Geographic Seahare (Siphonota geographica) are related to nudibranchs, are generally a bit larger than most nudis, and they have not quite abandoned the shell of their snail ancestors but rather have kept it internally.
Geographic Seahare
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Geographic Seahare (Siphonota geographica) are related to nudibranchs, are generally a bit larger than most nudis, and they have not quite abandoned the shell of their snail ancestors but rather have kept it internally.