Sigmurethra
Informal group of gastropods
From Wikipedia, the free encyclopedia
Sigmurethra is a taxonomic category of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This is an informal group which includes most land snails and slugs.
| Sigmurethra Temporal range: | |
|---|---|
| |
| Various examples of Sigmurethra | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| Order: | Stylommatophora |
| Informal group: | Sigmurethra |
| Superfamilies | |
| Synonyms[1] | |
| |
The two strong synapomorphies of Sigmurethra are a long pedal gland placed beneath a membrane and retractile tentacles.[2]
Several families in this group contain species of snails and slugs that create love darts.
Sigmurethra are known from the Cretaceous to the Recent periods.[3]
Taxonomy
2005 Taxonomy
In the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005, Sigmurethra is an "Informal Group", a subsection of the Stylommatophora.[4] 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 Anostomopsidae
- Family Charopidae
- Family Cystopeltidae
- Family Discidae
- Family Endodontidae
- Family Helicodiscidae
- Family Oreohelicidae
- Family Thyrophorellidae
- Superfamily Sagdoidea
- Family Sagdidae
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
- Family Arionidae
- Family Anadenidae
- Family Ariolimacidae
- Family Binneyidae
- Family Oopeltidae
- Family Philomycidae
- Superfamily Helicoidea
- Family Helicidae
- Family Bradybaenidae
- Family Camaenidae
- Family Cepolidae
- Family Cochlicellidae
- Family Elonidae
- Family Epiphragmophoridae
- Family Halolimnohelicidae
- Family Helicodontidae
- Family Helminthoglyptidae
- Family Humboldtianidae
- Family Hygromiidae
- 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)[5] established a new family Diapheridae within the Streptaxoidea.[5]
2017 Taxonomy
After excluding groups not related, the informal group Sigmurethra becomes suborder Helicina, with the following nine infraorders and a collection of families with no superfamily：[6]
- Suborder Helicina ("Non-Achatinoid Clade")
- Infraorder Arionoidei
- Infraorder Clausilioidei
- Infraorder Helicoidei: formed from Helicoidea Rafinesque, 1815 and Sagdoidea Pilsbry, 1895[7]
- Infraorder Limacoidei: formed from original limacoid clade
- Infraorder Oleacinoidei[8]
- Oleacinoidea: formed from original Testacelloidea but with the family Testacellidae excluded;
- Haplotrematoidea: formed from original Rhytidoidea and Haplotrematidae[9]
- Infraorder Orthalicoidei
- Infraorder Pupilloidei (Orthurethra)
- Infraorder Rhytidoidei: formed by Rhytidoidea merging with contents from Acavoidea.
- Infraorder Succineoidei (Elasmognatha)
