Ant attack! Newly discovered spider uses ingenious 'catapult' to catch prey.

Ant attack! Newly discovered spider uses ingenious 'catapult' to catch prey. A newly discovered spider species in the rainforests of northern Queensland has developed an extraordinary hunting strategy by using a spring-loaded silk catapult to capture ants. Researchers say the nocturnal arachnid, nicknamed the "ballista spider", appears to specialise exclusively in hunting the aggressive green tree ant (Oecophylla smaragdina). Its prey are usually off limits for most spiders due to their aggressive behaviour and use of chemical defences. They can rapidly summon large numbers of nestmates through alarm signals, making them potentially dangerous for solitary predators. However, the ballista spider conceals itself above ant foraging routes. After nightfall, it constructs an elaborate trap anchored to nearby vegetation or the forest floor. The spider may spend up to four hours creating the structure, which consists of dozens of tensioned silk strands arranged in a cone-shaped bundle close to the ground. When a green tree ant approaches, it reacts aggressively to the structure, biting the cone and inadvertently detaching it from its anchor point. The release triggers the trap, causing the tensioned silk to snap upwards and propel the ant more than 30 centimetres into the spider's web. The trap functions as a biological catapult, storing elastic energy within the silk before releasing it almost instantaneously - and taking the tree ant away from a trail where it may be overwhelmed.