• Email Us: [email protected]
  • Contact Us: +1 718 874 1545
  • Skip to main content
  • Skip to primary sidebar

Medical Market Report

  • Home
  • All Reports
  • About Us
  • Contact Us

The Giant Joro Spider: How Big Are They And Why Are They Spreading?

August 21, 2024 by Deborah Bloomfield

Joro spiders have a lot about them that might get an arachnophobe’s back up. They can parachute, they can be massive, they have venom, and are spreading far out of their native range. However, they’re also shy, play dead, and can be bested by a turkey baster.

Joro spider venom only poses a threat to their prey, which mostly consists of mosquitoes, stink bugs, and other small insects. And while most people might think twice about a parachuting arachnid, the truth is this ballooning behavior only happens when they’re little, and it’s widespread among spiders.

Meet the joro spider

Known to science as Trichonephila clavata, the joro spider gets its name from the Japanese jorō-gumo meaning “entangling bride,” and they’re steeped in folklore. 

Female joro spiders have a vibrant coloration of yellow with black stripes and a red spot on their abdomens, while the males are a more subdued hue of reddish-brown. They’re native to East Asia but have been making headlines for their impressive spread across the United States in recent years, where they are an invasive species.

joro spider size in female versus male, the female is much bigger

Joro spider size varies significantly across the sexes, with females being much larger than males.

Image credit: Brandon Iwamoto / Shutterstock.com

How big are joro spiders?

Joro spiders can be the size of an outstretched human hand, with a leg span of up to 10 centimeters (4 inches). However, there’s vast sexual dimorphism in the species, with the males having a body size less than a quarter of that of the females.

Why is the joro spider spreading?

Since it was first discovered in Georgia, USA in 2014, the joro spider has spread to several other states across the US. The pattern of their spread since their initial introduction appears to be in line with natural migration, facilitated by their ballooning behaviors as spiderlings to take to the skies. Although, it’s also possible they may have been hitchhiking along on some human road trips.

Advertisement

One possible explanation for their nomadic nature could come down to their stress response. A recent study looked at how they reacted physiologically to the non-fatal stressor of being restrained, and found that the joro spider remained much more calm with less variation in heart rate compared to other spider species.

This may be connected to their reputation for playing dead far longer than other spider species. And it’s possible that their chilled approach to stressful situations enables them to occupy environments with frequent disturbances, places that other spiders’ delicate hearts simply couldn’t tolerate.

joro spider in a web with lots of prey wrapped up

Joro spiders are super deadly… if you’re an insect.

Image credit: Surapong Kaewsa-ad / Shutterstock.com

Are joro spiders dangerous?

These laid-back arachnids aren’t dangerous to humans, as although they are venomous, they’re also unlikely to bite us because they are so shy. Furthermore, they have very small fangs designed for biting insects, not mammals. That means they’re unlikely to break the skin and even if they did, the venom wouldn’t be considered medically important for a human. A joro spider bite is compared by PennState Extension to a weak bee sting, and in 2022, they found no reports of an allergic reaction to a joro spider bite.

Advertisement

So it just goes to show, don’t read a spider by its headlines. Especially not one who can be made to play dead with nothing more than a puff of air from a turkey baster.

Deborah Bloomfield
Deborah Bloomfield

Related posts:

  1. Pakistan minister says threat to NZ cricket team originated in India
  2. Australian law chief wants defamation rules fixed for the internet age – letter
  3. Deep-Ocean Plutonium Hints At A Nearby Kilonova 3-4 Million Years Ago
  4. How To Watch The Historic First Launch Of Ariane 6

Source Link: The Giant Joro Spider: How Big Are They And Why Are They Spreading?

Filed Under: News

Primary Sidebar

  • Unethical Experiments: When Scientists Really Should Have Stopped What They Were Doing Immediately
  • The First Humans Were Hunted By Leopards And Weren’t The Apex Predators We Thought They Were
  • Earth’s Passage Through The Galaxy Might Be Written In Its Rocks
  • What Is An Einstein Cross – And Why Is The Latest One Such A Unique Find?
  • If We Found Life On Mars, What Would That Mean For The Fermi Paradox And The Great Filter?
  • The Longest Living Mammals Are Giants That Live Up To 200 Years In The Icy Arctic
  • Entirely New Virus Detected In Bat Urine, And It’s Only The 4th Of Its Kind Ever Isolated
  • The First Ever Full Asteroid History: From Its Doomed Discovery To Collecting Its Meteorites
  • World’s Oldest Pachycephalosaur Fossil Pushes Back These Dinosaurs’ Emergence By 15 Million Years
  • The Hole In The Ozone Layer Is Healing And On Track For Full Recovery In The 21st Century, Thanks To Science
  • First Sweet Potato Genome Reveals They’re Hybrids With A Puzzling Past And 6 Sets Of Chromosomes
  • Why Is The Top Of Canada So Sparsely Populated? Meet The “Canadian Shield”
  • Humans Are In The Middle Of “A Great Evolutionary Transition”, New Paper Claims
  • Why Do Some Toilets Have Two Flush Buttons?
  • 130-Year-Old Butter Additive Discovered In Danish Basement Contains Bacteria From The 1890s
  • Prehistoric Humans Made Necklaces From Marine Mollusk Fossils 20,000 Years Ago
  • Zond 5: In 1968 Two Soviet Steppe Tortoises Beat Humans To Orbiting Around The Moon
  • Why Cats Adapted This Defense Mechanism From Snakes
  • Mother Orca Seen Carrying Dead Calf Once Again On Washington Coast
  • A Busy Spider Season Is Brewing: Why This Fall Could See A Boom Of Arachnid Activity
  • Business
  • Health
  • News
  • Science
  • Technology
  • +1 718 874 1545
  • +91 78878 22626
  • [email protected]
Office Address
Prudour Pvt. Ltd. 420 Lexington Avenue Suite 300 New York City, NY 10170.

Powered by Prudour Network

Copyrights © 2025 · Medical Market Report. All Rights Reserved.

Go to mobile version