Largest Insects on Earth – Past and present

7th November 2020 | Life on Earth


The blog of March this year checked out insectoid aliens so this month I thought it would be fun to have a look at the insects of Earth. In particular a few of the largest ones, both current and past. There’s no doubt that insects are immensely varied, and  how they operate is [just as immensely] fascinating. So here goes with just five of the largest:

Current large insects

Most of us are used to insects that are relatively small. But there are some around that could easily cover most of your hand.

  • The Giant Weta is often cited as the heaviest insect on Earth. Large species can be up to 10 cm (4 in) excluding the legs and antennae. One captive female reached a mass of about 70 g (2.5 oz.), making it one of the heaviest documented insects in the world. But their body mass is usually no more than 35 grams.
  • Elephant beetle (Megasoma elephas) is a rhinoceros beetle belonging to the Scarabaeidae family. The males can grow up to 13 cm (5.1 in), but females are quite a lot smaller. They are actually black in color and covered with a coat of fine microscopic hairs. They are found in southern Mexico, Central America, and South American rain forests.
  • The Atlas beetle (Chalcosoma atlas) is a species of rhinoceros beetle (Scarabaeidae family). It is named after Atlas, a Titan condemned to hold up the sky for eternity in Greek mythology. The males are larger than the females, reaching a length of up to 13 centimeters (5.1 in). The larva of the Atlas beetle is known for its fierce behavior that includes biting if touched. Unverified reports exist of larvae that live together fighting to the death if there’s not enough space or food. Atlas beetles live in southern Asia, especially Indonesia.
  • The females of the Giant Longhorn beetle reach a length of 70-80 millimeters (2.8-3.1 in) and males 110-120 millimeters (4.3-4.7 in). Specimens up to 150 millimeters (5.9 in) have been captured. The giant longhorn beetle lives in Argentina, Colombia, French Guiana, Guyana, Venezuela, Trinidad & Tobago, Ecuador, Peru, Brazil, Bolivia, Paraguay, Panama, and Suriname.
  • One of the largest insects on Earth, the Goliath beetle, possesses a reinforced first pair of wings called elytra. They act as protective covers for their second pair of wings and abdomen. Only the second pair of wings (which are large and membranous) are actually used for flying. When not in use, they are kept completely folded beneath the elytra. The beetle’s legs end in a pair of sharp claws, useful for climbing on tree trunks and branches. Males have a Y-shaped horn on the head that is used as a crowbar in battles with other males over feeding sites or mates. Females are without a horn, having a wedge-shaped head which assists in burrowing when they lay eggs.


Large insects from the past

Insects of the past tended to be much bigger than the ones we see around today. They were significantly larger than the ones depicted in the previous section.

The largest of all the giant bugs of prehistory, Meganeuropsis permiana, is the huge distant relative of the dragonflies we see today. It could grow to have a wingspan of 28 inches. From head to tail it measured 17 inches.

Researchers have discovered one reason why insects were once dramatically larger than they are today. “More than 300 million years ago, there was 31 to 35 percent oxygen in the air,” according to a lead researcher. “That means that the respiratory systems of the insects could be smaller and still deliver enough oxygen to meet their demands, allowing the creatures to grow much larger.

Although millipedes aren’t technically insects [they’re arthropods like lobsters or scorpions] the Arthropluera is worth a mention.

How big do you think Arthropluera was? Seven inches? Eight? Think closer to nine feet.

These giant giant arthropods ranged in size from one foot to eight and one-half feet. Like the mega-cockroach, Arthropluera lived in the Carboniferous period and was the largest known land invertebrate that ever roamed planet Earth.

Further reading and references:


Current research into our insectoidal friends suggests they are brighter than we had once thought. Indeed, they are neither mindless or of zero intelligence. Insect brains are tiny, but their miniature neural networks nevertheless hold lessons for artificial intelligence and robotics. They even illustrate how human brains operate and the very nature of intelligence.
Research has shown how insect brains employ clever behavioral shortcuts to perform complex cognitive functions with minimal neural circuitry.
Amazingly, insects even manufacture tools, and some employ a wide range of strategies to create traps, projectiles, bridges and even amplifiers to project mating calls.
So could insects become super intelligent – enough to conquer universal distances or other dimensions? It would seem given the right conditions that insects could certainly move beyond mere survival mode to something more creative. And then, given lots of time and patience – who knows?


Intelligent Insects

Smart Bugs

Insect Consciousness

Read Next

Merry Christmas and a Happy 2021

Merry Christmas to all readers and writers and a Peaceful and Healthy 2021. Season’s Greetings to all. Have a lovely Christmas and a Great New Year. And let’s see the back of this wretched virus. There’s no denying that 2020 has been a terrible year for the world, but now is the time to look…

Continue Reading