Are Banana Spiders Poisonous or Dangerous?

When searching for information about banana spiders, it might be confusing to browse the results. Some will say that banana spiders are completely harmless, some will argue that their bite barely compares to a bee sting, while others will tell you that banana spiders are highly venomous. The right answer is either of the three. To determine if a banana spider is venomous, you should first figure out its type.

Around five types of banana spiders can be found across Africa, Asia, North America, and Oceania. Yet, these banana spiders have varying venom levels depending on the species. So, are banana spiders poisonous or dangerous?

Some banana spiders are harmless to humans and do not bite unless provoked, while there are specific types of banana spiders that are naturally aggressive and are highly poisonous.

Do Banana Spiders Bite?

All types of banana spiders bite, especially when provoked. However, the severity of their bites depends on the kind of banana spider encountered. Some banana spider bites barely leave symptoms and only feel like a mild bee sting. However, more aggressive types of banana spiders can cause much severe consequences, even death.

There are about five kinds of spiders that are commonly called banana spiders, making it challenging to identify which is harmful and which isn’t. To clear your mind about the varying levels of banana spiders’ venom, here is a quick guide about some types of banana spiders, ranked by their venom and risk levels:

Golden silk orb-weaver spiders (Nephila)

Also known as the giant wood spider, writing spider, or calico spider, these cylindrical spiders are non-aggressive and will only bite when provoked. Their bites are mild and may only feel like a slight sting but will cause redness and no other symptoms. They are venomous, but their venom should not be of any effect on humans.

Hawaiian garden spider (Argiope happens)

As confusing as it is, these spiders are also called orb-weaving spiders or banana spiders. Hawaiian garden spiders are not harmful to humans and are even helpful to the environment. They prey on bugs and other small insects, which helps eliminate unwanted pests on plants and flowers. They can bite, but only on rare occasions. These banana spiders live peacefully in gardens and cannot do anything that can cause humans harm.

Banana spider (Cupiennius)

Banana spiders of the Cupiennius genus are often mistaken for poisonous banana spiders. However, these brown, furry arachnids with skinny legs in South and Central America are far from dangerous. Banana spiders are slightly venomous, but their bites are no more painful than a bee sting. The effect of their venom is also comparable to the impact of a bee sting. 

Golden silk-orb weaver (Trichonephila clavipes)

Do not get confused with the first golden silk orb-weaver spiders (Nephila) mentioned. These arachnids have darker and longer bodies. Yet, like the former, golden silk-orb weavers only bite when disturbed or handled roughly. They can inject venom into humans, but its effect won’t be enough to cause any harm. Their bites can only leave mild redness on the site of the bite.

Brazilian wandering spider (Phoneutria)

When people say that a poisonous banana spider bite is dangerous, or venomous, they are probably talking about the highly venomous Brazilian wandering spider. They are often discovered in banana shipments hailing from Central and South America. Their bright red mouthparts are a warning because the Brazilian wandering spider bites are dangerously poisonous to humans and can kill young children.

Are Banana Spiders Dangerous to Humans?

As mentioned, there are different types of banana spiders. Most of them are not harmful at all, and if they bite, they can only leave mild symptoms and a not-so-deep bite wound that is no riskier than a bee sting. Yet, a specific type of banana spider can kill children, as their venom is highly poisonous for humans.

The four other types of banana spiders are all harmless to humans. Yet, they can still bite when provoked. These types of banana spiders are known to be very shy and are more likely to run and hide than bite. The most dangerous of the five banana spiders, the Brazilian wandering spider, is also shy.

The Brazilian wandering spiders have the reputation of being aggressive because of their dangerous bites. However, Brazilian banana spiders only bite as a defense mechanism. When these harmful spiders feel threatened, they give a warning sign before biting by raising their front pair of legs.

How Dangerous are Banana Spiders?

All banana spiders bite, yet some bites are more painful than the others. The less venomous banana spider bites will only be as painful or less as being stung by a bee and won’t cause other symptoms. Occasionally, the bites can also cause redness and blistering. However, people allergic to a banana spider’s venom can develop some allergic reactions, including breathing problems, hives, and swelling. 

The Brazilian wandering banana spider, on the other hand, causes more severe symptoms to humans. The Brazilian banana spider’s venom is toxic to the human nervous system, and its bite can cause excessive drooling and irregular heartbeat.

However, anti-venom for these spider bites is available, and fatalities are rare when attended to immediately.

Symptoms of Brazilian banana spider bites often appear about 2 to 3 hours after the bite and include:

• Heavy sweating
• Swelling of bite site and rash
• Burning sensation 
• Pain that spread to other areas
• Difficulty breathing
• Paleness
• Blurred vision
• Involuntary muscle contractions
• Vomiting
• Increased blood pressure
• Palpitations
• Severe chest and belly pain
• Bluish bite wound
• Missed heartbeat

Depending on the severity of the symptoms, the bite can cause death if not treated immediately.

How to Avoid Banana Spiders

The most poisonous banana spider bite, the Brazilian wandering spider, is often found in banana shipments. If you notice that your house is infested with these spiders, you must declutter areas in your home to keep them from hiding. Insecticides can repel them, but you may need professional help for better and safer results.

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