Thylacocephala

Extinct group of arthropods

Thylacocephala (from the Greek θύλακος or thylakos, meaning "pouch", and κεφαλή or cephalon meaning "head") is an extinct group of mandibulate arthropods, that are generally regarded as a kind of crustacean, though their exact position within this group is uncertain. As a class they have a short research history, having been erected in the early 1980s. They typically possess a large, laterally flattened carapace that encompasses the entire body.

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