Sea butterflies, also known as Thecosomata or flapping snails, are a taxonomic order of pelagic swimming sea snails, holoplanktonic opisthobranch gastropod mollusks in the order Thecosomata (Blainville, 1824).
Sea butterflies are a taxonomic order of pelagic swimming sea snails. Sea butterflies is also known as Thecosomata or flapping snails. Pelagic swimming sea snails are holoplanktonic opisthobranch gastropod mollusks in the order Thecosomata (Blainville). Blainville is 1824.