【摘 要】
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The rapid rise of arthropods during the Cambrian quickly established some dades,such as the euarthropod stem-group called Radiodonta,as the dominant and most di
【机 构】
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Shaanxi Key Laboratory of Early Life and Environment, The Key Laboratory of Continental Dynamics, De
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The rapid rise of arthropods during the Cambrian quickly established some dades,such as the euarthropod stem-group called Radiodonta,as the dominant and most diverse predators in marine ecosystems.Recent discoveries have shown that the size and dietary ecology ofradiodontans are far more diverse than previously thought,but little is known about the feeding habits of juveniles.Here,we document a very small (～18-mm-long),near-complete specimen of the radiodontan Lyrarapax unguispinus from the early Cambrian Chengjiang Biota of China.Tnis specimen is the smallest radiodontan individual known,representing a juvenile instar.Its adult-like morphology-especially the fully developed spinose frontal appendages and tetraradial oral cone-indicates that L.unguispinus was a well-equipped predator at an early developmental stage,similar to mode raptorial euarthropods,such as mantises,mantis shrimps and arachnids.This evidence,coupled with the basal phylogenetic position of radiodontans,confirms that raptorial feeding habits in juvenile euarthropods appeared early in the evolutionary history of the group.
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