Onchidiidae | |
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A live but partially retracted individual of Onchidella sp. | |
A live and active individual of Onchidella nigricans | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Gastropoda |
(unranked): |
clade Heterobranchia clade Euthyneura |
Superfamily: |
Onchidioidea Rafinesque, 1815 |
Family: |
Onchidiidae Rafinesque, 1815 |
Genera | |
See text |
|
Synonyms | |
|
clade Euthyneura
clade Panpulmonata
clade Eupulmonata
clade Systellommatophora
See text
Onchidiidae are a family of small, air-breathing sea (and land) slugs. They are shell-less marine (except of 5 species)pulmonate gastropod molluscs. Onchidiidae is the only family within the superfamily Onchidioidea.
These animals are quite unusual in that they are emphatically not opisthobranchs with gills, as are almost all of the sea slugs. Instead these creatures are pulmonates. They are more closely related to air-breathing land and freshwater snails and slugs than they are to most other sea snails and sea slugs.
This family has no subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).
There are 143 species names within the Onchidiidae, but a detailed revision has not been made yet, because there is no living malacologist expert enough on the whole group to properly identify them.
Adult onchidiids lack a shell, although a shell and operculum is present at the larval stage. The mantle cavity is reduced to the point of absence, correlating with a loss of gills, raphes, and other characters usually found in the mantle cavity. The organism is completely detorted.
Slugs in this family make and use love darts made of chitin.