A recently discovered spider species in Australia, the ballista spider, creates snare traps specifically designed to catch green tree ants, boasting accelerations that can inflict over 130 times the force of gravity—enough to fatally impact humans.

Researchers recorded accelerations reaching 1367 m/s as the green tree ants, Oecophila smaragdina, trigger the web’s snare trap.

“To capture this incredible moment, I had to set my camera to 5,000 to 7,000 frames per second,” explains Ajay Narendra from Macquarie University, Sydney. “Such high-speed photography was unprecedented in my years of wildlife documentation.”

In 2022, Greg Anderson of the QIMR Berghofer Institute in Brisbane, Australia, observed the remarkable behavior of green tree ants jumping into the spider’s traps in far north Queensland. However, without specialized camera gear, he could only see a blur of prey being ‘ballistically’ launched from the peculiar conical nests.

In early 2023, alongside Pranav Joshi, also from Macquarie University, Narendra dedicated ten days to studying and photographing these nocturnal spiders belonging to the Arachnida family, yet to receive a scientific name: Propostilla.

The term “ballista spider” comes from the Roman crossbow-like weapon known for launching large projectiles over long distances.

These spiders hide beneath leaves during the day and construct their traps just after dusk, a process that can take up to four hours. They skillfully tie together 15 to 60 tightly bundled tension lines attached to the leaves, forming a cone.

After constructing the trap, the spider employs a chemical to entice green tree ants while sparing other ant species, prompting them to attack the snare with their mandibles.

“The silk appears quite sticky,” notes Narendra. “The ants’ mandibles struggle to release as they inadvertently get glued together.”

In their attempts to escape, the ants inadvertently trigger a tension wire, launching them nearly 30 centimeters into the air, where they become ensnared in the spider’s main web.

This tactic likely serves to elevate the prey above the forest floor, minimizing the risk of counterattacks from the ant colony, explains Narendra.

Although it may seem laborious for the spider to create a trap for each meal, green tree ants present a dependable food source. “The spider simply builds a web, and food arrives,” he adds.