What is the largest arachnid that has ever lived? -

The term “arachnids” probably conjures up visions of spiders: from creepy, creepy things spinning silently from webs in the corner of the room to large, hairy creatures with fangs – like the mythical Shelob or Aragog – stalking you in the dark. . But just how big (and fierce) can these arachnids get? Better yet, who was the greatest to have ever lived?

Answering this question is deceptively simple. Arachnids are eight-legged arthropods, which means that this group contains not only spiders but also scorpions and ticks among others, much smaller and rarer groups. Of these, spiders are the most diverse group of arachnids (the 50,000th species was recently discovered, and this number should increase). The problem is that exactly what counts as an arachnid is a bit of an open question.

Arachnids are part of a larger group of arthropods called chelicerae. The chelicerae are subdivided into smaller groups, with the arachnids being one group and the horseshoe crabs (in the order Xiphosura) and sea scorpions (Eurypterida) being separate but related to the arachnids.

According to Russell Bicknell, a paleontologist at the University of New England in Australia, this is the traditionally accepted phylogeny. But one paper came out recently that suggested that was wrong, and suggested that horseshoe crabs and sea scorpions actually nest in arachnids.”

Related: Why do Cambrian creatures look so weird? The Eurypterids, shown here in this illustration, were the largest species of arachnid to ever live, rivaling humans in size.

The Eurypterids, shown here in this illustration, were the largest species of arachnid to ever live, rivaling humans in size. (Image credit: estt/Getty Images)

Thomas Hegna, assistant professor of paleontology at the State University of New York (SUNY) in Fredonia, who was not involved in the new study, told Live Science in an email that the new phylogeny, based on molecular analysis, implies some terrestrial chelicerae groups (spiders and scorpions) predated marine groups (horseshoe crabs and sea scorpions). However, despite the fact that this claim is well supported by genetic evidence, it is inconsistent with the fossil record.

This may sound like paleontological pedantry, but it actually makes a huge difference when it comes to determining the largest arachnid of all time.

According to the traditional view of the arachnid family tree (ignoring horseshoe crabs and sea scorpions), the largest living arachnid is probably a spider.

There are two spiders that make great contenders for the title of “World’s Largest Spider”. The largest known spider by mass is the Goliath Bird Eater (Theraphosa blondi)a 6-ounce (170-gram) spider whose body can reach up to 5 inches (12 centimeters) in length, a number that reaches 11 inches (28 cm) when its legs are included, according to the American Association for the Advancement of science (AAAS).

If one is to judge the size of a spider instead by the diameter of its leg span, then the largest spider could very well be the giant hunter spider (Maxima heteropodslisten)), which has a leg span of about 1 foot (30 cm) in diameter, making it about the size of a dinner plate. Despite its size, this spider was only discovered in 2001.

When we delve into the fossil record, we find that the largest arachnid of all time was probably not a spider, but a scorpion. Brontoscorpion anglicus was a scorpion that lived during the Silurian-Devonian era (between 350 million and 450 million years ago) and reached lengths of almost 3 feet (1 m) long – five times longer than the longest living scorpion today. However, the caveat here is that the only example of this species was described from a single fossilized finger, so the true size of the animal is an educated guess.

Related: Is each spider web unique?

These animals are the largest known arachnids, both living and extinct, as arachnids are traditionally defined. But if sea scorpions and the horseshoe crab are indeed considered arachnids, as new research might suggest, then the largest living arachnid is no longer a spider, but rather a horseshoe crab.

The largest living species of horseshoe crab, Tachypleus tridentatus, could reach 31 inches (79.5 cm) in diameter.

The largest living species of horseshoe crab, Tachypleus tridentatus, could reach 31 inches (79.5 cm) in diameter. (Image credit: Jaap Bleijenberg / Alamy)

The largest living species of horseshoe crab surpasses the largest living spiders. Tachypleus tridentatus, the largest of this group, can reach heights of 31 inches (79.5 cm) and weigh up to 9 pounds (4 kilograms), according to a 2017 study published in the Asia-Pacific Biodiversity Journal.

As for the largest species of all time, the title would likely go to a member of the now-extinct sea scorpions, a group scientifically known as the eurypterids. Fossils suggest that many of these ancient marine predators even rival humans in size.

The largest species in this group was Jaekelopterus rhenaniae, a species discovered in 2007 that had claws up to 18 inches (46 cm) long. From the claws, researchers estimated that its body was about 8 feet (2.5 m) long, making it not only the largest potential arachnid, but the largest member of the entire group that contains spiders. arachnids, chelicerae.

Originally posted on Live Science.

#largest #arachnid #lived

Please follow and like us:

‘Fish Lizard’ Fossils Found In The Swiss Alps Belonged To Some Of The Largest Creatures That Ever Lived

Byadmin April 29, 2022

The fossils belong to three ichthyosaurs, and they may have been among the largest animals to ever live on Earth, according to a new study. Ancient creatures could reach 80 tons and 65 feet (20 meters) in length, rivaling modern sperm whales. These “fish lizards” first appeared in the ocean about 250 million years ago,…

Science

These meteorites contain all the building blocks of DNA

Byadmin April 28, 2022April 29, 2022

Three meteorites contain the molecular building blocks of DNA and its cousin RNA, scientists have recently discovered. A subset of these building blocks had previously been detected in meteorites, but the rest of the collection seemed mysteriously absent from space rocks – until now. The new discovery supports the idea that around four billion years…

Science

In a first, scientists observe actions spiders use to escape sexual cannibalism

Byadmin April 25, 2022

In the animal world, there are examples of creatures that use extremely fast speeds to capture prey – or avoid being captured. Now, for the first time, scientists have observed the use of ultra-fast action in a very specific scenario: as a means of escaping sexual cannibalism. Scientists have discovered male spiders of the species…

Science

Time may not exist – but that’s okay

Byadmin April 24, 2022

Does time exist? The answer to this question may seem obvious: of course it is! Just look at a calendar or a clock. But developments in physics suggest that the non-existence of time is an open possibility, and one that we should take seriously. How is that possible, and what would that mean? It will…

Science

Could the blueprint of life have been generated in asteroids?

Byadmin April 26, 2022

Conceptual image of meteoroids supplying nucleobases to ancient Earth. Nucleobases are shown as structural diagrams with hydrogen atoms as white spheres, carbon as black, nitrogen as blue, and oxygen as red. Credit: NASA Goddard/CI Lab/Dan Gallagher Using new analysis, scientists have just found the last two of five DNA and RNA information units that had…

Science

Time may not exist at all, according to physics

Byadmin April 25, 2022

Does time exist? The answer to this question may seem obvious: Of course yes! Just look at a calendar or a clock. But developments in physics suggest that the non-existence of time is an open possibility, and one that we should take seriously. How is that possible, and what would that mean? It will take…

Cookie	Duration	Description
cookielawinfo-checkbox-analytics	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-functional	11 months	The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-others	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance	11 months	This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy	11 months	The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.

Similar Posts

Leave a Reply Cancel reply

Follow Us