The caudal mucous pit, or caudal mucous horn, is an anatomical structure on the tail end of the foot of various

land snail A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial gastropod mollusks that have shells (those without shells are known as ...

s and

slug Slug, or land slug, is a common name for any apparently shell-less terrestrial gastropod mollusc. The word ''slug'' is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced shell, or only a smal ...

s, terrestrial

pulmonate Pulmonata or pulmonates, is an informal group (previously an order, and before that a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includ ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusks. The function of this pit is the resorption of mucus when the

is moving (see also Muratov 1999). An incorrect and yet often-used term for this structure is the "caudal gland".Barker G. M. (2001) "Gastropods on Land: Phylogeny, Diversity and Adaptive Morphology." in Barker G. M. (ed.):
The biology of terrestrial molluscs
. CABI Publishing, Oxon, UK, . 1-146, cited pages: page 90 and pages 140-143. This area also used to be referred to by the term "caudal pore".

Families

Families of snails and slug where a caudal mucous pit exists in every species included: *

Arionidae Arionidae, common name the "roundback slugs" or "round back slugs" are a taxonomic family of air-breathing land slugs, terrestrial pulmonate gastropod mollusks in the superfamily Arionoidea. Distribution The distribution of this family of slug ...

: * Endodontidae * Polygyridae *

Helicodiscidae Helicodiscidae is a family of small air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Punctoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Genera Genera within the family i ...

* Daudebardiinae (a subfamily of

Oxychilidae Oxychilidae is a taxonomic family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Gastrodontoidea. Distribution The distribution of Oxychilidae includes the Nearctic, western-Palearctic, eastern-Palear ...

) *

Urocyclidae Urocyclidae is a family of air-breathing land snails, semi-slugs and land slugs, terrestrial pulmonate gastropod mollusks in the superfamily Helicarionoidea, (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Some spec ...

* Helicarionidae * Ariophantidae * Systrophiidae (Systrophiidae is a synonym for Scolodontinae, the subfamily of family

Scolodontidae Scolodontidae is a taxonomic family of air-breathing land snails, terrestrial pulmonate gastropod mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or ...

) *

Dyakiidae Dyakiidae is a family of air-breathing land snails terrestrial pulmonate gastropod mollusks in the superfamily Trochomorphoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Some of the species in this family are sin ...

Families/subfamilies where is caudal mucous pit exists only on some species included: * Ariopeltinae (a subfamily of

Oopeltidae Oopeltidae is a family of air-breathing land slugs, terrestrial pulmonate gastropod mollusks in the superfamily Arionoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Subfamilies and genera The family Oopeltidae c ...

) * Charopidae *

Binneyidae Binneyidae is a family of air-breathing land slugs, terrestrial pulmonate gastropod mollusks in the superfamily Arionoidea Arionoidea is a taxonomic group, superfamily of air-breathing land slugs, shell-less terrestrial pulmonate gastr ...

* Ariolimacinae (a subfamily of

Ariolimacidae Ariolimacidae is a family of air-breathing land slugs, terrestrial pulmonate gastropod mollusks in the superfamily Arionoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Subfamilies and genera The family Ariolimac ...

) *

Anadenidae Anadenidae is a family of air-breathing land slugs, terrestrial pulmonate gastropod mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). A ...

Trochomorphidae Trochomorphidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Gastrodontoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). Since 2017, its classification has bee ...

* Helminthoglyptidae *

Ferussaciidae Ferussaciidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Achatinoidea. MolluscaBase eds. (2020). MolluscaBase. Ferussaciidae Bourguignat, 1883. Accessed through: World Register of Marine ...

* Subulinidae * Euconulidae *

Zonitidae Zonitidae, common name the true glass snails, are a family of mostly rather small, air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Zonitoidea. Zonitidae is the only family in the superfamily Zonitoidea. Th ...

* Vitreinae (Vitreinae is a synonym for

Pristilomatidae Pristilomatidae is a taxonomic family of air-breathing land snails, terrestrial gastropod mollusks in the superfamily Gastrodontoidea. According to the 2005 taxonomy of the Gastropoda by Bouchet & Rocroi these snails belong to the "limacoid ...

) *

Gastrodontidae Gastrodontidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Gastrodontoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005). MolluscaBase eds. (2020). MolluscaBase ...

References

External links

Photo of caudal mucous pit of ''Arion subfuscus''
{{Gastropod anatomy Gastropod anatomy

Families

References

Further reading

External links