A Guide to The World's Biggest Bugs

Discover some of the world's most giant bugs, along with a host of interesting facts that you won't believe.

Mar 17, 2023By Donna Hobson

If you could time travel hundreds of millions of years in the past, you would come face-to-face with some of the gigantic insect species that once called Earth home. The largest of these was a "griffin fly," a kind of prehistoric dragonfly whose wingspan could extend to 75cm.

Today, nothing quite so fearsome roams the Earth, but some magnificent bugs are still around. Many of these are endangered or live in remote areas of the world, so you're unlikely to stumble across one in your back garden. Still, these insects are fascinating; here's why.

Goliath Beetle

goliath beetle
Image Source: http://sk.pinterest.com/pin/356347389242987568/

Goliath Beetles are strong contenders as the world's biggest insects, thanks to their impressive length and weight. As adults, these beetles range in size from 2.1 to 4.3 inches long and can weigh as much as 1.8 ounces. Still, their heaviest weight occurs during the larval stage when they weigh as much as 3.5 ounces.

These beetles possess six legs with sharp claws and two pairs of wings (called elytra). Not only are they one of the biggest bugs in the world, but they are also one of the strongest and can lift up to 850 times their own body weight. To put that into perspective: if humans could lift 850 times their own body weight, we would be able to carry objects around seven tons!

Giant Weta

giant weta new zealand
Image Source: 10 Intense Facts About the Giant Weta | Mental Floss

A weta is a type of insect native to New Zealand; it is more closely related to crickets than any other insect in the country. The weta is an essential part of the ecosystem in New Zealand because they are a primary food source for many birds and reptiles. They also pollinate plants and provide nutrients for other animals by eating rotting leaves, which would otherwise accumulate on the forest floor.

Deriving its name from the Maori word for "the god of bad looks," the weta sparks fear in most people who encounter it, even though it is harmless to humans. These insects can grow to lengths of four inches and weigh up to three ounces, which is why some consider them the biggest insects in the world.

Queen Alexandra Birdwing

alexandra birdwing butterfly
Image Source: Star objects of our collection – The Queen Alexandra’s birdwing | Entomology Manchester (wordpress.com)

The Queen Alexandra Birdwing is a rare butterfly indigenous to Papua New Guinea. The IUCN classifies this butterfly as an endangered species, and it's believed that less than 100 of these butterflies are left in the world. The Queen Alexandra Birdwings are so rare because they only live in a tiny region (which may be as small as 1,200 sq. km) on the island of Papua New Guinea, where they feed off fig trees and other plants.

They are a type of swallowtail butterfly, one of the world's largest butterflies; they have a wingspan extending up to 28cm, and their colors can range from green to yellow and orange with black stripes. The female is the bigger birdwing, but the male possesses brighter coloring.

Stick Insects

giant stick insect
Image Source: This insect is TWO FEET long | Sierra Club

When it comes to the longest insect in the world, there's no competition for the two-foot-long stick insect recently discovered in China - yes, there really is a stick insect that's longer than a human being (the world's shortest human being, at least).

As the name suggests, these insects resemble their surrounding plant matter, which helps them to blend in with their environment and escape predators. And that's not their only impressive defense; some can release a foul odor while others can temporarily blind predators by secreting a specialized liquid. Many can regenerate appendages too, which is pretty handy if an attacker happens to bite off a leg.

In addition, several species of stick insects can reproduce parthenogenetically, which means the females can lay unfertilized eggs that will hatch and grow into new females. These eggs look like seeds that help deter predators from taking a closer look.

Tarantula Hawk

tarantula hawk fly
Image Source: Tarantula hawks are a terrifying insect — especially for tarantulas (gosanangelo.com)

The tarantula hawk is a wasp that hunts tarantulas. The female stings and paralyzes a spider using her venom, then drags it to an underground lair (or other dark places), where she lays an egg on its body; the larva consumes the paralyzed arachnid alive from the inside out.

And these horrific hunters are the largest wasps in the world, growing up to 2.7 inches in length with a 4.5-inch wingspan. The Tarantula Hawk is also known for its massive stinger, which can grow well over a quarter of an inch; the sting is one of the most painful insect stings worldwide, second only to the bullet.

Atlas Moth

atlas moth
Image Source: One Of World's Biggest Moths Seen In US For First Time, Stumping Scientists | IFLScience

The Atlas moth possesses an impressive wingspan - more expansive than a human hand - making it one of the largest species of moth in the world. These moths have wingspan of up to 12 inches, giving them a surface area as large as 62 square inches. They possess reddish-brown wings and live in tropical forest habitats throughout Asia. Sadly, this extraordinary creature cannot eat, so it has a very short lifespan.

That doesn't prevent the larvae from eating as much food as possible before they enter the pupal stage, first working through their eggshells and then gorging on leaves from guava, citrus, and cinnamon trees. As adults, their primary purpose is to mate, so they don't travel far, conserving their energy by remaining as still as they can.

Mydas Fly

Mydas fly
Image Source: Mydas sp. - Mydas fly - Wikipedia

The Mydas fly is the largest fly in the world that can trick predators by mimicking bees and stinging wasps. These flies can reach lengths of 2.4 inches; still, their large size doesn't prevent them from being agile, and they love to snack on other flies, as well as the sweet taste of nectar.

Most of this species is native to arid regions, but if you saw a Mydas fly, it might frighten you. Still, these incredible flies can act as a natural pest control, often laying their eggs next to decaying matter. Their babies feed on other grubs, preventing the latter from chewing through cultivated plants.

Donna Hobson
By Donna Hobson

Donna believes that keeping a pet is the key to a happy life. Over the years, many creatures have passed through her home - Sooty the cat, Millie the rabbit, Stuart (Little) the guinea pig, and Trixie the tortoise, alongside her pet goldfish, Zippy, who lived to the grand old age of 24 years! She currently resides with her black kitten Jinx and an aquarium full of fish and snails to entrance them both. When she is not looking after her pets, Donna enjoys researching and writing the answers to all your pet-related wonders.