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Abstract
The biomechanics underlying the predatory strike of dragonfly larvae is not yet understood. Dragonfly larvae are aquatic ambush predators, capturing their prey with a strongly modified extensible mouthpart. The current theory of hydraulic pressure being the driving force of the predatory strike can be refuted by our manipulation experiments and reinterpretation of former studies. Here, we report evidence for an independently loaded synchronized dual-catapult system. To power the ballistic movement of a single specialized mouthpart, two independently loaded springs simultaneously release and actuate two separate joints in a kinematic chain. Energy for the movement is stored by straining an elastic structure at each joint and, possibly, the surrounding cuticle, which is preloaded by muscle contraction. As a proof of concept, we developed a bioinspired robotic model resembling the morphology and functional principle of the extensible mouthpart. Under