wandering spider brazil

Brazilian wandering spiders: Bites & other facts

Brazilian wandering spiders don't build webs but crawl on the forest floor at night in search of prey, which they kill with neurotoxic venom.

Classification/taxonomy

Size & characteristics, bites and venom, additional resources.

Brazilian wandering spiders are aggressive spiders that belong to the genus Phoneutria, which means "murderess" in Greek.

These critters, also known as armed spiders or banana spiders, are some of the most venomous spiders on Earth. Their large mouthparts, or chelicerae, inflict painful bites loaded with neurotoxic venom that can be deadly to humans — especially children — although in most cases immediate medical care can prevent death with antivenom, according to a 2018 study in the journal Clinical Toxinology in Australia, Europe, and Americas .

Brazilian wandering spiders are frequently listed among the deadliest spiders in the world . They were named the world's deadliest spiders multiple times by Guinness World Records, although the current record-holder is the male Sydney funnel-web spider ( Atrax robustus ). But "classifying an animal as deadly is controversial," Jo-Anne Sewlal, an arachnologist at the University of the West Indies in Trinidad and Tobago, previously told Live Science. Each bite is unique, and the damage it causes depends on the amount of venom injected, Sewlal said. 

Jo-Anne Sewlal was a noted arachnologist from Trinidad and Tobago. While completing her PhD, she received the National Institute of Higher Education, Research, Science and Technology (NIHERST) 2012 Award for Excellence in Science and Technology for Junior Scientist. In 2013, She received a doctorate in zoology from the University of the West Indies. She discovered several species of spiders in her home country, surveyed the arachnids across several countries the Caribbean and appeared as an expert on the topic on The Science Channel. She died of an allergic reaction in January 2020.

There are nine species of Brazilian wandering spider, all of which are nocturnal and can be found in Brazil. Some species also can be found throughout Central and South America, from Costa Rica to Argentina, according to a 2008 article in the journal American Entomologist . Study author Richard S. Vetter , a research associate in the department of entomology at the University of California, Agriculture and Natural Resources, wrote that specimens of these powerful arachnids have been mistakenly exported to North America and Europe in banana shipments. However, Vetter noted, in many cases of cargo infestation, the spider in question is a harmless banana spider (genus Cupiennius ) that is misidentified as a Phoneutria . The two types of spiders look similar.

The taxonomy of Brazilian wandering spiders, according to the Integrated Taxonomic Information System (ITIS) , is:

Kingdom : Animalia 

Subkingdom : Bilateria 

Infrakingdom : Protostomia 

Superphylum : Ecdysozoa 

Phylum : Arthropoda 

Subphylum : Chelicerata 

Class : Arachnida 

Order : Araneae 

Family : Ctenidae 

Genus : Phoneutria  

• Phoneutria bahiensis
• Phoneutria boliviensis
• Phoneutria eickstedtae
• Phoneutria fera
• Phoneutria keyserlingi
• Phoneutria nigriventer
• Phoneutria pertyi
• Phoneutria reidyi
• Phoneutria depilata , according to a 2021 study published in the journal ZooKeys , which found that Phoneutria boliviensis actually included two separate species from different habitats. 

Brazilian wandering spiders are large, with bodies reaching up to 2 inches (5 centimeters) and a leg span of up to 7 inches (18 cm), according to the Natural History Museum in Karlsruhe, Germany. The species vary in color, though all are hairy and mostly brown and gray, although some species have lightly colored spots on their abdomen. Many species have bands of black and yellow or white on the underside of the two front legs, according to the University of Florida . 

These arachnids "are called wandering spiders because they do not build webs but wander on the forest floor at night, actively hunting prey," Sewlal told Live Science in an interview conducted in 2014, before her death. They kill by both ambush and direct attack.

They spend most of their day hiding under logs or in crevices, and come out to hunt at night. They eat insects, other spiders and sometimes, small amphibians, reptiles and mice. 

Research into one species of Brazilian wandering spider, Phoneutria boliviensis , revealed that these spiders eat a mix of arthropods and reptiles. DNA metabarcoding, a technique that examines the DNA and RNA in a sample, of the guts of 57 spiders identified 96 prey species, including flies, beetles, butterflies, moths, grasshoppers, locusts and crickets, according to research from the University of Tolima and the University of Ibagué in Colombia . Some of the female spiders also ate lizards and snakes.

While their bites are powerful and painful, "their bites are a means of self-defense and only done if they are provoked intentionally or by accident," Sewlal said.

When Brazilian wandering spiders feel threatened, they often assume a defensive position by standing on their hind legs and stretching out their front legs to expose their fangs, according to the 2018 study in Clinical Toxinology in Australia, Europe, and Americas. This posture is sometimes accompanied by side-to-side movements. The spiders can also jump distances up to 1.3 feet (40 cm). 

In the Brazilian wandering spider, just as in most spider species, the female is larger than the male. Males approach females cautiously when attempting to mate, according to the biology department at the University of Wisconsin-La Crosse . Males perform a dance to get females' attention, and males often fight each other over the female. The female can be picky, and she often turns down many males before choosing a mating partner. Once she does pick one, the male needs to watch out; females often attack the males once copulation is finished.

The female then can store the sperm in a separate chamber from the eggs until she is ready to fertilize them. She will lay up to 1,000 eggs at a time, which are kept safe in a spun-silk egg sac.

Brazilian wandering spiders typically live for one or two years.

Brazilian wandering spiders' venom is a complex cocktail of toxins, proteins and peptides, according to the Natural History Museum in Karlsruhe, Germany. The venom affects ion channels and chemical receptors in victims' neuromuscular systems.

After a human is bitten by one of these spiders, they may experience initial symptoms such as severe burning pain at the site of the bite, sweating and goosebumps, Sewlal said. Within 30 minutes, symptoms become systemic and include high or low blood pressure , fast or a slow heart rate , nausea, abdominal cramping, hypothermia, vertigo, blurred vision, convulsions and excessive sweating associated with shock. People who are bitten by a Brazilian wandering spider should seek medical attention immediately.

Their venom is perhaps most famous for triggering painful and long-lasting erections . For that reason, in a 2023 study, scientists reported that they were testing the venom in humans as a potential treatment for erectile dysfunction in those for whom Viagra didn't work.

However, these bites are rare, and envenomations, or exposure to these toxins from a spider bite, are usually mild, Vetter said. For instance, a 2000 study in the journal Revista do Instituto de Medicina Tropical de São Paulo found that only 2.3% of people with bites who came to a Brazilian hospital over a 13-year period were treated with antivenom. (The other bites did not contain enough venom to require it.) Most of the bites were from the species P. nigriventer and P. keyserlingi in eastern coastal Brazil. About 4,000 bites reportedly happen each year in Brazil, but only 0.5% of those cases are severe, according to the 2018 study. Meanwhile, 15 deaths have been attributed to Phoneutria in Brazil since 1903, the 2018 study reported. 

"It is unlikely that the spider would inject all of its venom into you, as this venom is not only needed as a means of defense but to immobilize prey," Sewlal said. "So if it did inject all of its venom, it [would] have to wait until its body manufactured more before it could hunt." That would also leave the spider vulnerable to being attacked by predators.

Furthermore, Sewlal pointed out that venom production requires a lot of a spider's resources and time. "So if the spider were to attack frequently and use up all of its venom, it [would] be safe to assume that it has a ready food supply to replace the energy and resources used. This situation does not exist in the wild."

• Learn more about Brazilian wandering spiders from the University of Wisconsin-La Crosse .
• Read about several species of Brazilian wandering spiders, including several images of the arachnids at the University of Florida .
• Find a spider in your bananas? It may or may not be a deadly species, according to the University of California, Riverside .

This article was originally published on Nov. 20, 2014. 

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Jessie Szalay is a contributing writer to FSR Magazine. Prior to writing for Live Science, she was an editor at Living Social. She holds an MFA in nonfiction writing from George Mason University and a bachelor's degree in sociology from Kenyon College. 

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• Sascha Pare Trainee staff writer

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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 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.

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

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

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.

Understanding the Wandering Spider: Quick Essential Facts

Wandering spiders are a group of venomous arachnids found primarily in South America.

Among these, the Brazilian wandering spider is particularly known for its potent venom and unique behavior. They are often referred to as “banana spiders” due to their frequent encounters with humans in banana plantations.

As a reader, you might be interested in learning more about these fascinating creatures, including their habitat, hunting techniques, and the effects of their venom.

In this article, we will delve into the world of wandering spiders and provide you with all the essential information to satisfy your curiosity.

Scientific Classification and Naming

The wandering spider belongs to the genus Phoneutria , which is a part of the Ctenidae family.

These spiders are known for their potent venom and aggressive behavior. Here is the scientific classification of the wandering spider:

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

Within the genus Phoneutria, two species are particularly noteworthy: Phoneutria fera and Phoneutria nigriventer, also known as P. nigriventer . These spiders are primarily found in South America and other tropical regions.

Phoneutria fera and P. nigriventer differ in some aspects. Let’s compare their features using a table:

Some key characteristics of the wandering spiders in the genus Phoneutria include:

• Potent venom that can be dangerous to humans
• Nocturnal hunters and are active at night
• Equipped with long, spiny legs for capturing prey
• Aggressive defenders of their territory

By understanding the scientific classification and differences between Phoneutria species, you can better appreciate the diversity and fascinating biology of these wandering spiders.

Identification and Appearance

Color and size.

The wandering spider, also known as the banana spider, has a distinctive appearance that can help you easily identify it in the wild.

They usually have a combination of hairy brown and black colors on their body. Their size can vary, but they are generally considered large spiders. Their size can range from 1 to 2 inches in body length.

When it comes to wandering spider’s leg span, these creatures can have an impressive reach. Their leg span can extend up to 5-6 inches.

Some key characteristics of a wandering spider’s legs include:

Habitat and Distribution

Wandering Spiders are known to inhabit various environments, including rainforests and tropical forests.

These spiders can adapt to different habitats based on their needs and availability of food sources. They prefer warm and humid places, as these conditions suit their growth and reproduction.

Geographical Coverage

Wandering spiders are found in Central and South America .

They live in forests from Costa Rica to Argentina, including Colombia, Venezuela, The Guianas, Ecuador, Peru, Bolivia, Brazil, Paraguay, and Northern Argentina.

They may also be present in some parts of the United States, particularly in the northern part of southern America.

However, they don’t inhabit countries like Australia. In summary, the Wandering Spider is mostly prevalent in the following areas:

• South America
• Central America
• Southern parts of the United States

Types of Wandering Spiders

Here’s a brief description of the major types of wandering spiders.

Brazilian wandering spiders

Also known as armed or banana spiders, these spiders are nocturnal and don’t make webs.

They are known to have been transported outside of South America in banana shipments.

Phoneutria nigriventer

These spiders contain neurotoxins that can cause cerebral changes and breakdown of the blood-brain barrier .

Their venom is medically significant and has been used in manufacturing drugs. Their bites may be fatal to children.

Ctenus captiosus

Also known as the Florida false wolf spider or tropical wolf spider, this species is found in the United States.

Some species of these spiders are large and scary-looking, but they’re only mildly venomous. Their venom is comparable to a bee sting.

Other types of wandering spiders include: Acantheis, Acanthoctenus, Africactenus, and Afroneutria.

Behavior and Diet

Aggression level.

Wandering spiders, as their name suggests, are known for their aggressive behavior .

While they won’t attack without provocation, if they feel threatened, they will not hesitate to defend themselves.

This is especially true during mating season.

Prey and Predators

In their natural habitat, wandering spiders primarily feed on insects and small vertebrates, such as:

• Insects like ants and moths
• Small amphibians

This diverse diet allows them to thrive in various ecosystems.

However, they are not top predators, as their natural predators include larger birds, mammals, and other spiders.

Nocturnal Activities

Wandering spiders are nocturnal creatures , which means they are active during the night.

During the day, they remain hidden in their retreats, often made from rolled-up leaves or small crevices.

At night, they leave their hiding spots to search for prey using their strong hunting skills.

Venom and Its Effects

Composition of venom.

The venom of the wandering spider is a complex mixture containing several toxic components.

Its main component is a potent neurotoxin, which can have severe effects on your nervous system 1 . Here’s a brief overview of its composition:

• Neurotoxins

Symptoms and Severity

A wandering spider’s venomous bite can cause a wide range of symptoms, depending on the severity of envenomation. These symptoms may include 2 :

• Mild to moderate pain
• Redness and swelling at the bite site
• Irregular heartbeat
• Difficulty breathing
• Blurred vision
• High blood pressure

Some severe cases may result in life-threatening complications, such as respiratory failure or even death 2 .

Medical Treatment and Antivenom

If bitten by a wandering spider, it’s crucial to seek immediate medical attention. Treatment often involves the following steps:

• Cleaning and immobilizing the affected area
• Monitoring and managing the symptoms
• Administering antivenom if it’s available and appropriate, depending on the severity of envenomation 3

Antivenom is specific to the venom of the wandering spider and can help neutralize its effects.

However, the availability of antivenom may be limited in some regions 3 .

Always remember that prevention is better than cure: learning how to identify and avoid wandering spiders is the best way to stay safe.

Reproduction and Mating

Mating ritual.

When it’s time for reproduction, the wandering spider undergoes an intriguing mating ritual.

The male spider performs a dance to attract the female by displaying his brightly colored legs and vibrating his body.

During the process, the male also produces a sperm web and transfers his sperm to the female’s reproductive organs using his pedipalps.

Egg Sacs and Offspring

After the mating process, the female wandering spider will create an egg sac to protect her eggs.

The sac consists of silk and can hold hundreds of eggs. She then attaches it to a safe hiding place, usually against a protective surface or within a secure web.

The female often guards the egg sac to ensure the protection of her offspring until they hatch.

Once the spiderlings hatch, they are known to be highly independent.

They disperse quickly and start their own journey, fending for themselves soon after emerging from the egg sac.

As they grow, they’ll go through a series of molts before reaching adulthood and beginning their own reproductive cycle.

Danger and Defense Mechanisms

The Wandering Spider is known to be one of the most dangerous spiders in the world.

Although they can potentially kill humans, fatalities are rare due to their reluctance to bite.

Oddly enough, their venom can cause an involuntary erection in men, alongside other painful symptoms.

Here are some ways the Wandering Spider protects itself and displays its dangerous nature:

• Fangs : These spiders are equipped with strong, sharp fangs that can easily pierce human skin, allowing them to inject their venom with ease.
• Venom : Their venom is potent and can cause severe pain, inflammation, and other adverse effects. In rare cases, it can even lead to death.

While interacting with Wandering Spiders, be cautious and observe them from a safe distance.

Knowing their defense mechanisms will help you respect their space and avoid any unpleasant encounters.

Remember, it’s essential to be informed and aware when dealing with these fascinating, yet dangerous creatures.

Comparison with Other Dangerous Spiders

Comparison to black widow.

The black widow spider is notorious for its potent venom, but the wandering spider has a stronger venom overall.

Both spiders are capable of causing severe symptoms, but the black widow’s venom is primarily neurotoxic, affecting your nervous system.

In contrast, the wandering spider’s venom can cause both neurotoxic and cytotoxic effects, potentially damaging your nerves and cells.

• Potent neurotoxic venom
• Red hourglass marking
• Stronger venom (neurotoxic and cytotoxic)
• No distinct marking

Comparison to Brown Recluse

The brown recluse spider is known for its necrotic venom that can lead to tissue damage and sometimes requires medical intervention.

While both the brown recluse and wandering spider can produce venomous bites, wandering spiders are considered more dangerous due to the potency of their venom and the severity of their bite symptoms.

• Necrotic venom
• Dark violin-shaped marking

Comparison to Wolf Spider

Wolf spiders are frequently mistaken for more dangerous spiders due to their size and appearance.

Although they can bite, their venom is not particularly potent and generally only causes mild itching, redness, and swelling.

In comparison, the wandering spider’s venom is far more dangerous, and its bite can result in serious symptoms, requiring immediate medical attention.

• Large and hairy
• Smoother appearance

Comparison to Sydney Funnel-Web Spider

The Sydney funnel-web spider is another highly venomous spider known for its potentially lethal bites.

While both spiders possess powerful venom, the wandering spider has a broader range of symptoms due to the combination of neurotoxic and cytotoxic effects.

In conclusion, wandering spiders are more dangerous than wolf spiders but their venom’s effects are more varied compared to black widows, brown recluses, and Sydney funnel-web spiders.

Be cautious around these spiders and seek medical help if bitten.

Interesting Facts and Guinness World Records

The Wandering Spider, also known as the Brazilian Wandering Spider, is a fascinating creature that has caught the attention of many.

They belong to the genus Phoneutria , which means “murderess” in Greek, giving you an idea of their potency. Let’s explore some interesting facts about this spider and its place in the Guinness World Records.

First, you might be curious about their venom. The Wandering Spider is known for having one of the most potent venoms among spiders.

In fact, it holds the Guinness World Record for the most venomous spider. Their venom contains a potent neurotoxin that can cause severe symptoms, including difficulty breathing, high blood pressure, and intense pain.

Apart from their venom, their behavior is also quite intriguing. These spiders are called “wandering” because they are known for actively hunting their prey rather than spinning webs to catch them.

They are mostly nocturnal creatures and, during the day, can be found hiding in logs or dark crevices.

Here are a few more notable characteristics of the Wandering Spider:

• Females are larger than males, with a body length of up to 1.6 inches (4 cm).
• They have eight eyes, arranged in two rows, which help them in hunting.
• The Wandering Spider is primarily found in Central and South America, particularly in Brazil.
• They are known to show aggression when threatened.

While the Wandering Spider is a marvel of the arachnid world, it’s essential to keep a safe distance from them due to their venomous nature.

However, their unique characteristics and record-breaking venom potency make them a fascinating subject for those interested in the natural world.

Prevention and Safety Measures

To protect yourself from wandering spiders, there are some simple safety measures you can take.

Firstly, be cautious in areas where these spiders may live, such as dark and warm spaces. For example, avoid reaching into crevices or lifting piles of wood without inspecting them first.

Always wear appropriate shoes when outdoors, particularly in wooded or grassy areas. This can help prevent bites on your feet or ankles.

Reduce the risk of wandering spiders entering your home by sealing gaps and cracks. This minimizes the chance of the spiders finding a way inside.

Regularly clean your living spaces, paying special attention to dark and hidden areas. By maintaining a clean environment, you’ll discourage wandering spiders from making themselves at home.

When out in nature, avoid disturbing spider habitats like webs or egg sacs. This can prevent agitating wandering spiders, reducing your chance of accidental encounters.

Remember, wandering spiders can be dangerous, but by taking these precautions, you can significantly reduce your risk of encountering them or being bitten. Stay safe and always be aware of your surroundings.

In summary, wandering spiders, particularly those in the genus Phoneutria, are a group of venomous arachnids predominantly found in Central, South America and parts of Southern United States.

These spiders, including the Brazilian wandering spider, are known for their potent venom, nocturnal hunting habits, and aggressive defense mechanisms.

Their venom, containing neurotoxins and other components, can cause severe symptoms in humans, making them one of the most dangerous spider species.

Despite their fearsome reputation, fatalities are rare, and they play a vital role in their ecosystems.

It’s important to respect their space and take preventive measures to avoid encounters. Understanding these spiders’ behavior, habitat, and characteristics can help in appreciating their role in nature while ensuring safety.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2857337/ ↩

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3851068/ ↩ ↩ 2

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6560916/ ↩ ↩ 2

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about wandering spiders. Scroll down to have a look at some of them.

Letter 1 – Wandering Spider from Ecuador

Hi Michele, There is a resemblance to the Dolomedes Fishing Spiders, and finding it near a river lends credence to that possibility. Eric Eaton noticed this posting and has this to say: ” Ok, the spiders from Ecuador and Costa Rica: They are most likely NOT wolf spiders, but wandering spiders, 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.”

Update:  May 14, 2013 We now have a confirmation that this is a Wandering Spider, Phoneutria fera , and it is a dangerous species.  See Encyclopedia Britannica and Animal Corner .

Letter 2 – Brazilian Wandering Spider: Most Venomous Animal

Hi Martin, We are happy you were able to write to us after your encounter with this Brazilian Wandering Spider and are thrilled to be able to post your story and photos to our site. We started to research, and our first hit has a different species name. Phoneutria fera is described as: “The Brazilian Wandering Spider is not for the ‘pet keeper’. Brazilian Wandering Spiders are extremely fast, extremely venomous, and extremely aggressive. These large and dangerous true spiders are ranked among the most venomous spiders known to man. 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.” Our favorite information on Wikipedia is that Phoneutria is Greek for “murderess”. Here is one final tidbit about the effect of the bite of the Brazilian Wandering Spider on the human male .

Letter 3 – Possibly Wandering Spider from Ecuador

Dear Mike, This is really an interesting Spider, but other than to say it appears to be a hunting spider that does not build a web to entrap prey, we aren’t sure about its identity.  Many hunting spiders can jump quite well.  It looks very much like the spider in a posting in our archives, also from Ecuador, that we identified as possibly a Wandering Spider in the genus Phoneutria, a venomous and potentially dangerous genus .  The spotted legs on your individual look like the spotted legs on an individual in an image on Wikipedia of a Wandering Spider in the genus Phoneutria .  There are many images of Brazilian Wandering Spiders on Primal Shutter and we believe that might be a correct identification for your individual.

Thank you for the information.  After reading more about the spider, I’m glad it didn’t jump! Mike

Letter 4 – Possibly Wandering Spider from Ecuador

Dear Carl, We believe, though we are not certain, that this might be a Wandering Spider in the genus Phoneutria, and you may read more about Wandering Spiders on the Museum für Naturkunde Karlsruhe website where it states:  “There is no doubt that the venom of some of the species is quite potent for mammals, including humans.”  We eagerly welcome additional opinions on this identification.  Perhaps Cesar Crash of Insetologia can provide something.  In the future, please submit a single species per submission form as it makes it extremely difficult for us to categorize postings with multiple species.

Letter 5 – Wandering Spider from Belize

Hi Karl, Thanks for allowing us to post your excellent image of a Wandering Spider, Cupiennius salei .  The species is pictured on iNaturalist .

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 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.

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8 comments . leave new.

Hi Michele, I am an Ecuadorian scientist and specialized on spiders, I would like to find one like yours, I can say that, almost without doubt, you found the Phoneutria itself, it is the Phoneutria fera, look at this picture: http://www.google.com/imgres?imgurl=http://4.bp.blogspot.com/-bFH9qzT0F7U/T_2sZuk6xAI/AAAAAAAAAGY/8jnMVcPOcNI/s1600/phoneutria_fera2.jpg&imgrefurl=http://rangerbaiano.blogspot.com/2012/07/animais-peconhentos-e-venenosos.html&usg=__iCWEz7S86xub6RAyvXTER6HBaco=&h=864&w=834&sz=215&hl=es-419&start=6&zoom=1&tbnid=jjOROVO9h-vKXM:&tbnh=145&tbnw=140&ei=99eRUY6xKo2K9QTLvYCoDQ&prev=/search%3Fq%3Dphoneutria%2Bfera%26sa%3DN%26hl%3Des-US%26sout%3D1%26tbm%3Disch%26prmd%3Divns&itbs=1&sa=X&ved=0CDYQrQMwBQ Can you see the similarities?, unfortunately the spider might be in a better life today 🙂 Another thing, when you want identifications you should take a picture in front, the under part, and the upper part, as well as some characteristics about behaviour like how they react when you approach. The Phoneutria is a very agressive one.. best wishes, bye.

Hi Miguel, Thanks so much for the comment. This is a seven year old posting and we did not have the ability to post comments when it was originally posted online. We have made an update on What’s That Bug? and your comment is greatly appreciated.

Ah, there is also needed the size and the picture of its face so we can see the eye arrangement, depending on that it could also be pisauridae, but I stay in Ctenidae..

This is a female Cupiennius sp. wandering spider.

Perhaps surprisingly, this ubiquitous large spider of the Mindo area appears to be undescribed to species level.

Although one is indeed best advised to exercise caution in the presence of large ctenids, members of the genus Cupiennius are not known to be dangerously venomous (Barth, 2002). By way of confirmation, my girlfriend, Shannon Bowley, managed to be bitten by a mature female of this Mindo species in 2013 – she felt only mild effects, equivalent to a bee sting.

Thanks for this valuable information.

I’m planning a trip to Ecuador and I’m fearing these spiders. Do they get in houses? Any tips to keep them out, so I can sleep at night?

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Brazilian wandering spider | bite,Size, Habitat, & Facts

Brazilian wandering spider.

brazilian wandering spider size

Their body length ranges from 17 to 48 mm (43⁄64 to 1+57⁄64 in). Phoneutria are impressive spiders reaching body sizes up to 3.5 centimeters and leg spans up to 15 centimeters. They are nocturnal, hunting at night, and hiding in dark places during the day.

Wandering spider bite

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 pain; penile erection that lasts for several hours; and, in several documented cases, death.

Phoneutria spp.  is actually a genus with five known similar species whose members are highly venomous. They include some of the relatively few species of spiders that present a threat to human beings. The Brazilian Wandering Spider (Phoneutria fera) can grow to have a leg span of up to 4-5 inches.

Wandering spider, (family Ctenidae), any member of the family Ctenidae (order Araneida), a small group of large spiders of mainly tropical and subtropical regions, commonly found on foliage and on the ground.

The Brazilian wandering spiders, Phoneutria fera and P. nigriventer, are sometimes also referred to as banana spiders because they are frequently found on banana leaves. They have an aggressive defense posture, in which they raise their front legs straight up into the air. Phoneutria are venomous, and their venom is toxic to the nervous system, causing symptoms such as salivation, irregular heartbeat, and prolonged painful erections (priapism) in men. Scientists are investigating the venom of P. nigriventer as a possible treatment for erectile dysfunction.

These spiders are notorious both due to their toxic venom, and because they are not reluctant to attack people who appear threatening.

Of the five species known, P. nigriventer and P. fera most frequently receive mention in mass-media publications. P.nigriventer species are responsible for most cases of venom intoxication in Brazil because this species is commonly found in highly populated areas of Brazil, namely the South-eastern states: São Paulo, Minas Gerais, Rio de Janeiro and Espírito Santo.The P. fera is native to the northern portion of South America, especially the Brazilian Amazônia, Venezuela and French Guiana.

Brazilian wandering spider BITES AND VENOMB

　　razilian wandering spiders’ venom is a complex cocktail of toxins, proteins and peptides, according to the Natural History Museum in Karlsruhe, Germany. The venom affects ion channels and chemical receptors in victims’ neuromuscular systems.

　　After a human is bitten by one of these spiders, he or she may experience initial symptoms such as severe burning pain at the site of the bite, sweating and goosebumps, Sewlal said. Within 30 minutes, symptoms become systemic and include high or low blood pressure, fast or a slow heart rate, nausea, abdominal cramping, hypothermia, vertigo, blurred vision, convulsions and excessive sweating associated with shock. People who are bitten by a Brazilian wandering spider should seek medical attention immediately.

Recent studies suggest that these spiders only inject venom in approximately one-third of their bites and may only inject a small amount in another third. However, research in this area is hindered by the difficulty of identifying particular subspecies. Thus the effects of the bites from these spiders are hard to predict when based on sketchy information or if the spider has not been identified definitively. 

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

he Phoneutria fera and nigriventer  are the two most commonly implicated as the most virulent of the Phoneutria spiders. The Phoneutria not only has a potent neurotoxin, but is reported to have one of the most excruciatingly painful envenomations of all spiders due to its high concentration of serotonin.  

Brazilian Wandering Spiders are extremely fast, extremely venomous, and extremely aggressive and are ranked among the most venomous spiders known to man. 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. It does not remain on a web, rather, it wanders the forest floor, which is how it got its name.

The Brazilian Wandering Spider has another name – the  Banana Spider  and it was given this name  because there have been cases where these spiders unintentionally appeared on banana boats heading for the United States.

​　　Brazilian Wandering Spider: One Of The World’s Most Venomous Spiders May Be Lurking In Your Bananas

　　Meet the Brazilian wandering spiders in the genus Phoneutria, also referred to as the armed spiders or the banana spiders. The members of this group have one of the most dangerous bites of any spider species on Earth and they have been classified as the world’s most venomous spider many times.

　　What Are The Effects Of A Brazilian Wandering Spider Bite?

　　Brazilian wandering spiders often make the news because of the unusual symptoms caused to humans after being bitten by one.

　　A 2023 study in Frontiers In Molecular Biosciences suggested there were around 4,000 cases of people being bitten by Phoneutria nigriventer in Brazil each year. Their venom affects the nervous system, causing double vision, salvation, irregular heartbeat – and even prolonged painful erections, known as priapism. In fact, because of this, their venom is being explored as a possible treatment for erectile dysfunction conditions.

　　Can A Brazilian Wandering Spider Bite Kill You?

　　The neurotoxin PhTx3 is to blame for these symptoms, and according to the Independent, a wandering spider bite can reportedly be fatal in as little as 60 minutes. However, an effective anti-venom is usually enough to save those affected. A study into Phoneutria boliviensis in 2019 suggested that the species had adapted its venom to catch vertebrates as opposed to lizards and amphibians, which might explain why the venom is so toxic to humans.

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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.

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 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.

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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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.

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

 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 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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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!

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.

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.

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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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

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.

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.

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.

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

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.

Other Spiders in this Family

Wandering spiders.

Phoneutria depilata

Phoneutria boliviensis

Phoneutria fera

Phoneutria nigriventer

Southeastern Wandering (Anahita punctulata)

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Brazilian wandering spider: Where are they from and how deadly are they?

One was found in a bunch of supermarket bananas in london, article bookmarked.

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The world’s most venomous spider has been delivered to a south London home in a bunch of bananas.

Specialists were called in to trap the Brazilian wandering spider, which ripped its leg off in a bid to escape and left an egg sac full of thousands of baby spiders behind.

The family who received the deadly arachnid in their Waitrose online shop told the Mail on Sunday they were “too traumatised to remain in the house”, while the supermarket apologised for the “distressing” incident.

It was not the first time a Brazilian wandering spider made the long journey to the UK.

In 2005, a chef in Somerset was bitten by a stowaway that had been hiding in bananas delivered to his pub.

He was saved by anti-venom administered after a nearby zoo identified the arachnid from a picture he took on his phone before passing out.

The spiders and their eggs have also been found in bananas from a Tesco in Essex and One Stop in Staffordshire.

Where are they from?

Fortunately, it is very rare to find Brazilian wandering spiders in the UK or anywhere outside their natural habitat in South America.

They live in the forests of Costa Rica, Columbia, Peru, Brazil, and Paraguay and gain their name from the habit of moving across jungle floors at night in search of food.

In the day, they like hiding in places that are dark and moist and are known to favour piles of wood, garages, cupboards, shoes and even heaps of clothes.

The apparent tendency to hide in banana bunches – like in the latest incident – has given them the nickname “banana spider”.

Their scientific name translates as “murderess” in Greek and they are also known as the “armed spider”, because of their unusual attacking stance, and “horse stinger”.

How deadly is it?

The Guinness Book of World Records has named it the most venomous spider in the world for possessing the most active neurotoxic venom of any living spider.

The toxin PhTx3 causes extreme pain, swelling, paralysis, skin cell destruction, fatal breathing complications, heart attacks and painful erections (priapism) in men lasting up to four-hours.

Victims of a Brazilian wandering spider bite can reportedly be killed in an hour.

But few deaths occur because an effective anti-venom is available in Brazil and Guinness claims that people are killed, it is usually in children under the age of seven.

Scientists have reportedly considered investigating the use of the deadly venom as a possible ingredient for drugs treating erectile dysfunction.

What do Brazilian wandering spiders look like?

There are eight known species, with the most dangerous being the Phoneutria fera and the Phoneutria nigriventer.

All vary slightly in appearance but are known for their size, with a leg span of up to 15 cm (6 ins) and body length of up to 5 cm (2 ins).

They are covered with hair and usually dark brown in colour, with some displaying bright red hairs on their venom glands.

When Brazilian wandering spiders feel threatened, they adopt a distinctive “attacking” stance with their front legs in the air, swaying from side to side.

How do they attack?

The spiders use bites as their main form of attack but do not always deliver venom, using it only in an estimated third of bites.

They eat insects and small mammals, including other spiders, amphibians, reptiles and mice, hunting them on the ground and killing with an ambush or direct attack.

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How to Identify a Brazilian Wandering Spider

Last Updated: February 12, 2021 Approved

This article was co-authored by wikiHow Staff . Our trained team of editors and researchers validate articles for accuracy and comprehensiveness. wikiHow's Content Management Team carefully monitors the work from our editorial staff to ensure that each article is backed by trusted research and meets our high quality standards. There are 8 references cited in this article, which can be found at the bottom of the page. wikiHow marks an article as reader-approved once it receives enough positive feedback. In this case, 93% of readers who voted found the article helpful, earning it our reader-approved status. This article has been viewed 133,780 times.

The Brazilian wandering spider is a large, hairy spider that lives in South and Central America. It’s considered the most venomous spider in the world. Since these spiders sometimes wander right into towns, cities, and shipments of fruit, it’s important to be able to recognize this spider and know its habitat. If you happen to be bitten, you should get immediate medical attention. Don’t panic, however! These bites can almost always be treated.

Recognizing a Brazilian Wandering Spider

• Some spiders may be more yellowish than brown. Others may appear to have black legs, or black bands on brown legs. [3] X Research source

• Do not try to trap this spider. Call animal control professionals if you think you have one in your home or outdoor buildings, and leave those buildings while you wait for help.

Being Aware of Their Habitats

• Small, unlit closets or nooks in homes
• Outdoor sheds and garages
• Unused clothes, shoes, or gloves
• Boxes of food in pantries
• Boxes in attics or garages

Avoiding a Bite

• If a spider falls out, don’t panic. Back away slowly and leave the area.

• You can also spray bug and spider repellant around doors and windows to ward off creepy crawlies.

Treating a Bite

• In men, these bites can also cause a long and painful erection.

Community Q&A

• Keep in mind that these spiders prefer to wander along the ground. Always wear sturdy shoes if you are in an area where these spiders are known to live. Thanks Helpful 2 Not Helpful 0
• These spiders are highly dangerous and should not be approached or provoked unless you are an expert such as an entomologist. They are recognized as one of the most dangerous spiders in the world and are the most venomous so they should always be treated with care and respect. Thanks Helpful 2 Not Helpful 0
• Children are more susceptible than adults to the venom of a Brazilian wandering spider, and you should ensure that any child who’s bitten gets medical attention as quickly as possible. Thanks Helpful 6 Not Helpful 0

You Might Also Like

• ↑ https://www.livescience.com/41591-brazilian-wandering-spiders.html
• ↑ http://www.wandering-spiders.net/phoneutria/gallery/
• ↑ https://animalcorner.co.uk/animals/brazilian-wandering-spider/
• ↑ http://bioweb.uwlax.edu/bio203/s2013/johnson_jor4/habitat.htm
• ↑ http://www.mayoclinic.org/diseases-conditions/spider-bites/manage/ptc-20204189
• ↑ https://www.livescience.com/37974-he-surprising-cause-of-most-spider-bites.html
• ↑ http://www.mayoclinic.org/first-aid/first-aid-spider-bites/basics/art-20056618
• ↑ http://www.webmd.com/first-aid/snakebite-treatment

About this article

To identify a Brazilian wandering spider, look for a spider with a long leg span of about 6 inches and a brown, hairy body. Also, carefully examine the spider from afar to see if it has large red fangs, which are common in Brazilian wandering spiders. Keep in mind that Brazilian wandering spiders only live in South and Central America. If you encounter one, move away slowly since Brazilian wandering spiders are aggressive and very poisonous. To learn how to avoid getting bitten by a Brazilian wandering spider, scroll down! Did this summary help you? Yes No

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Myth: deadly australian/brazilian spiders, myth: but there are really deadly spiders in australia and brazil..

Fact:  The  previous myth  page, where I said that no spider species anywhere can properly be called "deadly," generated more comments than any other on the site. Most were from Australians who were certain their country at least had truly deadly spiders, including the Sydney Funnelweb Spider,  Atrax robustus,  and the Redback Spider,  Latrodectus hasselti . Some also mentioned White-tailed Spiders, genus  Lampona . Some comments were from Brazilians who put forward their  Phoneutria  wandering spiders as the world's deadliest.

To start with, these people had misunderstood what I said. I  never  claimed that no human ever died from spider venom. What I said was, there is no species whose bite kills much more than 5% of its victims, nor any spider that kills within minutes, like in the movies. This applies just as strongly to Australia and Brazil as to the USA.

According to the Australian Museum, the number of human deaths from authentic spider bites of  any  kind in Australia since 1979 has been zero. A recent published medical study followed 750 genuine Australian spider bite cases with identified spiders over 27 months (1999-2001). Only 44 bites (6%, mostly redback spider bites) had significant effects. Only 6 redback bites and 1  Atrax  bite were serious enough to need antivenom. In no case was there any sign of allergic response to spider venom, and I have only seen one such case in North America in 44 years.

Atrax robustus , the Sydney Funnelweb Spider, is often publicized as the "world's deadliest."  Authentic medical information  suggests otherwise. There have been no deaths (out of 30-40 bites per year) since antivenom was introduced in 1980. During the 53 year period 1927-1979 there were 13 or 14 known deaths, which would be a death rate of  under one percent!  Although one child died in 15 minutes, adult fatalities typically took 2-3 days. 90% of Atrax bites are judged not serious enough to need antivenom.

Most serious spider bites in Australia are from the Redback,  Latrodectus hasselti , a close relative of American black widows with very similar venom and effects. The recent study mentioned above tallied 56 genuine redback bites. Only 37 (66%) had any serious effects, and only 6 (11%) were serious enough to need antivenom. There have been no redback-caused human deaths in several decades.

White-tailed spiders,  Lampona cylindrata  and relatives, have recently been blamed for Australian cases of severe necrotic lesions, but this connection was not based on enough evidence. The same authors who did the 750-bite study mentioned above, gathered a further 130 cases (aged 3-76 years) bitten by identified  Lampona  spiders. Local pain and itching were the only effects. No one developed any lesion or ulcer. White-tailed spiders are  not guilty  of doing any serious harm to humans;  this page  has more details.

Brazilian Wandering Spiders ( aranhas armadeiras ),  Phoneutria nigriventer ,  P. keyserlingi  and  P. fera , are sometimes said to have the world's most toxic spider venom – probably based on a well publicized study where mice were killed by intravenous injection of as little as 0.006 mg of venom. Since I'm a man, not a mouse, that doesn't worry me much. Authoritative sources state that over 7,000 authentic cases of human bites from these spiders have been recorded, with only around 10 known deaths, and about 2% of cases serious enough to need antivenom. So despite the surprisingly large number of bites, this spider is not exactly public enemy number one either.

Most medical conditions blamed on spiders by physicians lack confirmation that any actual spider was involved in the case. Spider bites of all kinds are rare events (as opposed to other bites and medical conditions that get wrongly blamed on spiders). Although it is possible for a spider bite to cause death, that is a very unlikely outcome and does not happen in enough cases to justify calling any spider "deadly."

Spider Myths

"Everything that 'everybody knows' about spiders is wrong!" — Rod Crawford sets the record straight with  Spider Myths .

Female Sydney Funnelweb Spider,  Atrax robustus . Human deaths from bite are rare. Photo:  Fir0002  from Wikimedia Commons, under  GNU Free Documentation License

Female White-Tailed Spider,  Lampona sp . Now proven 100% harmless! Photo: David McClenaghan, CSIRO from Wikimedia Commons

Female Brazilian Wandering Spider,  Phoneutria nigriventer . Human deaths from bite are rare. Photo: Paraná State Govt., Brazil

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AZ Animals (US)

The 15 Biggest Spiders Still Crawling the Earth Today

Posted: June 22, 2024 | Last updated: June 22, 2024

Spiders are a difficult topic for the arachnophobic. It can be difficult for some to wrap their minds around the fact that we live on the same planet as these massive eight-legged beasts, and this article probably won't help. However, spiders do more good for the environment in their short lives than one could ever guess. Without spiders, humans would not be able to survive on Earth. They would much rather run and hide than ever bite a human. In fact, they are terrified of us. What would you do if faced with killer giants, knowing that your only line of defense is to run, hide, and, as your last shot, bite? It's comical to think about our fear of spiders, even the "big" ones, when we are large bringers of destruction to all in our wake. Perhaps we should all try to be gentler with the creatures that make this planet possible.

Please click through the gallery above to view the next 20 photos of the largest spiders in our world.

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15. Israeli Desert Huntsman (Cerbalus aravaensis)

The gorgeous Israeli desert huntsman is native to Israel and has a leg span of 5.5 inches.

14. Brazilian Wandering Spider (Phoneutria fera)

The potentially deadly Brazil wandering spider is found throughout South America and has a leg span of 5.9 inches.

13. Golden Silk Orb Weaver (Trichonephila clavipes)

The golden silk orbweaver is a delicate spider found in North and South America. The females have a 6-inch legspan.

12. Giant Camel Spider (Galeodes arabs)

The giant camel spider calls the Middle Eastern deserts home and is 6 inches long.

11. Colombian Giant Tarantula (Megaphobema robustum)

The Colombian giant tarantula is 6 - 8 inches long and is found in the dense rainforest in Colombia.

10. Chaco Golden Knee Tarantula (Grammostola pulchripes)

The Chaco golden knee tarantula is a pretty black and gold spider. The spider calls Paraguay and Argentina home and has a large leg span of 7 inches.

9. Hercules Baboon Spider (Hysterocrates hercules)

The brown Hercules baboon spider is native to Africa, specifically Nigeria. The largest male on record recently made the news. The mysterious spiders have a leg span of 8 inches.

8. Sri Lankan Tarantula (Poecilotheria rajaei)

The beautiful Sri Lanka tarantula is sometimes called the "Sri Lanka ornamental tiger spider" and the "face-sized spider." They are endemic to Sri Lanka and grow to have a leg span of 8 inches.

7. Brazil Whiteknee Tarantula (Acanthoscurria geniculata)

The fuzzy Brazillian white tarantula lives throughout Brazil's rainforests. They grow to have an incredible leg span of 8.5 inches.

6. Queensland Whistling Tarantula (Selenocosmia crassipes)

The Queensland whistling tarantula is native throughout Australia. It has an enormous 8.7-inch leg span. They are sometimes called a "barking spider" or "bird-eating tarantula." The spider creates sound by rubbing rows of modified spines on the basal segments of their pedipalps against opposing spines on their jaw bases. They make this noise when trying to dissuade a predator.

5. Slate-Red Ornamental Tree Spider (Poecilotheria rufilata)

The slate-red ornamental tree spider is an Old World tarantula. Old World tarantulas do not have urticating hairs to kick at assailants. Instead, their only means of defense is to bite. They will only attack if running or hiding doesn't work first. They are native to India and have a leg span of nine inches.

4. Brazilian Giant Tawny Red Tarantula (Grammostola anthracina)

The Brazilian giant tawny red tarantula is the fourth largest spider in the world. They are native to Brazil and have a jaw-dropping leg span of 10 inches.

3. Brazilian Salmon Pink Birdeater (Lasiodora parahybana)

The Brazillian salmon pink birdeater is our third largest spider. They are native to Brazil and have a leg span of 10 inches.

2. Goliath Birdeater (Theraphosa blondi/stirmi)

The huge and weighty Goliath birdeater is the heaviest spider in the world. They are native to South America. The extra-large spider weighs a whopping 6 ounces and has a leg span of 11 inches.

1. Giant Huntsman Spider (Heteropoda maxima)

The giant huntsman spider is the largest measuring spider in the world. Its leg span is a mighty 12 inches! They are native to Laos and are harmless to humans. These mighty spiders are often welcomed into homes due to their excellent insect-removing abilities.

Interesting Facts About Giant Huntsman Spiders

One of the most fascinating aspects of Giant Huntsman spiders is their unique method of locomotion. They move sideways, similar to crabs, which is an uncommon trait among spiders. This side-walking ability allows them to quickly and efficiently navigate their cave environments, making them effective predators. Their speed and agility help them catch a variety of prey, including insects and even small vertebrates.

In terms of behavior, Giant Huntsman spiders are known for their reclusive nature. They typically inhabit secluded, dark places like caves and crevices, where they can avoid predators and human encounters. Despite their intimidating size and appearance, these spiders are not aggressive towards humans and will usually flee when threatened. Their secretive lifestyle and remarkable adaptations make them a subject of great interest to arachnologists and nature enthusiasts alike.

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• The Top 7 Biggest Spiders Crawling Around England
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Tiger mosquitos, Asian hornets and bed bugs: What climate change means for Europe’s ‘pest demographics’ haunting the Paris Olympics

About an hour outside Vienna, the Penny Markt in Krems an der Donau prides itself on two things: low, low prices, and the provenance of its meat and fresh produce. But one mild August day last year, shoppers rummaging for a locally-sourced bargain found a rather more exotic, if less welcome, surprise, lurking amid the banana crates.

The culprit was a stowaway Brazilian Wandering Spider, an 11cm black and red arachnid with a bite that causes convulsions, hypothermia, death and—if you’re of the male persuasion—a particularly painful case of uncontrolled erections. You can imagine the shock.

The store shut for precautionary disinfection, and the spider got away, never to be heard from again. But it’s hardly the only invasive creepy crawly to make its way into European tabloids lately.

France has acquired an unfortunate pre-Olympic reputation for rampant bed bug infestations, with Paris deputy mayor Emmanuel Grégoire warning people “no one is safe. You can catch them anywhere,” and reports of the bloodsuckers on the Eurostar causing panic in London.

Tiger mosquitoes, which can carry Dengue and Zika, have also been seen around the country, leading Paris authorities to bring in entomologist ‘detectives’ to track down their breeding spots.

The Turkish pharmaceutical industry, meanwhile, is eyeing Europe more broadly as an exciting new export market for scorpion antivenom .

Is climate change to blame for this apparent arthropodal invasion?

The reality is rather less apocalyptic than the headlines suggest, says Dr Matt Green, principal entomologist at UK-based global pest control company Rentokil Initial, which has operations across the continent.

We’re nowhere close to Dengue becoming endemic. Reports of French bed bugs rose largely because people saw horror headlines and started looking under their mattresses. And if we are generally seeing more invasive species it’s mostly not due to rising temperatures.

“I’m often asked how climate change is affecting our business. Well, given that humans have already transported all the major pests to pretty much every country, and certainly every major human center of activity, not as much as you might think,” Green tells Fortune .

The good news is that those worrying about bumping into errant Brazilian Wandering Spiders can relax.

Most species need more than a mere rise in temperatures to make a home in new and very different ecosystems. For example, the Sheerness docks near London have had a population of 10,000 yellow scorpions for centuries , since merchant ships brought them from continental Europe, but these harmless critters haven’t spread because conditions aren’t right.  

What climate change is doing to Europe’s pest population

This is not to say climate change isn’t affecting Europe’s pest profile.

Termites—long a problem in Mediterranean countries—are munching their way into Northern Europe with rising temperatures, though the relative lack of timber buildings means they’re unlikely to cause widespread economic harm there.

Aedes mosquitoes—the genus which includes tiger mosquitoes—are well established in Italy, and getting there in France, which means countries like Switzerland are unlikely to be spared.

“Europe is already seeing how climate change is creating more favorable conditions for invasive mosquitoes to spread into previously unaffected areas,” European Centre for Disease Prevention and Control director Andrea Ammon told the BBC.

Fortunately, these are not the kind that carry malaria—that’s the Anopheles , which is unlikely to spread into Europe due to the absence of large bodies of standing water that—unlike Aedes —it needs to breed.

The same can’t be said for Asian hornets which, depending on where you live, could soon be coming to a picnic near you. “They’re moving through France pretty easily, and there have been instances of them overwintering in the U.K., which means we’ve probably got these now, so make your peace with it,” Green says.

Then there are bed bugs. Even before the recent surge, infestations were costing the French economy €230 million ($246 million) annually, according to health agency Anses . Callouts can set back hotels thousands of dollars in treatments and lost income, and could create hysteria and panic through the Paris Olympics.

These six-legged vampires may have been there all along, but they do prefer warmer weather.

“When the temperature inside your house is 25 to 26 degrees Celsius (77 to 78.8 Fahrenheit), it takes only five days for the bed bug eggs to hatch. In normal conditions, when the temperature is around 20 degrees Celsius, it takes 10 days,” entomologist and National Institute for the Study and Fight Against Bedbugs cofounder Jean-Michel Bérenger told Wired during the height of the panic last year

How Europe’s pests are changing beyond climate change

Whether helped by rising temperatures or not, the pests we’re likely to see more of are the ones that are best adapted to humans and our behavior—and it is our behavior that is helping them to spread.

In rural settings this is most often through monocultural agriculture, though sometimes all it takes is a penchant for importing non-native plants.

The oak processionary moth—a species endemic to Southern Europe, which damages forests and releases hairs that can irritate skin, eyes and airways— established a foothold in the U.K. in the 2000s, when an oak was shipped from Europe. Ironically, it happened very close to the Royal Botanical Gardens at Kew, where authorities monitor such things.

It’s the urban pests you’re more likely to notice, however.

Rats, mice, cockroaches and the like all share characteristics that make them ideally suited to living intimately with humans, whether we want them to or not. They’re small, capable of crawling through tight spaces, generally dark and nocturnal, making them hard to spot. Crucially, they’re also omnivorous.

“They’re massively flexible, so they won’t care about one or two degrees [change in temperature]. They’re already living in air conditioned buildings,” says Rentokil’s Green. “Some moths in warehouses barely fly these days. They don’t have to. They’ve just been living in a world full of food, getting moved around by humans. It’s a hell of a life.”

Sometimes it’s a well-intentioned or necessary change in human behavior that helps urban pests to proliferate.

Media frenzy aside, bed bug populations did rapidly increase around the world in the early 21st century. In Australia , the rise was between 500% and 4,500%; in New York City, bed bug complaints to the council jumped from 537 in 2004 to 10,985 in 2009, although they have since dropped .

Entomologists attribute the resurgence to the end of the DDT era—the infamous insecticide dramatically cut global insect pest numbers in the mid to late 20th century, before serious environmental and health concerns ended its use, and species started to develop resistance. In essence, we’re returning to historical norms from a period of unusually low insect activity.

Don’t expect this to change. Although the pest control industry is deploying increasingly sophisticated monitoring strategies and ‘physical’ interventions, such as steam cleaning rooms with bed bugs, moving away from chemical controls means we lose what had been a powerful weapon against infestation.

Something similar may be about to happen with rats, at least in Europe, where regulators are taking an increasingly dim view on the use of anticoagulant rodenticides.

This may be for good reasons, but it has pest controllers nervous. As one put it off the record, “there’s a whole generation of pest controllers that have been trained to put rat poison into bait boxes. If you take that away from the market, what do you have left? To quote Aliens , what are we supposed to use, harsh language?”

Humanity has made many species extinct, mostly unintentionally, and it is continuing to do so. The species that at least some of us would like less of, however, have proven stubbornly resilient. Almost by definition, pests thrive when we do.

So what can we expect? In Europe, climate change and human activity are unlikely to make lethal spiders a regular part of grocery shopping, or to bring about tropical levels of mosquito-borne diseases.

But they will alter the populations of fauna we share our environment with. Get used to Aedes and Asian hornets; be vigilant for rats and bed bugs.

What perhaps will change the most, though, is our expectation of what pest control means. With the spray-it-first-ask-questions-later approach firmly consigned to the history books, eliminating pests at first appearance may end up being remembered as a very 20th century idea.

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