Basommatophora

Basommatophora Temporal range: Carboniferous–recent PreꞒ Ꞓ O S D C P T J K Pg N
The larger of the two snails shown here is Lymnaea stagnalis; the smaller one is Physella acuta, family Physidae
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
Informal group:	Pulmonata
Informal group:	Basommatophora Keferstein in Bronn, 1864
Families
See text
Diversity[1]
about 300 species

Basommatophora was a term that was previously used as a

Basommatophora are known from the Carboniferous to the Recent periods.^[2]

Most of the families in this suborder are air-breathing freshwater snails. The three most abundant families in terms of number of species are, the Lymnaeidae (pond snails), the Planorbidae (ramshorn snails) and the Physidae (pouch or bubble snails). These are found in ponds, creeks, ditches, and shallow lakes nearly worldwide.

The

Basommatophorans are characterized by having their eyes located at the base of their non-retractile tentacles, rather than at the tips, as in the true land snails Stylommatophora. The majority of basommatophorans have shells that are thin, translucent, and relatively colorless, and all except Amphibola lack an operculum.

In the older taxonomy of the Gastropoda (Ponder & Lindberg, 1997) the suborder Basommatophora consisted of the families :

• Acroloxidae Thiele, 1931
• Amphibolidae J. E. Gray, 1840 - only one species Amphibola crenata
• Ancylidae
• Carychiidae
  Jeffreys, 1830
• Chilinidae
• Lancidae
• Latiidae
• Lymnaeidae Rafinesque, 1815
• Otinidae
  H. Adams & A. Adams, 1855
• Physidae Fitzinger, 1833
• Planorbidae Rafinesque, 1815
• Siphonariidae J. E. Gray, 1840
• Trimusculidae
  Zilch, 1959

The informal group Basommatophora contains the following superfamilies and the

• Superfamily Amphiboloidea Gray, 1840
  • Family Amphibolidae Gray, 1840
• Superfamily Siphonarioidea Gray, 1827
  • Family Siphonariidae Gray, 1827
  • † Family Acroreiidae Cossmann, 1893

Clade

Hygrophila

• Superfamily Chilinoidea Dall, 1870
  • Family
    Chilinidae
    Dall, 1870
  • Family
    Latiidae
    Hutton, 1882
• Superfamily
  Acroloxoidea
  Thiele, 1931
  • Family Acroloxidae Thiele, 1931
• Superfamily Lymnaeoidea Rafinesque, 1815
  • Family Lymnaeidae Rafinesque, 1815
• Superfamily
  Planorboidea
  Rafinesque, 1815
  • Family Planorbidae Rafinesque, 1815
  • Family Physidae Fitzinger, 1833

The family

The family