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Desmopteridae

Desmopteridae is a family of pelagic sea snails or "sea butterflies", marine gastropod mollusks in the superfamily Cymbulioidea.

This family has no subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).

Desmopterus Chun, 1889 is the type genus of the family Desmopteridae.

The species are protandric hermaphrodites. There is no shell, no protoconch and no longer any supporting tissue. The body consists almost completely of the two big parapodia (winglike flaps).