A newly discovered species of spider in the remote rainforests of northern Australia has developed a remarkable hunting strategy, utilizing a tension-based silk trap that functions like a catapult to capture prey. This specialized method allows the spider to target and capture ants, which are considered unusually dangerous and difficult prey for arachnids.
The spider, nicknamed "ballista" by researchers after an ancient projectile weapon, lives in the tropical rainforests of northern Queensland. Scientists from Macquarie University observed the spider constructing a unique trap over several nights, using high-speed and infrared cameras. The spider creates a cone-shaped scaffold of dozens of tensioned silk lines. When a target, identified as the aggressive green tree ant (Oecophylla smaragdina), approaches and interacts with the trap, it triggers the mechanism. The resulting release of tension propels the ant into the spider's main web with extreme acceleration, described by lead researcher Prof. Ajay Narendra as "15 times the most extreme g-forces experienced by jet pilots."
Researchers believe this highly specialized hunting method evolved as a defense mechanism against the aggressive nature of its prey. Ants, especially certain species, possess chemical defenses such as stings and can quickly summon reinforcements to overwhelm predators. The ballista spider's trap allows it to capture a single, potentially hazardous ant from a safe distance, pulling it away from ant trails and nests.
The spider spends its days in hidden webs beneath leaves and ventures out at night. After dark, it descends from its resting place to construct the trap, anchoring itself with a silk line before meticulously building the tensioned web. The findings were published in the journal Current Biology.