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Anomalocaridids

Anomalocaridids (members of the extinct arthropod family Anomalocarididae) are marine animals largely found in Cambrian deposits, including rocks from the USA, Canada, Poland,  China,  and Australia. Current evidence suggests they went extinct sometime after the Devonian period. They were large animals, some may have been up to 2 m (7 ft) in length, and were most likely active predators.

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