This Tiny Australian Spider Builds a Catapult That Launches Ants Into the Air

A Web Unlike Any Other

When most silk-spinning spiders hunt, they build a web and wait for prey to blunder into it. But a newly discovered species from Australia instead uses its silk to craft a spring-loaded, cone-shaped death trap — one that catapults its prey directly into the spider's main web. The find has stunned researchers, and the details are almost hard to believe.

In an unprecedented example of hunting specialization, this nocturnal rainforest spider has evolved a silk-powered snare that targets just one species of ant, launching its prey into the air with astonishing power and speed. A detailed description of the spider's predatory strategy and mechanics was published on June 22, 2026, in the journal *Current Biology*.

Meet the Ballista Spider

The spider — nicknamed the "ballista spider," after a projectile weapon that originated in ancient Greece — has gangly, orange limbs and a greenish-yellow body measuring about 0.2 inches (5 millimeters) long. It was first observed by Professor Greg Anderson, a biomedical research scientist who is also a spider taxonomist and photographer. Researchers from Macquarie University in Australia and the University of Greifswald in Germany studied the ballista spider's trap mechanism in its natural environment and tested the durability of its silk.

Their team spent 10 nights in the tropical rainforests of northern Queensland, capturing the spider's behavior using high-speed and infrared cameras. What they recorded was a masterclass in biological engineering. As night falls, the spider descends 50 centimeters or more to lay an anchor point on a leaf, a branch, or the forest floor, then spends up to four hours engineering a vertical arrangement of 15 to 60 silk tension lines bundled together in a cone near the ground. The spider then wraps the cone with a thinner type of silk, then rapidly retreats upward, holding onto the thread until the right ant arrives.

The Trap Is Triggered by the Prey Itself

When a green tree ant becomes stuck to the cone, it attempts to free itself by biting the silk. Unknowingly, this action triggers the snare. Launched with an acceleration exceeding 4,265 feet per second squared, the ant is flung into the predator's net about 12 inches above, where it is quickly devoured once fully entangled. The snare's "exceptionally high power" flings the ant into a bigger web at "15 times the most extreme g-forces experienced by jet pilots," said lead researcher Professor Ajay Narendra.

This seems to be the only case where a spider's web is designed to catch a single prey species, and where the mechanism is triggered by the prey rather than by the predator. Researchers also suspect the spider is playing a chemical trick. One possibility, according to the study, is that the spiders apply pheromones to the silk catapult that provoke only green tree ants, causing them to attack the cone and trigger its release. When researchers released other nocturnal ant species present on the same tree near the cone while the spider remained in its waiting position, all three species walked close to the cone but did not react to it — further evidence that something in the silk is speaking directly to the green tree ant's instincts.

Why Target Such a Dangerous Prey?

It's very unusual for a spider to feed on ants, because they're notoriously dangerous. Ants have a range of chemical defenses — including the ability to sting in some species — and they use alarm signals to rapidly recruit hundreds and even thousands of other ants as backup to overcome potential predators. The ballista spider's solution to this problem is elegant: don't just catch the ant, remove it from the battlefield entirely. Its highly specialized strategy likely evolved to take advantage of the ant's natural aggression and then overcome its defenses; the slingshot mechanism flings the ant from the foraging trail, reducing the risk that the spider will be swarmed by other workers.

Gram for gram, the webs store more energy and exert more power than any known biological catapult. Green tree ants are abundant — up to five million workers in a single arboreal nest — making them a reliable resource all year round. For a tiny spider with a very specific appetite, that's an all-you-can-eat buffet just waiting to be outsmarted. As researchers work toward formally naming the species, the ballista spider stands as a remarkable reminder that evolution's most creative inventions are often hiding in the dark, in rainforests we've barely begun to explore.