Aplysiida

Order of gastropods

The order Aplysiida, commonly known as sea hares (Aplysia species and related genera), are medium-sized to very large opisthobranch gastropod molluscs with a soft internal shell made of protein. These are marine gastropod molluscs in the superfamilies Aplysioidea and Akeroidea. The common name "sea hare" is a direct translation from Latin: lepus marinus, as the animal's existence was known in Roman times.

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