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Heterostraci

plural noun
Het·​er·​os·​tra·​ci

Definition of Heterostraci

: a class or other division of ostracoderms with widely separated nares and eyes and with an exoskeleton which may consist of a few large plates or numerous placoid scales

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History and Etymology for Heterostraci

New Latin, from heter- + Greek ostrakon shell, potsherd

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