Sigmurethra is a
taxonomic category of air-breathing
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 kn ...
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 sm ...
s,
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
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. ...
molluscs
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is es ...
. This is an informal group which includes most land snails 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 sm ...
s.
The two strong synapomorphies of Sigmurethra are a long pedal gland placed beneath a membrane and retractile tentacles.
Several families in this group contain species of snails and slugs that create
love dart
A love dart (also known as a gypsobelum, shooting darts, or just as darts) is a sharp, calcareous or chitinous dart which some hermaphroditic land snails and slugs create. Love darts are both formed and stored internally in a dart sac. These ...
s.
Sigmurethra are known from the
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...
to the
Recent periods.
Taxonomy
2005 Taxonomy
In the
taxonomy of the Gastropoda by Bouchet & Rocroi, 2005, Sigmurethra is an "Informal Group", a subsection of the
Stylommatophora.
[Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdés Á. & Warén A. 2005. ''Classification and nomenclator of gastropod families''. Malacologia: International Journal of Malacology, 47(1-2). ConchBooks: Hackenheim, Germany. . . 397 pp. http://www.vliz.be/Vmdcdata/imis2/ref.php?refid=78278]
It consists of the following families:
*Superfamily
Clausilioidea
**Family
Clausiliidae
** † Family
Anadromidae
** † Family
Filholiidae
** † Family
Palaeostoidae
*Superfamily
Orthalicoidea
**Family
Orthalicidae
**Family
Cerionidae
**Family
Coelociontidae
** † Family
Grangerellidae
**Family
Megaspiridae
**Family
Placostylidae
**Family
Urocoptidae
*Superfamily
Achatinoidea
**Family
Achatinidae
**Family
Ferussaciidae
**Family
Micractaeonidae
**Family
Subulinidae
*Superfamily
Aillyoidea
**Family
Aillyidae
*Superfamily
Testacelloidea
**Family
Testacellidae
**Family
Oleacinidae
**Family
Spiraxidae
*Superfamily
Papillodermatoidea
**Family
Papillodermatidae
*Superfamily
Streptaxoidea
**Family
Streptaxidae
*Superfamily
Rhytidoidea
**Family
Rhytididae
**Family
Chlamydephoridae
**Family
Haplotrematidae
**Family
Scolodontidae
*Superfamily
Acavoidea
**Family
Acavidae
**Family
Caryodidae
**Family
Dorcasiidae
**Family
Macrocyclidae
**Family
Megomphicidae
**Family
Strophocheilidae
*Superfamily
Plectopyloidea
**Family
Plectopylidae
**Family
Corillidae
**Family
Sculptariidae
*Superfamily
Punctoidea
**Family
Punctidae
** † Family
Anastomopsidae
**Family
Charopidae
**Family
Cystopeltidae
**Family
Discidae
**Family
Endodontidae
Endodontidae is a taxonomic family of very small air-breathing land snails and slugs, terrestrial pulmonate gastropod mollusks in the superfamily Punctoidea.
This family, which includes both snails and slugs, appears to have once been much mo ...
**Family
Helicodiscidae
**Family
Oreohelicidae
**Family
Thyrophorellidae
*Superfamily
Sagdoidea
**Family
Sagdidae
Sagdidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks with highest diversity in the Greater Antilles. It has been classified in its own superfamily Sagdoidea and as a member of the superfamily Helicoidea ...
limacoid clade
*Superfamily
Staffordioidea
**Family
Staffordiidae
*Superfamily
Dyakioidea
**Family
Dyakiidae
*Superfamily
Gastrodontoidea
**Family
Gastrodontidae
**Family
Chronidae
**Family
Euconulidae
**Family
Oxychilidae
**Family
Pristilomatidae
**Family
Trochomorphidae
**Fossil taxa probably belonging to the
Gastrodontoidea
***Subfamily †
Archaeozonitinae
***Subfamily †
Grandipatulinae
***Subfamily †
Palaeoxestininae
*Superfamily
Parmacelloidea
**Family
Parmacellidae
**Family
Milacidae
**Family
Trigonochlamydidae
*Superfamily
Zonitoidea
**Family
Zonitidae
*Superfamily
Helicarionoidea
**Family
Helicarionidae
**Family
Ariophantidae
**Family
Urocyclidae
*Superfamily
Limacoidea
**Family
Limacidae
**Family
Agriolimacidae
**Family
Boettgerillidae
**Family
Vitrinidae
Informal group Sigmurethra continued
Two superfamilies belongs to clade Sigmurethra, but they are not in the limacoid clade.
*Superfamily
Arionoidea
Arionoidea is a taxonomic group, superfamily of air-breathing land slugs, shell-less terrestrial pulmonate gastropod mollusks.
Families
Families within the superfamily Arionoidea include:
* Arionidae
* Anadenidae
* Ariolimacidae
* Binneyi ...
**Family
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 slu ...
**Family
Anadenidae
**Family
Ariolimacidae
Ariolimacidae 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 (). ...
**Family
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 gastropod ...
**Family
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 ...
**Family
Philomycidae
*Superfamily
Helicoidea
Helicoidea is a taxonomic superfamily of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the clade Stylommatophora.
Taxonomy 2005 taxonomy
There are 19 families within the superfamily Helicoidea according to the taxonom ...
**Family
Helicidae
**Family
Bradybaenidae
**Family
Camaenidae
**Family
Cepolidae
**Family
Cochlicellidae
**Family
Elonidae
**Family
Epiphragmophoridae
**Family
Halolimnohelicidae
**Family
Helicodontidae
**Family
Helminthoglyptidae
**Family
Humboldtianidae
**Family
Hygromiidae
Hygromiidae is a taxonomic family of small to medium-sized air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Helicoidea. Helicellidae Ihering, 1909
Anatomy
Some snails in genera within this family create a ...
**Family
Monadeniidae
**Family
Pleurodontidae
**Family
Polygyridae
**Family
Sphincterochilidae
**Family
Thysanophoridae
**Family
Trissexodontidae
**Family
Xanthonychidae
(Families that are exclusively fossil are indicated with a dagger †)
New families after 2005
*Superfamily
Streptaxoidea
**
Diapheridae - In 2010, Sutcharit et al. (2010)
[Sutcharit C., Naggs F., Wade C. M., Fontanilla I. & Panha S. (2010). "The new family Diapheridae, a new species of ''Diaphera'' Albers from Thailand, and the position of the Diapheridae within a molecular phylogeny of the Streptaxoidea (Pulmonata: Stylommatophora)". '' Zoological Journal of the Linnean Society'' 160: 1-16. .] established a new family Diapheridae within the Streptaxoidea.
2017 Taxonomy
After excluding groups not related, the informal group Sigmurethra becomes suborder
Helicina
''Helicina'' is a genus of tropical and subtropical land snails with an operculum, terrestrial gastropod mollusks.
This is the type genus of its family ( Helicinidae) and subfamily ( Helicinae), as well as the superfamily Helicinoidea. This ra ...
, with the following nine infraorders and a collection of families with no superfamily:
*Suborder
Helicina
''Helicina'' is a genus of tropical and subtropical land snails with an operculum, terrestrial gastropod mollusks.
This is the type genus of its family ( Helicinidae) and subfamily ( Helicinae), as well as the superfamily Helicinoidea. This ra ...
("Non-Achatinoid Clade")
**Infraorder
Arionoidei
**Infraorder
Clausilioidei
**Infraorder
Helicoidei: formed from
Helicoidea
Helicoidea is a taxonomic superfamily of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the clade Stylommatophora.
Taxonomy 2005 taxonomy
There are 19 families within the superfamily Helicoidea according to the taxonom ...
and
Sagdoidea
**Infraorder
Limacoidei: formed from original ''
limacoid clade''
**Infraorder
Oleacinoidei
***
Oleacinoidea: formed from original
Testacelloidea but with the family
Testacellidae excluded;
***
Haplotrematoidea: formed from original
Rhytidoidea and
Haplotrematidae
**Infraorder
Orthalicoidei
**Infraorder
Pupilloidei
The Pupilloideiis an taxonomic infraorder of air-breathing land snails, semislugs and slugs, terrestrial pulmonate gastropod molluscs
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of wh ...
(
Orthurethra)
**Infraorder
Rhytidoidei: formed by
Rhytidoidea merging with contents from
Acavoidea.
**Infraorder
Succineoidei (
Elasmognatha)
References
{{taxonbar, from=Q3483567
Stylommatophora
Extant Cretaceous first appearances
Gastropod taxonomy