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Temporal range: Cretaceous–Recent
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Heterobranchia
Superorder: Eupulmonata
Order: Stylommatophora
A. Schmidt, 1855
about 20,500 species
Cornu aspersum (common garden snail)

Stylommatophora is an

gastropod molluscs. This taxon includes most land snails and slugs. Stylommatophorans lack an operculum, but some close their shell apertures with temporary "operculum" (epiphragm) made of calcified mucus. They have two pairs of retractile tentacles, the upper pair of which bears eyes on the tentacle tips. All stylommatophorans are hermaphrodites

The two strong synapomorphies of Stylommatophora are a long pedal gland placed beneath a membrane and two pairs of retractile tentacles.[4]

Stylommatophora are known from the Cretaceous period up to the present day.[5] A molecular clock estimate puts the origin of the crown group also to the Cretaceous.[6]

2017 taxonomy

The most up-to-date formal classification of Stylommatophora is that of Bouchet et al. (2017).[3] Continuously updated information may be found at MolluscaBase.[7] The 2017 system already becomes obsolete in some parts due to new phylogenetic studies.

Rhytidoidea is apparently not a monophyletic group, but rather a collection of lineages from the southern hemisphere with unresolved relationships.[8]

suborder Achatinina [“Achatinoid Clade”]

suborder Scolodontina

suborder Helicina [“Non-Achatinoid Clade”]

2005 taxonomy

According to the taxonomy of the Gastropoda by Bouchet & Rocroi (2005) based on evolutionary ancestry, Stylommatophora is a clade in the clade Eupulmonata within informal group Pulmonata.[9] It uses unranked clades for taxa above the rank of superfamily (replacing the ranks suborder, order, superorder and subclass) and the traditional Linnaean approach for all taxa below the rank of superfamily.



clade Elasmognatha

clade Orthurethra

  • Superfamily
  • Superfamily
  • Superfamily
  • Superfamily Pupilloidea
  • Superfamily

informal group Sigmurethra


limacoid clade
" (within the Sigmurethra)

(not in limacoid clade, but is within the Sigmurethra)

Cepaea hortensis, within the Helicoidea.
An individual of Trochulus hispidus, a stylommatophoran land snail in the family Hygromiidae within the Helicoidea

Previous taxonomy[citation needed]


  1. ^ Solem A. (1978). Classification of the land Mollusca. In: Fretter V. & Peake J. (eds). Pulmonates, Vol. 2A. London, Academic Press, 49–97.
  2. .
  3. ^ a b c Philippe Bouchet, Jean-Pierre Rocroi, Bernhard Hausdorf, Andrzej Kaim, Yasunori Kano, Alexander Nützel, Pavel Parkhaev, Michael Schrödl and Ellen E. Strong. 2017. Revised Classification, Nomenclator and Typification of Gastropod and Monoplacophoran Families. Malacologia, 61(1-2): 1-526.
  4. .
  5. .
  6. .
  7. ^ "Molluscabase". Retrieved 2023-08-23.
  8. ^
    PMID 37494326
  9. ^ Bouchet, Philippe; Rocroi, Jean-Pierre; Frýda, Jiří; Hausdorf, Bernhard; Ponder, Winston; Waldés, Ángel; Warén, Anders (2005). "Classification and Nomenclator of Gastropod Families". Malacologia. 47: 1–397.