Spiders are arachnids that are best known for their distinctive eight-legged appearance. There are around 50,000 different species of spiders that are recognized today. They are found everywhere in the world except Antarctica, and they have adapted to live in a wide variety of habitats. As there are so many different species, it’s not surprising that spiders can be vastly different sizes. The smallest spider in the world has a minuscule body, barely the size of a pinhead, but just how big is the biggest? Join us as we discover the absolute largest spider in history!
All about Spiders
Spiders are arachnids from the Araneae order, which are characterized by their eight legs and the ability to produce intricate webs made from silk. Araneae is the largest arachnid order and contains around 130 different family groups. Spiders are known for their diversity and their ability to survive and thrive in a vast range of habitats. Their color tends to help them to do this. This is because many species share the same color as their main habitat so that they can blend in easily and avoid predators. Spiders also vary in size all the way from the tiniest Pata digua spider, which is only 0.015 inches long, up to the famous tarantulas, which can have a body the size of a human hand.
Although it’s commonly assumed that all spiders capture their prey using their web, different species use different methods. While some do use their webs to catch prey, others are ambush predators, while others mimic plants or even ants. Depending on the size of the spider, prey can be anything from tiny insects up to birds or rodents. Almost all spiders have two hollow fangs, which they use to inject venom into their prey. However, the majority of spiders are not actually considered to be dangerous to humans. This is because most have venom that is too weak to do any harm.
Spiders reproduce by laying eggs, and females can lay several hundred eggs at one time. Incredibly, females then wrap their eggs in an egg sac which she either leaves in the web or carries around everywhere she goes. Depending on the species, this egg sac can be as large as a tennis ball!
The Largest Spider in History
The absolute largest spider in history is the Goliath bird eater (Theraphosa blondi), which is the largest spider alive today by length and weight. It weighs around 6.2 ounces and can reach body lengths of up to an incredible 5.1 inches – easily making it one of the most fearsome and intimidating spiders in the world. It also has a leg span of up to 11 inches and is typically a light brown or tan color. Goliath birdeaters are native to South America – particularly the Amazon rainforest – and live in burrows near marshes or swamps.
Goliath bird eaters are a member of the tarantula family and have fangs between 0.8 and 1.5 inches long. Although they are venomous, they are not considered to be dangerous, with their bite likened to a wasp sting. Despite their name, Goliath birdeaters don’t typically prey entirely on birds. Instead, they prefer to eat a range of insects, lizards, frogs, and mice. Once they’ve caught their prey, they drag it back to their burrow to eat. However, they don’t just tuck straight in. Instead, these massive spiders inject toxins into their prey which liquefies its insides. They just literally suck everything out of it, which only adds to their fearsome reputation.
Although goliath bird eaters don’t have a particularly strong venom, they do have an effective – if rather unusual – defense mechanism…they launch bristles at predators! This surprising action can be harmful to both the skin and mucous membranes. However, it is usually only used as a last resort. Goliath bird eaters also rub their hairs together to create a loud hissing noise. This can be heard as far away as 15 feet!
What about Leg Span?
Although goliath bird eaters are considered to be the largest spiders in the world, giant huntsmans just manage to beat them for leg span. Giant huntsmans have a massive one-foot leg span, and their legs are incredibly long compared to their bodies. Giant huntsmans are the largest among the huntsman spiders. However, their bodies themselves are only small at 1.8 inches long.
Giant huntsmans are native to Laos, where they tend to dwell in caves – typically near cave entrances. They don’t catch their prey on webs. Instead, they utilize their long legs and chase down their prey. Their diet generally consists of anything smaller than them that they can catch and eat.
The Largest Spider that Never was
If the thought of the goliath bird eater isn’t already terrifying enough, then imagine a beast more fearsome than any spider in existence. Imagine a spider with a foot-long body and a leg span of a foot and a half. Discovered in a 300 million-year-old rock from Argentina, Megarachne servinei was coined as the largest spider that had ever existed, and indeed it was…until it wasn’t.
From its discovery in 1980 until 2005, Megarachne servinei was widely known as the largest spider ever. Despite appearing to be spider-like, scientists couldn’t pinpoint why it lacked certain distinctive spider characteristics. However, in 2005 another Megarachne specimen was discovered, and after much study, the truth was finally known. Incredibly, rather than being a giant spider, Megarachne is actually a previously unknown sea scorpion. This revelation quickly reinstated the goliath bird eater back to the status of the largest spider and rewrote the history books.
With the reclassification of Megarachne, the largest known extinct spider – and the largest fossilized spider – is now Nephilia jurassica. Nephilia jurassica is closely related to the existing golden orb weaver spiders and dates back 165 million years. However, compared to the spider that never was – and indeed the largest spiders today – Nephilia jurassica was nowhere near giant size. Instead, they had 1-inch bodies and a 5-inch leg span. This means that goliath bird eaters look set to keep their position at the top for the foreseeable future.
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