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.

Sea hares, classified as Anaspidea, are a type of marine gastropod mollusk, a member of the diverse snail family. Its name comes from its rabbit-like appearance, with two head structures called rhinophores resembling hare ears. Sea hares can be found in different parts of the world.

Anaspids were small marine fish that lacked a heavy bony shield and paired fins, but were distinctively hypocercal. Compared to many other ostracoderms, such as the Heterostraci and Osteostraci, anaspids did not possess a bony shield or armor, hence their name.

Anaspidea The Aplysidae have tentacles (rhinophores) shaped like the ears of rabbits, from which they get their common name, "sea hares." Commonly behind the head is a neck-like region that merges into a plump trunk.

Aplysiidae is the only family in the superfamily Aplysioidea, within the clade Anaspidea. [1] These animals are commonly called sea hares because, unlike most sea slugs , they are often quite large, and when they are underwater, their rounded body shape and the long rhinophores on their heads mean that their overall shape resembles that of a ...

The clade Anaspidea, 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.

Other articles where Anaspidea is discussed: gastropod: Classification: Order Anaspidea Shell reduced to flat plate; feed on large seaweed rather than microscopic algae; sea hares (Aplysiidae); 1 other small family.

Anaspidea. Accessed through: Costello, M.J.; Bouchet, P.; Boxshall, G.; Arvanitidis, C.; Appeltans, W. (2021) European Register of Marine Species at: https://marbef.org/data/aphia.php?p=taxdetails&id=171 on 2025-04-13

Jun 8, 2020 · The Clade for the sea hare is Anaspidea. This term is derived from Greek and means "without a shield", and refers to the fact that sea hares do not have an external shell, only an internal one made of protein.

Three sea hares, representing two families, are common in Norway; Aplysia punctata, Elysia viridis and Akera bullata.