The Systellommatophora (synonym Gymnomorpha) is a clade of primitive, air-breathing slugs, according to the

taxonomy of the Gastropoda (Bouchet & Rocroi, 2005) The taxonomy of the Gastropoda as it was revised in 2005 by Philippe Bouchet and Jean-Pierre Rocroi is a system for the scientific classification of gastropod mollusks. (Gastropods are a taxonomic class of animals which consists of snails and s ...

. They are marine and

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

pulmonate gastropods within the

Heterobranchia Heterobranchia, the ''heterobranchs'' (meaning "different-gilled snails"), is a taxonomic clade of snails and slugs, which includes marine, aquatic and terrestrial gastropod mollusks. Heterobranchia is one of the main clades of gastropods. Cur ...

. There are two superfamilies in this clade. Slugs in the superfamily Onchidioidea are primarily marine (except for five land-dwelling or freshwater species), whereas slugs in the superfamily Veronicelloidea are primarily terrestrial.

Anatomy

No species in this clade have shells as adults. These slugs are distinguished by the location of the anus at the rear of the body. Although neither superfamily bears shells as adults, the Onchidioidea do possess a vestigial, non-mineralized shell sac and possess a larval shell. It is not known whether or not the veronicellids bear a larval shell.

Taxonomy

According to the previous

taxonomy of the Gastropoda (Ponder & Lindberg, 1997) The taxonomy of the Gastropoda, as revised by Winston Ponder and David R. Lindberg in 1997, is an older taxonomy of the class Gastropoda, the class of molluscs consisting of all snails and slugs. The full name of the work in which this taxonom ...

Systellommatophora was considered to be a suborder or an order. The following two superfamilies and families have been recognized in the taxonomy of Bouchet & Rocroi (2005): * superfamily Onchidioidea

Rafinesque Constantine Samuel Rafinesque-Schmaltz (; October 22, 1783September 18, 1840) was a French 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ultimat ...

, 1815 ** Onchidiidae

, 1815 * Superfamily Veronicelloidea Gray, 1840 **

Veronicellidae The Veronicellidae, also known by their common name the leatherleaf slugs, are a family of pulmonate terrestrial slugs. The herbivorous molluscs occur mainly in the tropical and subtropical areas of America, Asia and Africa. They act as intermed ...

Gray, 1840 ** Rathouisiidae Heude, 1885

References

{{Taxonbar, from=Q1319200 Panpulmonata