Kids Health , they only resort to biting when provoked or inadvertently trapped, contrary to the common misconception of them as aggressive predators.

When they do bite, spider bites, despite their notorious reputation, are generally harmless. While all spiders carry poison, not all spiders contain the glands necessary to deliver this poison to humans via bite. Technically, their poison would only cause harm to you if you ingested the spider. However, it's a different story when it comes to venomous spiders. These spiders do have the ability to inject humans with their venom via bites, and some venomous spiders possess toxins that can cause serious harm, leading to potentially severe consequences if not treated promptly. 

While we might all freak out if we see bite marks on our bodies after recently encountering a spider, not all bites warrant a trip to the hospital. But some might. In this ranking, we'll explore 15 species of spiders, each with its unique level of danger if a bite were to occur.

Read more: 13 Creatures To Beware Of When Adventuring In California's Deserts

Cellar Spider

Pholcus phalangioides, also known as "daddy longlegs" or cellar spiders, belongs to the Pholcidae family. Recognized by their elongated legs and delicate appearance, they commonly inhabit dark, humid environments like basements, caves, and cellars, where they construct irregular webs to catch prey.

Cellar spiders are generally considered harmless to humans and typically display non-aggressive behavior. Preferring to avoid human contact, they are shy and reclusive creatures. Interestingly, they are beneficial as they contribute to controlling populations of other pests, such as flies and mosquitoes.

Despite their reputation, there are no documented cases of any pholcid spider biting humans and causing harm. However, a prevalent myth erroneously labels them as one of the most lethal spider species. This myth lacks scientific support, as the venom composition and potency of these spiders have never been formally studied. Studies indicate that if a person were to be bitten, the effects are usually mild and inconsequential. For instance, a 2019 study in Frontiers in Ecology and Evolution found minimal adverse reactions to bites from cellar spiders.

Common House Spider

The common house spider, scientifically known as Parasteatoda tepidariorum, is one of the most widespread and well-known spider species found in human habitats worldwide. Like daddy longlegs, these spiders are often encountered indoors, where they build irregular webs in corners, crevices, and other sheltered areas. However, they are distinguished by their darker ring-like pigmentation on their legs.

The threat level posed by common house spiders is minimal. They are not aggressive toward humans and are more likely to flee than bite when encountered. Additionally, their fangs are not well-suited for penetrating human skin, further reducing the likelihood of bites occurring. If one were to aggravate the common house spider so intensely that it does retaliate with a bite, their venom is relatively mild, rendering their bites typically harmless to humans (via Western Exterminator ). There has only been one case of a serious reaction to a bite by a common house spider, but this was because the victim was allergic (via the  University of Florida IFAS ).  

Yellow Sac Spider

The yellow sac spider, scientifically known as Cheiracanthium inclusum, is a globally distributed species found across various regions, including North America. These spiders are easily recognizable by their pale yellow to light green coloration. Despite their relatively lower profile compared to other spiders, yellow sac spiders have garnered interest due to their unique web-spinning behavior. Instead of the intricate webs commonly associated with spiders, they construct sacs using their silk, a behavior noted by Truly Nolen .

Regarding their potential danger to humans, yellow sac spiders are considered medically significant, although the extent of their threat remains a subject of debate. A study published in the American Journal of Tropical Medicine and Hygiene has shed light on this issue. The study discovered that in many cases where people thought yellow sac spiders caused severe reactions, subsequent searches didn't find any of these spiders nearby. The researchers suggested that in these cases, other bugs were probably the real culprits. However, because yellow sac spiders are common, they often get blamed for the bites.

In a comprehensive multi-year study covering the United States and Australia, these researchers confirmed that yellow sac spiders were involved in only about 20 reported spider bite cases. Usually, these bites caused intense pain around the bite spot, but symptoms didn't last long, and most people didn't need medical help, suggesting that yellow sac spiders do not serve the dangerous reputation they have garnered.

Jumping Spider

Jumping spiders, members of the Salticidae family, are renowned for their agility, acute vision, and unique hunting techniques. With a staggering diversity of over 5,000 described species inhabiting various ecosystems worldwide, these spiders stand out as some of the most charismatic and easily identifiable arachnids.

Despite their prevalence, jumping spiders are generally harmless to humans. Research cited in a Toxicon study suggests that although they account for around 5% of spider bites in Australia, their bites are typically mild and pose minimal risk. Affected individuals may experience minor discomfort, redness, and swelling akin to a mosquito bite at the site of the incident (via PestWorld ). Severe reactions or systemic effects are exceptionally rare and usually occur in individuals with heightened sensitivity or allergies to spider venom, according to PestWorld. It's important to note that jumping spiders are more inclined to leap away from humans than to engage in aggressive behavior, further minimizing the likelihood of encounters resulting in bites.

Huntsman Spider

Ah, the huntsman spider -- every Aussie's unofficial roommate, lurking in the corners of homes, sheds, and garages, always ready to surprise you with its impressive size and lightning-fast movements. Belonging to the family Sparassidae, these giants of the spider world are known for their agility and distinctive appearance that can send shivers down your spine faster than a kangaroo hopping by. But fear not! Despite their formidable size and fearsome reputation, huntsman spiders are actually quite beneficial. They happily feast on insects, playing a crucial role in keeping pest populations in check.

While huntsman spiders aren't shy about defending themselves if provoked, their bites are usually more of a nuisance than a cause for alarm. Think of it as similar to the annoyance of a bee or wasp sting: pain, redness, and swelling at the site of the bite (via Miche Pest Control ). Severe reactions or systemic effects are about as rare as finding a drop bear in your backyard. Only those with extreme sensitivity or allergies to spider venom need to worry, and even then, encounters are few and far between. So, rest easy knowing that your eight-legged roommates are more likely to skedaddle than show any aggression toward you.

Wolf Spider

Embodying the true essence of "lone wolves," these spiders have earned their name. Solitary by nature, the wolf spider, belonging to the family Lycosidae, lives and hunts independently, only coming together during mating season in the fall. With over 200 described species scattered across North America alone (via Terminix ), wolf spiders stand as one of the most prevalent and diverse spider families.

In terms of threat to humans, wolf spiders pose minimal danger. Preferring solitude, they typically steer clear of human interaction whenever possible. However, they may venture into human habitats in pursuit of prey or refuge, especially where their natural environments intersect with urban areas.

Despite their imposing size and appearance, wolf spiders are far from aggressive toward humans. When encountered, they're more inclined to flee than to bite. While their bite can be painful if provoked or threatened, their venom is relatively weak and rarely poses any serious risk to humans. Symptoms typically resemble those of a bee or wasp sting, including pain, redness, and swelling at the bite site. Severe reactions or systemic effects are exceedingly uncommon and usually occur in individuals with specific sensitivities or allergies to spider venom.

Hobo Spider

The hobo spider, scientifically known as Tegenaria agrestis, has earned notoriety for its perceived danger to humans, particularly in the Pacific Northwest region of North America. Despite the fact that they are mostly confined to this area, hobo spiders are often erroneously assumed to be present throughout the United States. This misconception has led to misdiagnoses of bites, even in areas where hobo spiders have never been documented, suggesting an overestimation of their danger based on reputation rather than actual evidence (via Catseye Pest ).

The idea that hobo spiders can cause skin damage in North America is based on only a little bit of evidence. Some research says hobo spider venom might cause serious skin wounds in people, but other studies say there isn't enough proof for this. Actually, there's only one confirmed case of a serious skin wound from a hobo spider bite in medical records, according to a study in the Annals of Emergency Medicine.

This lack of clear evidence makes it uncertain how dangerous hobo spiders really are to people. It's important to be careful when considering how much harm they might cause. Despite their reputation, there isn't strong evidence linking hobo spiders to serious skin wounds. So, it's vital to carefully assess claims about their danger and not just rely on stories or what people commonly believe. Overall, hobo spiders are considered to pose a relatively low risk to humans. 

Tarantulas, belonging to the family Theraphosidae, are large and hairy spiders commonly found in various habitats such as burrows, tree hollows, and rock crevices. While they are often encountered outdoors, they may also venture into homes in search of prey or shelter.

Despite their fearsome reputation, tarantulas are typically not aggressive towards humans and are even kept as pets due to their docile nature. While they may exhibit defensive behaviors if threatened, they are more likely to retreat than to bite. In instances where tarantulas do bite, they often deliver dry bites that may cause pain but do not inject venom. In the rare cases where venom is injected, their venom is actually relatively weak and not usually harmful to humans (via Western Exterminator). Thus, the average, healthy adult human does not need to worry about tarantulas. They actually play crucial roles in ecosystems as predators of insects and other small animals and don't necessitate the fear that they usually evoke. 

Brown Recluse Spider

The brown recluse spider, scientifically known as Loxosceles reclusa, is a venomous spider species primarily found in the central and southern United States. Notorious for its venom, which can cause tissue-destroying wounds, brown recluse spiders tend to inhabit dark, secluded areas like basements, attics, closets, and woodpiles.

The threat level posed by brown recluse spiders is higher compared to many other spider species due to the potential severity of their bites. Their venom can induce various symptoms, ranging from mild irritation to severe tissue damage and systemic effects. Nonetheless, it's crucial to highlight that bites from these spiders are relatively uncommon, and not all bites lead to severe symptoms. Most bites result in mild reactions like redness, pain, and swelling at the bite site, akin to a bee or wasp sting.

Individuals bitten by a brown recluse spider may notice redness, pain, and swelling in the affected area.  My Health Alberta recommends seeking medical attention promptly, especially if symptoms progress to blistering, ulceration, or tissue death. In severe cases, systemic symptoms like fever, nausea, vomiting, and muscle pain may also manifest. Timely medical intervention is vital to prevent complications and aid in healing.

Brown Widow Spider

The brown widow spider, closely related to the black widow, is found in warm climates worldwide, including North America, Africa, Asia, and Australia. While brown widow spiders primarily inhabit outdoor areas such as gardens and yards, they may enter homes seeking shelter. 

Despite being less aggressive than black widows, brown widows may bite if threatened. Still, the brown widow's bites are less common due to their more timid behavior and lower abundance.

Although its venom is similar to the black widow's and still considered medically significant, brown widow bites are typically less potent and cause milder reactions. Symptoms of a brown widow bite include pain, redness, swelling, and occasionally muscle cramps. In rare cases, more severe symptoms such as nausea, vomiting, headache, and fever may occur, and there has even been one report of a victim requiring hospitalization. Although brown widow venom is as toxic as other widow species, it's typically viewed as having a weaker effect on humans, likely due to the smaller amount of venom injected during a bite (via UC Riverside ).

Red Widow Spider

The red widow spider, named for its vibrant red coloration, is a native species found exclusively in Florida. Similar to other widow spiders, it possesses potent venom capable of causing various symptoms in humans, similar to those of other spider bites.

One distinctive aspect of the female red widow's bite is the presence of a neurotoxin that induces sustained muscle spasms. This characteristic underscores the importance of seeking medical attention if bitten by a red widow spider. Despite this potential danger, documented cases of injuries or fatalities attributed to red widow spiders are rare. This rarity is likely due to the limited spaces in which humans commonly encounter these spiders, given their range is typically limited to Florida. Still, to prevent any chance of a bite, Imagine Our Florida recommends wearing gloves when picking up wood and other items where red widows may have nested, given that they have been known to make homes in sheds and garages. 

Black Widow Spider

Renowned not only as a popular comic book character, the female black widow spider is oft-labeled as one of the most notorious and venomous spider species in North America. Its habitat extends to parts of Europe, Asia, and Australia. Distinguished by its shiny black appearance and the iconic red hourglass-shaped marking on its abdomen's underside, the black widow spider is instantly recognizable. Known for their defensive behavior when disturbed, black widow spiders may bite humans, albeit infrequently due to their secretive nature. 

Armed with potent neurotoxic venom, the black widow's bite can induce a spectrum of symptoms like severe pain, muscle cramps, nausea, vomiting, or breathing difficulties (via Nature Conservancy Canada ). Although permanent disability or death is uncommon, black widow bites can cause severe pain and painful muscle contractions, emphasizing the importance of seeking medical care promptly, particularly for vulnerable individuals. Compared to other widow spiders, the black widow's venom is particularly potent, which is why its threat level is elevated compared to other widow spiders. 

Australian Redback Spider

The Australian redback spider, Latrodectus hasselti, native to Australia, is akin to the black widow spider in characteristics, including the red marking on its abdomen (via Australian Museum ). Found across Australia, particularly in urban areas, it's a medically significant species due to its potent neurotoxic venom. Though only the female's bite poses a threat, individuals should seek medical attention promptly since it's hard for the average person to be certain of whether they were bitten by a male or female. 

Though less likely to bite unless disturbed, when provoked, redback spiders may bite in defense or when trapped.  Symptoms of a bite include severe pain, sweating, weakness, nausea, and vomiting. Antivenom is available, and deaths post-antivenom introduction are unheard of, though they have occurred in rare cases in the past. 

While fatalities are uncommon, severe reactions are possible, particularly in vulnerable populations. Practicing caution to avoid encounters and seeking immediate medical help if bitten are crucial steps to manage risks associated with Australian redback spiders.

Brazilian Wandering Spider

The Brazilian wandering spider, Phoneutria spp., found in South and Central America, is known for its highly venomous bite and aggressive hunting behavior. Unlike web-building spiders, these arachnids actively roam forest floors at night to hunt prey. Notably, their venom is infamous for causing painful and prolonged erections, as seen in a 2008 study by BJU International.

Symptoms of a bite include burning pain, sweating, and systemic effects such as blood pressure fluctuations, nausea, abdominal cramping, vertigo, and convulsions. Despite their potency, spiders typically do not inject all their venom during a bite, as it's also needed for hunting. Envenomations are generally mild, with only a small percentage requiring antivenom. Roughly 4,000 bites occur annually in Brazil, with few cases being severe and only 15 deaths reported since 1903, according to Live Science . Prompt treatment with antivenom and supportive care can mitigate venom effects and prevent complications.

Sydney Funnel-Web Spider

The Sydney funnel-web spider, Atrax robustus, native to Australia, is infamous for its potent venom and aggressive behavior, especially among males during mating season. Considered one of the world's most dangerous spiders, its bites pose significant risks to humans. Their venom contains a potent neurotoxin, inducing severe symptoms like intense pain, muscle spasms, respiratory distress, and even death in severe cases. Prompt medical attention is crucial to administer antivenom and manage symptoms effectively.

With their aggressive nature and tendency to enter human habitats, encounters with Sydney funnel-web spiders carry an extremely high threat level. Male spiders, more active at night, often enter homes during mating season, increasing human encounters, as reported in a study in the National Library of Medicine . Fatalities are usually associated with male spiders, known for their wandering behavior. The onset of severe symptoms is rapid, with death possible within 15 minutes to three days, especially in children or those with underlying health conditions. Thus, immediate medical attention is imperative for anyone bitten.

Applying a pressure immobilization bandage can help slow venom spread while cleaning the bite site with soap and water and applying a cold compress can reduce pain and swelling. While fatalities are rare due to antivenom availability and prompt treatment, severe reactions can be life-threatening, especially in untreated cases or individuals allergic to spider venom. Encounters with Sydney funnel-web spiders should be treated seriously. 

Read the original article on Outdoor Guide .

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3 reasons venomous ‘flying’ spiders aren’t so scary, from a biologist.

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The Joro spider is a giant among spiders, with females growing to the size of a human palm. People ... [+] are worried about their spread, but here’s why the invasion isn’t as scary as it may seem.

There are over 50,000 species of spiders in the world , but it’s the Joro spider that has large parts of the East Coast on edge.

Originating from East Asia, particularly Japan, China and Korea, Joro spiders ( Trichonephila clavata ) stand out for their striking size, almost villainous appearance and their stowaway-approach to migration —they don’t exactly fly. Experts believe the Joro spiders spread to other regions of the world by “flying” their way on to human transportation systems, most likely cargo ships. That’s why arachnophobes in the United States are worried the spiders could show up in the East Coast cities this summer .

But don’t panic yet. Here are three essential facts to consider before getting caught up in the frenzy about the Joro spiders.

1. Joro Spiders Are Venomous, But Unlikely To Hurt Humans And Pets

Unless you have a tendency to itch yourself to death, a Joro spider’s venom is unlikely to do any serious damage to you. The same goes for any pets in your household. The worst possible outcome is an allergic reaction and the best possible outcome is that you (or your pets) will never have to engage in a face-off, as these arachnids are extremely shy.

Despite the colorful aposematism , Joro venom is not very effective on creatures larger than the typical insect.

While the brilliant color of Joro spiders suggests that they are highly venomous, this is not the ... [+] case.

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Best 5% interest savings accounts of 2024, 2. joro spiders could positively impact local ecology.

Last year, researchers collected 213 female Joro spiders from their webs in Georgia and South Carolina to analyze their diets. Sexual dimorphism (a biological phenomenon in which males and females of the same species exhibit different physical characteristics beyond their sexual organs) is pronounced in these spiders.

Females are not only larger, with leg spans that can extend up to 4 inches, but are also more vividly colored. They typically showcase a brilliant yellow on their bodies with striking blue and red markings, making them easy to tell apart from males, which are significantly smaller and less colorful, predominantly featuring a subdued blue-black hue that makes them less noticeable.

The researchers examined both the spiders’ guts and the remains of prey found in their webs. By identifying what these spiders eat, they were able to infer their role in the local ecosystem. This provides valuable clues as to what could happen if the spiders made their way to the tristate area.

Joro spiders have a varied diet that includes many types of insects, some of which are considered pests, according to the paper published by these researchers. Here’s a quick look:

  • Beetles and flies, which can sometimes be pests
  • True bugs like aphids and stink bugs, known for damaging plants by sucking their sap
  • Wasps, bees and ants, which can be bothersome in large numbers, though they are often beneficial
  • Moths and butterflies, whose larvae can be agricultural pests
  • Mosquitoes, notorious for spreading diseases and being a general nuisance

Based on these findings, Joro spiders could significantly contribute to natural pest control if they establish themselves in the East Coast. Their ability to consume a wide range of insects that are often detrimental to agriculture and human comfort suggests they could help more than harm.

3. Joro Spiders Can ‘Fly,’ But Not Like A Winged Insect Can

Like a few other species of spiders, Joro spiders utilize a fascinating method of movement known as “ballooning” to travel. This doesn’t involve wings; instead, young spiders and sometimes adults release long strands of silk that catch the wind, parachuting them into the air and carrying them over potentially vast distances. This method of dispersal can be quite effective, allowing these spiders to colonize new areas rapidly.

The concept of venomous spiders flying through the air can seem alarming, but it’s important to note that while ballooning enables Joro spiders to move to new regions, it doesn’t mean they will have control on where they’ll land, or that they’ll thrive everywhere they land. Local climate, availability of food and other ecological factors will play crucial roles in determining their success in new environments.

Within the country, Joro spiders are currently found primarily in Georgia. Although ballooning aids their spread, the species is more likely to reach the tristate area by hitchhiking on interstate vehicles. As part of their ongoing U.S. tour, Joro spiders have also been observed in South Carolina, North Carolina and Tennessee, with some reports of their presence in Oklahoma, West Virginia and Maryland.

Despite the recent hoopla about the Joro spider spreading across the U.S., the best thing to do, as fellow residents of the planet, is to let these shy, industrious web-weaving creatures be—especially since they are likely helping us control pest populations.

Scott Travers

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Are Joro Spiders Venomous? What to Know About the Giant Flying Spiders

Experts explain what to know about Joro spiders and if they’re poisonous.

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Are Joro spiders venomous?

Do joro spiders bite, what states are joro spiders in, where are joro spiders coming from, what do joro spiders look like, joro spider size, what to do if you come across a joro spider.

  • Joro spiders are spreading in the U.S.
  • These giant flying spiders have distinct markings.
  • Experts explain if Joro spiders are poisonous.

Few things freak people out like spiders. And when they’re giant venomous flying ones, all bets are off. Joro spiders, which have four-inch legs and balloon through the sky, will potentially invade the New York area sometime this year, according to the New Jersey Pest Control . That’s understandably raising a lot of questions, including “are Joro spiders poisonous?”

Meet the experts : David Coyle, Ph.D., invasive species expert at the University of Clemson; José R. Ramírez-Garofalo, an ecologist at Rutgers University's Lockwood Lab; Andy Davis, Ph.D., a research scientist in the Odum School of Ecology at the University of Georgia; Jim Fredericks, Ph.D., entomologist and senior vice president of public affairs at the National Pest Management Association (NPMA)

The arachnids originally invaded the U.S. from Japan, and they’re expected to stick around. But what is a Joro spider and how concerned about them should you be? Here’s the deal, according to bug experts.

What is a Joro spider?

Joro spiders are large, venomous spiders with four-inch long legs, says David Coyle, Ph.D., invasive species expert at the University of Clemson.

“Joro spiders are a species of orb-weaving spiders—like what you might see in your garden during the summer—that are native to Asia,” says José R. Ramírez-Garofalo, an ecologist at Rutgers University's Lockwood Lab. “Within the last 10 years, they were introduced into the southeastern United States, and have since established themselves.”

These spiders can fly, too. They use a technique called “ballooning,” where they release silk threads into the air that allow them to be carried by the wind. That said, you won’t see large Joro spiders flying around.

“The teeny ones that are young and the size of a poppy seed will let off some strands and get carried by the wind,” Coyle says. “But the big yellow ones we see are not flying. The laws of physics prevent that.”

This is a little complicated. Joro spiders are venomous, meaning they make venom, Ramírez-Garofalo says. But all spiders are venomous, he points out. “Joro spiders are technically venomous, but their venom is not thought to be harmful to humans,” he says.

Andy Davis, Ph.D ., a research scientist in the Odum School of Ecology at the University of Georgia, says he’s asked about this a lot. “The short answer is yes and no,” he says. “All spiders will bite you if you pick them up and handle them harshly. But if you leave them alone, they won’t bother you.”

Joro spiders can bite, but they’re unlikely to. “Joro spiders are really, really shy as far as spiders go,” Davis says, noting that he’s tested this in his lab. “Joro spiders are one of the shiest spiders ever documented,” he says. “Even though they look scary, they’re really docile.”

But bites can still happen, especially if you startle or scare a Joro spider. If you did happen to be bitten by a Joro spider, Davis says it would feel like a bee sting. “Your skin would have the same reaction as a bee sting, too,” he says.

Meaning, you should be just fine if a Joro spider bites you. “Unlike black widow and brown recluse spiders, Joro spiders are not considered a threat to human health,” says Jim Fredericks, Ph.D., entomologist and senior vice president of public affairs at the National Pest Management Association (NPMA) .

Research published in 2023 found that Joro spiders have been detected in these states:

  • North Carolina
  • South Carolina
  • West Virginia

“They are definitely in Georgia, along with the Carolinas and Tennessee,” Doyle says. But the other states where Joro spiders have been spotted may only have a few of these spiders versus having an established population, he says.

Joro spiders are native to Japan, and it’s not entirely known how they got here. “They likely arrived in the U.S. by hitchhiking on vehicles and shipping containers from their native East Asia,” Ramírez-Garofalo says. They’re thought to have originally arrived around 2010 , according to research.

From there, they’ve ballooned or hitchhiked to other parts of the country. “They’re hitchhiking on cars—that’s how they’re getting to these more extensive states,” Davis says.

Joro spiders have established themselves in the U.S. and aren’t expected to leave. “There is no stopping their spread at this point,” Davis says. “There are millions of them. They will be here with us forever. We need to learn to live with them.”

Joro spiders have a distinct look that makes them easy to spot. These spiders have blue-gray and yellow coloring with red markings on the abdomen and black legs with yellow bands for females, Fredericks says. The males are “mostly brown,” he adds.

trichonephila clavata joro spider in the green background

Joro spiders can get pretty big. “The Joro spider is known for its large size compared to other U.S. spider species,” Fredericks says.

Female Joro spiders can be up to 4 inches, including the legs. But male Joro spiders are “much smaller,” with a body size of about 0.25 inches with “drab yellow and brown coloration,” Fredericks says.

Experts say it’s best to just leave Joro spiders alone if you can. “It’s not out to get you,” Coyle says.

A Joro spider is also unlikely to end up inside your home, Davis says. “They do not go into homes,” he says. “They’re fine living in a tree or bush or on your garage. At this point, there hasn’t been any documented evidence that they live in people’s houses.”

Instead, Joro spiders like to set up shop in bushes, porches, carports, and decks, Coyle says. If one is in your way, Coyle suggests removing it with a brush. “They also have very soft bodies—you can squish it,” he says.

Davis says that Joros have a seasonality: They’re tiny in the early summer, about the size of a grain of rice, and then grow to a more noticeable size in September and October. “They die off in the winter,” he says.

Overall, experts stress that there’s no reason to be scared of Joro spiders. “I’ve handled dozens of them already,” Coyle says. “They’re just out there, doing their spider thing.”

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Are 'giant, flying' joro spiders really taking over the U.S.?

The black-and-yellow arachnids are making headlines again, but scientists say not to be alarmed.

A Joro Spider between branches.

Joro spiders are in the news again, and judging by the headlines, everyone is doomed.

“Giant venomous flying spiders… heading to New York area,” says CBS News . “East Coast braces for invasion of palm-sized venomous spiders capable of flying,” echoes Fox Weather . And The Guardian calls the arachnids “gag-inducing ."

Of course, the scientists who study these animals, which are native to Asia, say such descriptions are misleading at best.

Floyd Shockley , an entomologist and collections manager at the Smithsonian National Museum of Natural History in Washington, D.C., says he’s “mortified” by some of the sensationalist headlines. “There’s no evidence that they’ve made it to New York.”

While it’s true that joro spiders arrived in Georgia in 2014 by unknown means and can survive in the United States, their colonization of the continent isn't exactly imminent. So far, the spiders have been seen in Georgia, the Carolinas, Tennessee, and Oklahoma, with a few tiny satellite populations in places such as Maryland.

What’s more, threat posed by the black-and-yellow arachnids has been routinely exaggerated. (See beautiful photos of spiders.)

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For instance, a recent Gothamist article describes the spiders as having “a body about four inches long and legs that span six to eight inches—about the size of a human hand.”  

“That is completely ridiculous,” says Shockley. “You’d have to stretch this thing out like a medieval torture device to get [its legs] even four inches, let alone six inches.”

What’s more, at this time of the year, every joro spider in the U.S. is no larger than a grain of rice. Adults die each winter, with eggs hatching in the spring and starting the cycle anew.

With so much misinformation afoot, let’s take a look at some of the other claims circulating online.

Can joro spiders fly?

“The way those headlines are written, it makes it sound like they’re the monkeys in the Wizard of Oz,” says David Coyle an assistant professor and invasive species expert at Clemson University.

In truth, none of the large adult joro often pictured in news stories are capable of flight. However, as spiderlings, joro and many other spiders can take to the skies in a common dispersal process called ballooning.

“Right after they hatch, the little hatchlings may be the size of a sesame seed,” says Coyle. “Some of them will get up high and they’ll raise their abdomen. They’ll put a few strands of silk out, and some of them will get carried away by the wind.”  

Yes, just like in Charlotte’s Web . (Related: “This spider web is strong enough for a bird to sit on, a scientific first” )

“I hate to tell people, but every spring, there’s probably thousands of little spiders ballooning over your head, and people have no idea it’s happening.”

As for their "flying" to new states, Shockley says "they have expanded their range, but it's not surprising for an introduced species in 10 years to have moved, you know, a state."

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He adds "we still don't really know anything about how they would [survive] northeastern winters, because obviously they're not there yet."  

Are joro spiders venomous?

This is actually a bit of a trick question, since "spiders are predators and use venom to capture their prey,” says Shockley.

This means that nearly every spider on Earth is venomous, save for two small spider families that have lost the ability to produce venom .

The real question is whether an animal is venomous in a way that could harm people. For U.S. spiders, that is an incredibly small category that includes black widows and brown recluses—not joros, whose venom is non-toxic to people, he says.  

In fact, the few reports of joros biting people suggest it’s like something between the itchy irritation of a mosquito bite and the pain of a bee sting.  

Are joro spiders aggressive?

Despite being relatively large and brightly colored, the joro spider is kind of a pushover.

“Based on my research, they’re really shy,” says Andy Davis , a research scientist at the University of Georgia. “If you leave them alone, they’ll leave you alone, and you can both go about your business.”  

In a 2023 study published in the journal Arthropoda , Davis found that when threatened with a puff of air, native spiders froze for about 96 seconds before resuming their spiderly duties.  

Joro spiders, on the other hand, didn’t move again for more than an hour, making them the most timid arachnids on record. (Read more: “Turns out that huge spider invading the U.S. is incredibly ... shy?” )

“I have held joro spiders dozens of times,” adds Coyle, who has never been bitten. “My kids have held them. They’re typically very docile.”

"They’re just big and scary-looking to a lot of people, but that doesn’t necessarily mean they’re mean or have malevolent or malicious intent.”

The truth about joro spiders  

However unwelcome joro spiders are in the U.S., some experts say it’s time to get used to their new neighbors.

“This is a tough sell,” says Davis, “but maybe, instead of trying to do away with them, people should just maybe sort of learn to live with them. Because their spread is exponential at this point. Like, there’s millions upon millions of them.”

As far as their impact to the environment, it's likely a mixed bag. Joros eat other invasive species, including brown marmorated stink bugs and spotted lanternflies . However, there's also evidence they're outcompeting native spider species .

Even so, Coyle doesn’t see much reason to kill them on sight.

“If it sparks joy, smash them,” he says. “Are you going to do any measurable impact whatsoever to the population? No, you’re not.”

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All About the Venomous Flying Spiders Invading This Summer — and When They're Coming to Your Area

Here's what to know about the Joro spiders arriving this summer, including the states they're expected to invade

wandering spider poisonous

It's a bird! It's a plane! No, it's a parachuting venomous flying spider!

Called Joro spiders , these enormous arachnids have been spreading across North America since the 2010s and are expected to continue making their way up the East Coast this summer.

Georgia was the first state to experience the invasion of the Joro spiders, believed to have made their way from East Asia via shipping trucks or containers around 2013. They are native to China, Japan, Korea and Taiwan.

Whether you have arachnophobia or not, many East Coasters are bracing themselves for the Joro spiders' arrival due to their size and venomous nature (oh, and their ability to "fly"). The invasive species can have up to a 4-inch leg span and possess venom in their fangs.

But before your spider senses start tingling, these arachnids — scientifically titled, Trichonephila clavata (T. clavata) — are completely harmless despite their jarring characteristics. According to  EarthSky , Joro spiders do not pose a threat to humans or pets and "may even be beneficial."

Plus, they don't technically "fly" in the avian sense. "Joro spiders utilize a technique known as ballooning, where they release silk threads into the air, allowing them to be carried by the wind," the New Jersey Pest Control shared .

National Geographic editor Christine Dell’Amore, who's led recent reporting on the Joro spider topic, tells PEOPLE exclusively that we "don't have to worry about them." She assures, "They're not going to sting you. They're not going to bite you."

Read on for what to know about the Joro spider's arrival, including when and where they're expected to invade the United States.

What do Joro spiders look like?

Joro spiders, scientifically called Trichonephila clavata, are described as invasive arachnids native to East Asia. Depending on the spider's gender, their characteristics differ. In contrast to male spiders' smaller size, adult females can grow to the size of one's hand.

Mature females are also vibrant in color in comparison to the males' relatively colorless brown, according to National Geographic . The females have striped legs and abdomens that look like "they've been dipped in a pool of swirling yellow, red, and black paint."

Joro spiders themselves are an exotic sight to see, but their three-dimensional webs are even more spectacular. Adult female spiders can spin strong webs that are yellow-gold in appearance and can span up to 10 feet, according to a study by University of Georgia's Department of Entomology .

When are the Joro spiders expected to arrive in the United States?

Joro spiders spend winter in their egg sacs, emerge in the warmer weather and grow in the months that follow making them easy to spot due to their striking size. Therefore, spotting them depends on where you reside because they haven't yet made their way up the entire East Coast.

In fact, most of the Joro spiders have already "arrived" — but due to their small size when they hatch from their eggs, they aren't as easy to spot compared to their matured appearance.

Which states will be affected by the Joro spiders?

In addition to Georgia, which was the first state graced by their presence around 2014, Joro spiders are expected to work their way up the East Coast with the use of their ballooning technique.

"Spiderlings of this particular group are really good dispersers because of the way they're able to spin a piece of silk. It kind of acts like a parachute, if you will, and gets dragged by the prevailing wind currents," study leader E. Richard Hoebeke , curator of arthropods at the Georgia Museum of Natural History, told National Geographic .

Data from a  peer-reviewed study published in November 2023 showed that "there is an abundance of suitable habitat for T. clavata throughout eastern North America and in some areas in the western part of the continent."

"Those data show that this spider is going to be able to inhabit most of the eastern U.S. It shows that their comfort area in their native range matches up very well with much of North America," David Coyle, one of its authors, shared in a  press release .

As of October 2022, the Joro spider's range spanned across Georgia, South Carolina, North Carolina and Tennessee. There were also reports of the species in Alabama, Maryland, Oklahoma and West Virginia.

José R. Ramírez-Garofalo, an ecologist at Rutgers University's Lockwood Lab, told the   Staten Island Advance in April 2024 that "it is a matter of when, not if," the spiders make their way to New York and New Jersey.

However, National Geographic 's Dell’Amore tells PEOPLE that it's unlikely Joro spiders would make it up to New Jersey and New York from those states by this summer "that quickly."

She explains it can take "several generations for a spider to spread" despite the ballooning behavior the young spiderlings use to travel to different places. "It would take multiple years for them to reach the US Northeast."

The Royal Entomological Society's February 2022 study proved via lab experiment that Joro spiders "can exist in a colder climatic region," but Dell’Amore points out that "there isn't proof in real life yet that they can survive New England winters." She adds, "There's no evidence that they have made it to these states and established populations yet."

Are the Joro spiders dangerous to humans or pets?

Since Joro spiders are capable of living in "human-dominated landscapes," per a study published by the University of Georgia in February 2024, it makes sense why fear and anxiety are prevalent among many ahead of their arrival.

However, Joro spiders pose zero threat to humans or pets. Yes, they have venom in their fangs... like all spiders do!

David Nelson, a professor of biology at Southern Adventist University who has studied the growing range of Joro spiders, told NPR that a bite from one of these creatures might itch at worst or perhaps cause an allergic reaction.

According to a February 2023 University of Georgia study, Joro spiders have an "extremely shy and non-aggressive personality" as a result of an air puff test that caused them to remain "in a frozen state" for over an hour!

EarthSky notes that Joro spiders "may even be beneficial" to us. The site explains, "The spiders eat insects such as stink bugs, which cause crop damage and swarm in homes. They can help control insects without the use of pesticides."

Should Joro spiders be killed?

Whether you're arachnophobic or not, Dell’Amore tells PEOPLE "there's no need to kill spiders when you see them." That goes for Joro spiders, too.

"There are only very few spiders that are actually harmful to people and those are black widows and brown recluse spiders," she points out. "The vast majority of spiders are eating pests and playing important roles in the ecosystem."

In fact, Dell’Amore says spiders "don't want to interact with us." Therefore, she stresses "we should be good neighbors to them, let them do their thing and we do our own thing." She adds, "We can coexist peacefully."

Related Articles

They're big. They're colorful. But Joro spiders aren't nightmare fodder

Joro spiders — invasive, brightly colored, orb-weaving arachnids that have been spreading in the U.S. for the past several years — have captured the public’s interest and horror once again

A large, brightly colored invasive species called the Joro spider is on the move in the United States. Populations have been growing in parts of the South and East Coast for years, and many researchers think it’s only a matter of time before they spread to much of the continental U.S.

But spider experts say we shouldn’t be too worried about them.

“My sense is people like the weird and fantastic and potentially dangerous,” said David Nelsen, a professor of biology at Southern Adventist University who has studied the growing range of Joro spiders. “This is one of those things that sort of checks all the boxes for public hysteria.”

Scientists instead worry about the growing prevalence of invasive species that can do damage to our crops and trees — a problem made worse by global trade and climate change , which is making local environmental conditions more comfortable for pests that previously couldn’t survive frigid winters.

“I think this is one of those ‘canary in the coal mine’ type species where it’s showy, it’s getting a lot of attention,” said Hannah Burrack, professor and chair of the entomology department at Michigan State University. But the shy critter poses little risk to humans. Instead, Burrack said, introduced pests like fruit flies and tree borers can do more damage.

“This is a global concern, because it makes all the things that we do in terms of conservation, in terms of agricultural production, in terms of human health, harder to manage,” she said.

WHAT IS THE JORO SPIDER?

The Joro spider is one of a group of spiders called orb-weavers, named for their wheel-shaped webs. They’re native to East Asia, have bright yellow and black coloring and can grow as long as three inches (8 cm) when their legs are fully extended.

However, they’re pretty hard to spot at this time of year because they’re still early in their life cycle, only about the size of a grain of rice. A trained eye can spot their softball-sized webs on a front porch, or their gossamer threads of golden silk blanketing the grass. Adults are most commonly seen in August and September.

WHERE ARE THEY HEADED?

Scientists are still trying to figure that out, said David Coyle, an assistant professor at Clemson University who worked with Nelsen on a study on the Joro’s range, published last November . Their central population is primarily in Atlanta but expanding to the Carolinas and southeastern Tennessee. A satellite population has taken hold in Baltimore over the last two years, Coyle said.

As for when the species will become more prevalent in the Northeast, an eventual outcome suggested by their research? “Maybe this year, maybe a decade, we really don’t know,” he said. “They’re probably not going to get that far in a single year. It’s going to take a bunch of incremental steps.”

CAN THEY FLY?

The babies can: using a tactic called “ballooning,” young Joro spiders can use their webs to harness the winds and electromagnetic currents of the Earth to travel relatively long distances. But you won’t see fully-grown Joro spiders taking flight.

WHAT DO THEY EAT?

Joro spiders will eat whatever lands in their web, which mainly ends up being insects. That could mean they’ll compete with native spiders for food, but it might not all be bad — a Joro’s daily catch could also feed native bird species, something Andy Davis, a research scientist at the University of Georgia, has personally documented.

As for some observers’ hope that Joro spiders could gobble up the invasive spotted lanternflies destroying trees on the East Coast? They might eat a few, but there’s “zero chance” they’ll make a dent in the population, Coyle said.

ARE THEY DANGEROUS TO HUMANS?

Joro spiders have venom like all spiders, but they aren’t deadly or even medically relevant to humans, Nelsen said. At worst, a Joro bite might itch or cause an allergic reaction. But the shy creatures tend to stay out of humans’ way.

What could one day truly cause damage to humans is the widespread introduction of other creatures like the emerald ash borer or a fruit fly called the spotted wing drosophila that threaten the natural resources we rely upon.

“I try to stay scientifically objective about it. And that’s a way to protect myself from maybe the sadness of it. But there’s so much ecological damage being done all over the world for, for so many reasons, mostly because of humans,” Davis said. “This to me is just one more example of mankind’s influence on the environment.”

The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP’s standards for working with philanthropies, a list of supporters and funded coverage areas at AP.org .

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  1. Brazilian wandering spiders: Bites & other facts

    Brazilian wandering spiders, also known as armed spiders or banana spiders, are some of the most venomous spiders in the world. (Image credit: Joao Paulo Burini via Getty Images) Jump to:

  2. Wandering Spider Facts: Understanding This Species

    In fact, the Brazilian Wandering Spider is the most venomous spider in the New World! In South America, these true spiders are commonly encountered in peoples' homes, supposedly hiding in peoples' shoes, hats, and other clothes. The Brazilian Wandering Spider does not remain on a web, rather, it wanders the forest floor, hence the name."

  3. Wandering spider

    Wandering spiders (Ctenidae) are a family of spiders that includes the Brazilian wandering spiders.These spiders have a distinctive longitudinal groove on the top-rear of their oval carapace similar to those of the Amaurobiidae. They are highly defensive and venomous nocturnal hunters. Wandering spiders are known to hunt large prey, for example hylid species Dendropsophus branneri.

  4. Brazilian Wandering Spider

    The Brazilian Wandering Spider (Phoneutria fera) is an aggressive and highly venomous spider. It was first discovered in Brazil hence its name. However, this genus is known to exist elsewhere in South and Central America. The Brazilian Wandering spider is a member of the Ctenidae family of wandering spiders.

  5. Brazilian Wandering Spider (Phoneutria): Bite, Attacks And Other Facts

    Brazilian wandering spiders are the most poisonous spiders on the planet. They belong to the genus Phoneutria, which consists of a number of spider species. A couple of these species, including Phoneutria nigriventer, P. keyserlingi and P. fera are referred to as Brazilian wandering spiders.

  6. Phoneutria nigriventer

    Phoneutria nigriventer is a species of medically significant spider in the family Ctenidae, found in the Southern Cone of South America (Brazil, Uruguay, Paraguay, and Argentina). Along with other members of the genus, they are often referred to as Brazilian wandering spiders.. Its bite can cause severe symptoms, including increased pulse, blood pressure, and respiratory rate; extraordinary ...

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  8. Phoneutria

    Phoneutria is a genus of spiders in the family Ctenidae.They are mainly found in northern South America, with one species in Central America. Members of the genus are commonly referred to as Brazilian wandering spiders. Other English names include armed spiders (armadeiras in Brazilian Portuguese) and banana spiders (a name shared with several others).

  9. Brazilian Wandering Spider Bite: Is It Poisonous? What You Need to Know

    The Brazilian wandering spider, native to South and Central America, is renowned for its potent venom, making it one of the world's most venomous spiders. While their bite can lead to severe symptoms, including pain, blurred vision, and even death, timely medical intervention can mitigate these effects.

  10. Wandering spider

    Wandering spider, any member of the arachnid family Ctenidae (order Araneida), a small group of large venomous spiders of mainly tropical and subtropical regions, commonly found on foliage and on the ground. Their first two legs are armed with strong bristles on the lower side.

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    Brazilian Wandering Spider Size. Being quite large and impressive compared to most arachnids, adult Brazilian Wandering Spiders can reach a leg span of up to 7 inches (18 cm). The body size excluding the legs can be up to 2 inches (5 cm). Their size contributes to their intimidating presence.

  12. Brazilian Wandering Spiders (Phoneutria): Facts ,Identifications & Pictures

    Ecological Importance and Behavior of the Brazilian Wandering Spider. The Brazilian Wandering Spider, scientifically known as Phoneutria, stands out not just because of its reputation as one of the world's most venomous spiders, but also due to its ecological significance and unique behavior. Natural Predator: Despite their fearsome ...

  13. Brazilian Wandering Spider: Size, Bite, Diet and Other Facts

    The Brazilian Wandering Spider is a venomous arachnid with a fearsome reputation. This South American rainforest dweller packs a powerful punch, but don't let its nickname "banana spider" fool you - they're active hunters, not web-spinners. Despite their size and venom, bites are uncommon as they're typically shy.

  14. Venomous Spiders: What Are Some Of The World's Deadliest Spiders?

    The Brazilian wandering spider is extremely toxic to humans and is considered to be one of the world's most venomous spiders. This species injects a powerful neurotoxin that causes breathing problems, respiratory paralysis, an irregular heartbeat, and long-lasting (and excruciatingly painful) erections in men.

  15. 9 of the World's Deadliest Spiders

    Phoneutria are poisonous to humans, and they are considered to be the deadliest of all the world's spiders. Their venom is toxic to the nervous system, causing symptoms such as salivation, irregular heartbeat, and prolonged, painful erections (priapism) in men.

  16. Brazilian Wandering Spider

    By tarikregad August 17, 2023 August 17, 2023. Brazilian Wandering Spider, scientifically known as Phoneutria, emerges as a captivating enigma in the realm of arachnids. Renowned for its formidable reputation as one of the world's most venomous spiders, Phoneutria embodies a plethora of intriguing traits that have captured the curiosity of ...

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  18. Brazilian Wandering Spider: Care, Food, Habitat & Preventions

    The Brazilian wandering spider, scientifically known as Phoneutria, Maximilian Perty kickstarted the Phoneutria genus in 1833. The name comes from the Greek word φονεύτρια, which means "murderess" and falls under the Animalia kingdom, Arthropoda phylum, and Arachnida class. Within Arachnida, it is classified in the order Araneae ...

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    "The most venomous species (Sydney funnel-web spiders, Brazilian wandering spiders) don't kill or impact that many people," Linda Rayor, a behavioral ecologist at Cornell University who focuses on ...

  20. The World's Most Venomous Spider: The Brazilian Wandering Spider

    The Brazilian Wandering Spider is found in the rainforests of South America. These rainforests are the world's largest and most biodiverse terrestrial ecosystems, covering an area of approximately 6.7 million square kilometers. The spider is striking, with a shiny brown or black body covered in short fine hairs.

  21. Can a Bite From a Brazilian Wandering Spider Cause a Four-Hour Erection

    Venomous Animals and Their Venoms: Venomous Invertebrates. Elsevier, 2013. Nunes, K. P., et al. "Tx2-6 Toxin of the Phoneutria Nigriventer Spider Potentiates Rat Erectile Function."

  22. Top 11 Largest Spiders in the World

    Like many other spiders, males live to be about four or five years, while female spiders live to be around 20 years. The Colombian Giant Tarantula is a bit more timid than others, typically burrowing or fleeing at a threat. Brazilian Wandering Spider (Phoneutria fera) Venomous wandering spider (Phoneutria fera).

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  25. Are Joro Spiders Venomous? Bug Experts Explain the Flying Spiders

    This is a little complicated. Joro spiders are venomous, meaning they make venom, Ramírez-Garofalo says. But all spiders are venomous, he points out. "Joro spiders are technically venomous ...

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    June 06, 2024. Joro spiders are in the news again, and judging by the headlines, everyone is doomed. "Giant venomous flying spiders… heading to New York area," says CBS News. "East Coast ...

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    A large, female Joro spider on her web. getty. Joro spiders, scientifically called Trichonephila clavata, are described as invasive arachnids native to East Asia. Depending on the spider's gender ...

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