Desmopteridae is a family of pelagic sea snail

Sea snail

Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....

s or "sea butterflies", marine

Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 gastropod mollusks in the superfamily Cymbulioidea

Cymbulioidea

Cymbulioidea is a taxonomic superfamily of pelagic "sea butterflies". These are holoplanktonic opisthobranch molluscs in the clade Thecosomata.-Anatomy:...

.

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

Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005)

The taxonomy of the Gastropoda as it was revised by Philippe Bouchet and Jean-Pierre Rocroi is currently the most up-to-date overall system for classifying gastropod mollusks...

).

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

The species are protandric hermaphrodites

Hermaphrodite

In biology, a hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes.Many taxonomic groups of animals do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both...

. There is no shell, no protoconch

Protoconch

A protoconch is an embryonic or larval shell of some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod...

 and no longer any supporting tissue. The body consists almost completely of the two big parapodia (winglike flaps).

Species

Species within the genus Desmopterus include:

• Desmopterus cirropterus Gegenbaur, 1855
• Desmopterus gardineri Tesch, 1910 - Distribution: Indian Ocean.
• Desmopterus pacificus Essenberg, 1919 - Distribution: California, Oceanic. Description: shorter wing plate tentacles.
• Desmopterus papilio Chun, 1889 Distribution: Seychelles, Florida, Bermuda, Venezuela, Brazil, Adriatic Sea, tropical and subtropical oceanic waters. Length: body length between 0.5 – 2.0 mm, swimming wings between 2.0- 4.0 mm. Description: There is no shell. The animal has wings that are disc-shaped and transparent. The body is large and situated centrally between the lateral wings. These can unite to form a plate with on each side long, ciliated tentacles trailing behind. Most of the time, Desmopterus papilio hangs motionless, but flaps away in a loop pattern when disturbed. There are reddish-brown spots at the margin of the wings.

Further reading

• Sakthivel M. (1972). "Studies on Desmopterus Chun, 1889 species in the Indian Ocean". 'Meteor' Forschungsergebnisse (D)10: 46-57, 8 figs.