Incredibly Large Invertebrates

When we think about invertebrates, we picture the pesky cockroach, a buzzing mosquito or the annoying fly. But the world of invertebrates is not tiny, as a matter of fact, there are animals without a backbone which are much longer than an African elephant.  Read on to explore more about these fascinating invertebrates.

Goliath Birdeater & Giant Huntsman Spider

Animal kingdom classification places spiders under the class Arachnid, with an estimated  46,000 species currently identified till date. The largest among the arachnids by weight is the  Goliath birdeater, a spider that weight almost as much as a hamster – at 170 grams or 0.3 pounds. However, when the total leg span is considered, the title of the largest spider goes to the Giant Huntsman spider, having a leg span of 12 inches. This fear-inducing arachnid is so big that people compare it to the size of dinner plates.

African Giant Earthworm

Earthworms are generally thought to be small, docile animals, mostly out of sight and underground. However, the African giant earthworm or Microchaetus rappi is much larger than your average garden-variety earthworm. It is known to grow more than 22 feet long, which is much longer than any human. Also, this worm weighs in at around 1,500 grams or 3.3 pounds, which is heavier than most newborn dogs. Thankfully, this squirming behemoth does not pose a threat to humans, in fact, like most other species, they improve soil fertility.


Dragonflies are rather small, with most species being 1 to 4 cm in length. But travel back in time to the Permian Era, 299 million years ago, and you might just be unfortunate enough to meet one of the largest predatory flying insects ever. Commonly called as griffinflies, these prehistoric dragonflies were true giants among the insect worlds measuring in at 17 inches in length, from head to tail and sporting a wingspan of over 27 inches. Besides having the largest wing in the insect world, griffinflies also had very sharp mandibles which were extremely apt for its predatory lifestyle. Scientists theorize that the reason these insects got so big was because primitive earth had a much higher level of oxygen compared to today. So, it would be impossible for these insects to survive in our modern day atmosphere.

Mesonychoteuthis hamiltoni

Squids are soft-bodied invertebrates beloning to the class Cephalopoda. Most species average from 2 cms to 2 feet in length. But one particular species of cephalopod grows much, much larger – the Colossal squid or Mesonychoteuthis hamiltoni. A fully grown, adult collosal squid can grow up to 45 feet in length, which is taller than 2 giraffes stacked on top of each other. They also weight almost 500 kgs when alive. Usually, colossal squids are deep sea creatures and are rarely seen out in the open ocean. Therefore, many people considered them to be more of a supernatural entity or a sailor’s myth until the very first proof of their existence was documented – in the form of two tentacles found in the stomach of a sperm whale, circa 1925.  

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