Most Venomous Insects in the World: 9 Creepy Crawlies to Avoid

most venomous insects in the world

They might be among the world’s smallest living creatures, populating every field, jungle, and backyard in the world. But insects can pose a considerable threat to humans and animals, especially when their stings pack a potent punch.

There are hundreds of venomous insect species, but that doesn’t mean they’re all dangerous. Insects are crucial to our ecosystems, and some carry venom that they will never even use. Still, there are many critters that you should avoid, and their poisonous glands can prove lethal to humans.

This guide looks at nine of the most venomous insects in the world to find out if venom always means danger and some of the tell-tale signs that an insect is poisonous. Keep reading, and you might just find you’ve already had a few run-ins with the most venomous insect in the world…  

Blister Beetle

Black and red beetle
Photo by Envato Elements

The characteristic warning stripes of this gruesome creepy-crawly should be your first sign to give it a wide berth. Appropriately called the blister beetle, getting in contact with the chemical cantharidin that the beetle secretes can result in painful boils and blisters appearing on the surface of your skin. Cantharidin can be used to remove warts, but ingesting the toxin can destroy the lining of your gastrointestinal tract and lead to death. 

We probably don’t have to tell you not to go around eating beetles, but still, it’s important to know that you shouldn’t even handle these bugs for the risk of skin irritation. They also pose a massive threat to farm animals. Attracted to alfalfa, they can accidentally get ground up in the hay, and just a few beetles can release enough cantharidin to kill a horse. If a bird were to prey on the blister beetle, the poisonous secretion would likely cause convulsions and death. 

Oriental Wasp/Murder Hornet

Murder hornet
Photo by Studio_OMG on Envato Elements

Measuring two to three inches long, if the Japanese Murder Hornet or Oriental Wasp wasn’t enough of a frightening sight, its name is sure to scare you off. Hornets and wasps belong to the Hymenoptera order, one of the world’s most venomous and dangerous insect groups. It’s only the females that sting, but you’ll be lucky if you only come away with severe pain when encountering a murder hornet. 

These giant wasps pose the biggest threat to people allergic to hymenopteran stings, which make up about five to seven percent of the world’s population. In extreme cases, a sting from a murder hornet can result in anaphylactic shock, severe inflammation, cardiac arrest, and subsequent death. 

But even if you don’t have allergies, you should still keep your distance from the formidable murder hornet. Hornets are one of the most aggressive insects on the planet, and if they come at you as a group, you won’t stand a chance. Victims can receive close to hundreds of stings in a matter of minutes, and the payload of venom would exceed that of any other poisonous creature. 

The wasps typically live in remote locations such as the islands off Japan, hence their name. But they also dwell in popular tourist areas like Bali in Indonesia. The best thing you can do is avoid provoking any hymenopteran you encounter and don’t run around flailing your arms, as hard as it is to resist.

The Monarch Butterfly

The Monarch Butterfly
Photo by twenty20photos on Envato Elements

Butterflies definitely won’t be the first creature to come to mind when you think of the most venomous insects in the world. These majestic winged insects are more often associated with beauty and elegance than danger, but the revered monarch butterfly is one of the most poisonous creatures out there. 

It might not bite or sting, but it is deadly to any human who tries to eat it. Most insect larvae are edible and nutritious, but the monarch caterpillar feeds almost exclusively on milkweed, a highly toxic substance that it stores for life. Ingestion of the monarch caterpillar, butterfly, or larvae will give a human a significant dose of milkweed poison that can cause cardiac arrest. 

Their toxic milk sap diet makes monarchs inedible to predators. All the more reason to not go around eating insects. But this does leave dogs and cats at risk of being poisoned. 

Harvester Ants

red ant on leaf
Photo by twenty20photos on Envato Elements

Ants are among the most venomous insects globally, and the 22 species of harvester ant that populate crops all over the world pack the most punch when it comes to deadly poison. 

Ants generally aren’t to be feared because one small critter is unlikely to take down a whole human unless they have a severe allergic reaction to its bite. But harvester ants are highly aggressive and have been known to actively chase humans, destroying anything in their path and posing a considerable threat to agriculture. 

If an animal or person interacted with a harvester ant mound, nothing would stop the tiny insects from swarming and attacking. Harvester ants are actually the most venomous insect in the world by volume, even if they’re not the most dangerous. Just a few stings are enough to kill a rodent, and a swarm of harvester ants could cause painful boils, severe swelling, and possibly deadly infections for a human.

Yellowjacket

Wasp
Photo by EdVal on Envato Elements

Officially known as Vespula, yellowjackets are thin wasps with black and yellow coloring and are often confused with bees despite being considerably less rotund. This makes their appearance seemingly less daunting than their deadly counterparts, the murder hornet. But yellowjackets are not to be underestimated.

Yellowjackets inhabit isolated areas and live in nests. Unlike bees, which can only sting once before losing their piercer, yellowjackets can sting countless times. Piercing skin with their stinger, they inject venom into their victims, causing sudden, burning pain, often compared to a hot needle penetrating the site. Fatigue and itching are all common symptoms, but severe inflammation or anaphylaxis can lead to death for some people.   

Cow Killer

Green ant
Photo by Pelooyan on Envato Elements

Although a type of ant, this unapproachable creepy-crawly resembles a species of its own. Officially called velvet ants, their nickname of the “cow-killer” didn’t come from their friendly nature. 

Male velvet ants have wings instead of a stinger, making them essentially harmless. But female velvet ants can deliver a powerful sting, and although one won’t kill a cow if the cow steps on the insect, it releases an alarm pheromone that mobilizes a colony for an attack. Multiple stings from velvet ants could kill a cow and cause severe pain to a human and even death. Worse yet, they’re known to sting and bite simultaneously. Since there is venom in their saliva, too, you’ll get a double dose with each attack. 

Luckily, these ants aren’t aggressive and will avoid danger, but their bright red bodies serve as an appropriate warning to keep a wide berth. They live in fields and meadows all over the United States. Cow killer ants are just another reason to never run around barefoot in nature.

Assassin Caterpillar

Hairy caterpillar
Photo by Garakta Studio on Envato Elements

Lonomia Obliqua, commonly known as the “assassin caterpillar,” is as unapproachable as its name implies. Eventually metamorphizing into a harmless, brown silkworm moth, in its larvae from the caterpillar, is one of the deadliest insects found in the Americas.

The caterpillars grow to a relatively meager two inches in length and can be brown, gray, or green and covered in spines. These spines detach very quickly and release a potent venom when they penetrate human skin. This poison carried by the caterpillar is so lethal that it can interrupt the blood’s ability to clot and wreak havoc on a human’s internal organs, even causing hemorrhages in the brain. 

One spine from the assassin caterpillar is tiny and unlikely to cause much damage if floating around or on the ground. But if you come in contact with a few, or worse, a colony of these fury caterpillars, who are known to congregate in groups, it could be a different story.   

They’re native to South America, so you don’t need to worry too much about an infestation in your own backyard. But next time you’re trekking the Andes or vacationing in sunny Mexico, keep your distance from oaks, willows, and lemon trees where they commonly dwell and camouflage well into the leaves and bark. 

Black Widow Spider

Black widow spider
Photo by Veronica Lorine on Unsplash

Although not technically an insect, this formidable arachnid deserves a spot on our list for making our skin crawl more than any of the creepy crawlies here. Spiders are a distant ancestor of the Insecta class of creatures, but they’re often grouped when discussing dangerous critters because of their deadly venom. 

Some people are only slightly affected by a black widow bite, but they’re the lucky ones. The venom can affect the human nervous system, and a severe response can result in immediate burning, swelling, and excruciating pain. Again, it’s the females that pack the most punch when it comes to poison. Their large venom glands and long fangs are for predation and defense, but if threatened, a human can become come victim to them.

Their striking appearance makes them easily recognizable with a bulbous body, eight long legs, and a bright red underbelly. They’re also not as exotic and rare as you might think, populating the globe from North and South America to Australia, Africa, Asia, and even Southern Europe.  

Indian Red Scorpion and The Deathstalker

Yellow scorpion
Photo by Creativenature_NL on Envato Elements

Scorpions are also predatory arachnids but belong to their own order of creepy-crawlies called Scorpiones. Like insects, they usually live outdoors in temperate and tropical climates but can survive harsh desert conditions, too. They can also be unwanted visitors in residential homes. 

Scorpions are easily identified by their long bodies, distinct pincers, and upturned stingers, where their deadly venom is stored. Scorpion venom is a neurotoxin, meaning it acts on the human nervous system and can send people into cardiac arrest. Scorpions usually only sting when provoked, and most stings won’t prove lethal. Still, the Indian Red Scorpion and the appropriately named Deathstalker are not among these harmless varieties.

With the most potent stingers than any other scorpions in the world, victims of stings from both species typically experience extreme nausea, skin discoloration, heart problems, and even pulmonary edema, which is fluid in the lungs and can be fatal. The deathstalker is a translucent green scorpion with defining pincers, while the Indian Red is a light brown critter with fat pincers and a particularly curled stinger. Both can be found in Central Africa and all over South Asia and should be avoided at all costs.  

What is the most dangerous insect in the world? 

The most dangerous insect in the world isn’t venomous at all, and this is the case for many deadly creepy crawlies. Instead, the diseases that parasitical bugs can carry cause more deaths worldwide than any insect bite or sting. Mosquitos are the most deadly insects of all time. While they carry a variety of harmful pathogens, the biggest killer is malaria, with around 219 million cases of the disease put down the mosquito bites every year.

It’s thought more than 435,000 of these result in death annually, which is far more than any insect bite, sting, or disease can cause. Luckily, only the Anopheles mosquito can transmit malaria, but these are very common in marshes, mangroves, rice fields, and vegetation all over Africa and Central Asia.  

Which insects can bite?

Common biting and blood-sucking insects include ticks, which are technically arachnids, bedbugs, mosquitos, ants, and flies, like black flies, sand flies, and deer flies. But not all biting insects are nasty, or their venom is of such a low dose that it wouldn’t do much harm to a human. However, many can still carry diseases from one host to another, even if they aren’t poisonous. Insects are near-perfect vectors, making them huge killers in impoverished nations. 

Are spider bites poisonous?

Unbeknownst to many, almost all spiders are poisonous, but this doesn’t mean they pose a considerable threat to humans. The fangs of most spiders species are too short or poorly placed to make contact with human skin and even too fragile to penetrate it if they could.

Most venomous spider bites are also unlikely to cause much bother beyond soreness and itching, which should subside in a matter of hours. But some spiders in the far corners of the earth can deliver a lethal dose of poison. These include the Brown Recluse, the Brazilian Wandering Spider, the Yellow Sac Spider, and the Black Widow. Still, death rates are low as most of these species are extremely rare.  

Reece Toth

Reece is the creator and editor of Travel Snippet. He has visited more than 38 countries over a 10-year period. His travels have taken him through the majestic mountains of Italy, into the cities of central Europe, across the islands of Indonesia, and to the beaches of Thailand, where he is currently living. He is passionate about travel and shares his expertise by providing the best travel tips and tricks to help you plan your next adventure.

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