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The superfamily Aplysioidea is a superfamily of mostly rather large sea slugs, marine gastropod mollusks in the clade Aplysiomorpha within the informal group Opisthobranchia. This superfamily contains only one family, the Aplysiidae; the sea hares. 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 sitting rabbit or hare. Sea hares are however shell-less sea snails, and some species are extremely large. The Californian black sea hare, ''Aplysia vaccaria'' is arguably the largest living gastropod species, and is certainly the largest living shell-less gastropod. In Australia sea hares are sometimes known as "beach blobbies". Sea hares do sometimes become stranded on beaches, and when this happens, they contract as much as possible to minimize desiccation, and when the sea hare's body is not fully supported by water, the rhinophores collapse and the animal looks more blob-like. == Description == Members of the Aplysiidae have an atrophied inner shell (in contrast with the nudibranchs, which have no shell at all). In ''Aplysia'' and ''Syphonota'', this shell is a soft flattened plate over the visceral rear end, where it is fully or partially enclosed in the mantle skin. In ''Dolabella auricularia'', the shell is ear-shaped. The shell is only present in the larval stage of the two genera ''Bursatella'' and ''Stylocheilus'', and on this basis they have been grouped into the subfamily Dolabriferinae. They are rather large animals. Their length varies between 20 cm and 75 cm (''Aplysia vaccaria''), and they can weigh well over 2 kg. They are cosmopolitan and found in temperate and tropical seas, inhabiting shallow coastal areas and sheltered bays, thick with vegetation. The Aplysiidae are herbivorous, eating a variety of red, green or brown algae and eelgrass. Their color is diet-derived from the pigments of the algae. They concentrate the toxins found on algae. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Aplysiidae」の詳細全文を読む スポンサード リンク
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