What are the 10 most venomous animals in the world? To answer the question, let’s first define “most venomous.” After all, some folks may calculate venomosity using a potency-versus-size calculation; others may focus on victim statistics across the animal kingdom. However, for our purposes, “most venomous” means “venomous animals most dangerous to humans.”
One more thing to define is the difference between “venomous” and “poisonous.” Venomous species actively inject toxic serums. Conversely, poisonous animals passively disperse toxins. For example, if eaten, puffer fish can prove deadly to humans because Homo sapiens are lethally allergic to the fish’s flesh. However, puffer fish don’t inject toxic liquids into humans as a defense mechanism, so they’re not venomous.
Now that we’ve surveyed the landscape, let’s explore the 10 most venomous animals in the world that Mother Nature has packed with dangerous loads for personal protection.
Most Venomous Spider in the World: Funnel-Web Spider
Two species in the family Atracidae — Sydney funnel-web spiders and tree-dwelling funnel-web spiders — rank among the most venomous arachnids in the world. Their bites can be fatal if left untreated, and they frequently collide with humans, making them our pick for the most venomous spider.
Both species are medium-sized and native to Australia. Female nibbles are harmless to humans, but male bites can incapacitate victims. Without treatment, they can even prove fatal.
When threatened, venomous funnel-webs stand up on their hind legs and flash their fangs. If the threat doesn’t subside, they will bite targets up to 28 times, and symptoms typically show within an hour. The initial injection can be excruciating and trigger involuntary twitching and disorientation.
Unfortunately, venomous funnel-web spiders frequently collide with people. Thankfully, scientists have developed a highly effective, life-saving antivenom that’s saved thousands of lives over several decades. Interestingly, funnel-web spiders affect humans and primates but not other mammals.
These crawling assassins with glossy exteriors come in blue-black, all-black, brown, and dark-purple. They’re usually 0.5 to 2 inches long, and females are larger than males. However, in 2016, scientists at the Australian Reptile Park welcomed a male funnel-web spider with a four-inch leg span, the largest specimen ever reported!
Most Venomous Jellyfish: Box Jellyfish
There are 51 species of box jellyfish, and four — Chironex fleckeri, Carukia barnesi, Malo kingi, and Chironex yamaguchii — are highly venomous! Since 1883, when box jellyfish deaths first started being recorded, the box-shaped, gelatinous carnivores have claimed hundreds of human lives. In the Philippines alone, approximately 20 people a year pass away from sting complications.
Box jellyfish bodies are about eight inches long, and their tentacles reach 10 feet! Most individuals have 15 tentacles per corner, and each tentacle sports about 500,000 venom injectors! In other words, a single box jellyfish has about 30,000,000 venomous stingers!
Thankfully, the overwhelming majority of jellyfish stings are mild. But every so often, individuals deploy full loads, and the unlucky victims can pass away within minutes.
Most Venomous Snake in the World: Saw-Scaled Viper
The most venomous snake in North America is the eastern diamondback rattlesnake, but the most venomous snake in the world is the saw-scaled viper — also known as a “carpet viper.” These slithering executioners belong to the genus Echis and can be found in Africa, India, the Middle East, Pakistan, and Sri Lanka.
But trust us, the last thing you want is to come across one — because their bites are agonizingly painful and more than occasionally fatal! Echises hold the world record for most snakebite deaths in humans. In their native regions, the genus is responsible for more fatalities than all other area snakes combined. In addition to death, saw-scaled vipers cause thousands of amputations.
Females of the species are twice as venomous than males, and their deadly serum is a cocktail of neurotoxins, cardiotoxins, hemotoxins, and cytotoxins, which attack the nervous system, heart, blood, and cells, respectively.
Saw-scaled spiders glide across their arid regions using sideways locomotion and are between one and three feet long. Individuals have brown, gray, or orange skin, dark dorsal patches, and pear-shaped heads.
Read more about snakes, which live all over the world, here.
Most Venomous Insect in the World: Harvester Ant
There are 26 species of harvester ants — many of which are harmless and frequently used in ant farms. But the Pogonomyrmex maricopa — aka the “maricopa harvester ant” — is widely considered the most venomous insect on Earth.
Maricopas stings are 20 times more toxic than honey bee venom and 35 times more toxic than western diamondback rattlesnakes! If a colony of Maricopa harvester ants targets a human, the insects can, technically, kill the person with several hundred bites. Typically, though, victims can escape before that happens.
Regardless, many people suffer through considerable pain that lingers for two to eight hours after an attack.
Maricopa harvester ants only live one to three months. They reside in Arizona, California, Colorado, New Mexico, Nevada, Texas, and Utah — in addition to the Mexican states of Baja California, Chihuahua, Sinaloa, and Sonora. While maricopa numbers are currently healthy, myrmecologists — people who study ants — warn that populations are declining. Red fire ants and Argentine ants, both invasive species, are encroaching on maricopa territory, and the competition for food is growing fierce.
Most Venomous Animal in the World to Humans: Inland Taipan Snake
One bite from an inland taipan snake has enough venom to kill 100 adult people! By volume, it’s the most venomous animal in the world to humans. Called dandaorabilla by Aboriginal Australians, these six- to eight-feet long serum slayers are fast, accurate, and release a little venom with every bite.
But there’s good news. Inland taipan snakes are timid and reclusive and do everything in their power to steer clear of us. They’re so avoidant of people that scientists could not find enough to conduct studies between 1882 — when first discovered — and 1972! Plus, inland taipans are nocturnal and rarely come out during the day.
Most Venomous Scorpion in the World: Indian Red Scorpion
With their small pinchers, bulbous tails, and large stingers, Indian red scorpions top the most venomous scorpion list. Fatality reports fluctuate between 8 and 40 percent, and sadly, children are most affected by Indian red scorpion venom.
Located in India, Pakistan, Nepal, and Sri Lanka, Indian red scorpions are about five to nine centimeters long, and most don’t live more than five years. They prefer tropical and sub-tropical habitats and are regularly captured for research projects and the illegal pet trade.
After an attack, humans may start vomiting, sweating uncontrollably, convulsing, or even fall into a state of unconsciousness.
But the Indian red scorpion’s venom isn’t all bad. Scientists believe the serum could lead to pharmaceutical advancements to better fight cancer, malaria, and various dermatological conditions.
Most Venomous Fish in the World: Stonefish
There are five species of Synanceias — commonly called stonefish — and you don’t want to encounter any of them at the beach! Their venom-filled dorsal fins sting faster than you can say “ouch!” And ouch you will be saying if you’re stung! Not only are stonefish stings extremely painful, but they can also kill if not treated.
Beaches in stonefish regions often have vinegar stations because the common household item significantly reduces Synanceia stings on contact. Area hospitals and medical clinics are typically stocked with antivenom as well. Since scientists developed an effective antivenom for stonefish stings, there haven’t been any reported deaths. In fact, the last Synanceia-related fatality occurred in 1915!
Most Venomous Mollusks: Cone Snail
Plentiful in Indo-Pacific waters, cone snails are the most unassuming venomous animals in the world. But don’t be fooled! These mollusks may be the aquatic world’s couch potatoes, but they’re lethal!
Cone snails come in 900 species, and their taxonomy has been in a state of flux for about a decade. But what scientists can agree on is that cone snails rank among the more venomous marine animals alive today.
Small cone snails aren’t dangerous to humans, but larger ones — which grow to nearly 10 inches — can be. Attacks can cause challenging symptoms because cone snail stingers are like hypodermic needles that deliver poisonous serum with precision.
Most Venomous Lizard: Mexican Beaded Lizard
Darting around the woodlands of Mexico and Guatemala are thousands of Mexican beaded lizards. They weigh about 2 pounds (800 grams) and have pink forked tongues, which they use to smell. They’re also the most venomous lizards to humans.
But lizards, in general, don’t pose much of a threat to people. And even though Mexican beaded lizards pack the most potent venom of any lizard species, only a handful of folks throughout history have succumbed to their bites.
Mexican beaded lizards carry poisonous serum in lower jaw glands. When the reptile strikes, it chews on victims to ensure a subcutaneous puncture. But the good news is that Mexican beaded lizards don’t attack humans often, and when they do, death is infrequent.
Despite their reluctance to strike and kill humans, people have vilified Mexican beaded lizards for centuries. According to lore, the leathery bounders have the power to make women miscarry with just a glance and cause lightning strikes with their tails! Moreover and wrongly, many folks think Mexican beaded lizards carry more venom than a rattlesnake. Unfortunately, all these myths and misconceptions are decimating their populations because people believe the tall tales and shoot them on site!
Another problem contributing to their downfall is their status as a hot commodity on the illegal pet market.
Most Venomous Mammal: Platypus
The platypus — commonly called the duck-billed platypus — is the most venomous mammal to humans. That said, they don’t present a significant threat to people. Like lizards, few mammals can cause severe damage, by venom injection, to homo sapiens.
Male platypuses deploy venom from “spurs” in their legs. The dose is enough to kill dogs and cats, but not us. That said, a platypus bite is nothing to sneeze at! They hurt and can cause temporary incapacitation, not to mention long-term pain sensitivity.
The semi-aquatic, egg-laying mammals live in eastern Australia, and today’s scientists value them as an evolutionary link to the far-distant past. But the research community wasn’t always keen on the duck-billed swimmers. When European naturalists first observed a platypus corpse, they dismissed it as “fake news,” insisting the hoax sample was Frankensteined from various creatures.
Read more about platypuses, which don’t have stomachs, here.
That’s our list of the 10 most venomous animals to humans. Stay safe out there!
Want to learn more fascinating facts about the Earth’s species? Check out our animal blog!