|Various examples of Caenogastropoda|
Caenogastropoda is a taxonomic subclass of molluscs in the class Gastropoda. It is a large diverse group which are mostly sea snails and other marine gastropod mollusks, but also includes some freshwater snails and some land snails. The subclass is the most diverse and ecologically successful of the gastropods. 
Caenogastropoda contains many families of shelled marine molluscs – including the periwinkles, cowries, wentletraps, moon snails, murexes, cone snails and turrids – and constitutes about 60% of all living gastropods.
The Caenogastropoda exhibit torsion, and thus are included in what was previously called the Streptoneura (meaning twisted nerves), also known as Prosobranchia (meaning gills forward). Specifically, they are characterized by having only a single auricle in the heart and a single pair of gill leaflets, and are equivalent to the Monotocardia or Pectinobranchia of older authors.
The taxon Caenogastropoda was first established by Leslie Reginald Cox in 1960 as a superorder but now sometimes it is retained as a clade. Based on optimal phylogenetic analysis, it is deemed monophyletic. This Caenogastropoda combines the older taxa Mesogastropoda and Stenoglossa from the classification by Johannes Thiele and is equivalent to the revised Monotocardia as defined by Mörch in 1865.
Caenogastropoda can be divided into two major groups, based on the anatomy of the radula:
- Taenioglossa (from taenio meaning band), equivalent to the older Mesogastropoda, with typically seven teeth in each radular row.
- Stenoglossa (from steno meaning narrow), the Neogastropoda, with only 1–3 teeth per row.
Ponder & Lindberg, 1997 and others since (e.g. Vega et al., 2006; Harzhauser, 2004; and Pina, 2002.) show Caenogastropoda as a superorder, following the sense of Cox, 1960. More recently Bouchet & Rocroi, 2005 revised Caenogastropoda as a clade.
- Caenogastropoda of uncertain systematic position
- an informal group Architaenioglossa
- clade Sorbeoconcha
- clade Hypsogastropoda
Latest views by the World Register of Marine Species
Sorbeoconcha should include [Cerithioidea + Campaniloidea + all Hypsogastropoda (i.e. the remaining Caenogastropoda)], see definition in Ponder & Lindberg, 1997: 225, not only [Cerithioidea + Campaniloidea] as suggested by the indent pattern in Bouchet & Rocroi. Neotaenioglossa Haller, 1892 suggested in Ruud Bank’s draft for Fauna Europaea is not retained because it would need severe emendation to remove Pyramidellids, Cerithioids, etc. included in its original definition, and therefore would be too far from Haller's concept if it were to fit the concept of Sorbeoconcha. Although cladistically sound, the taxon Sorbeoconcha is skipped in the classification scheme because (1) ten years after its publication, the name still sounds unfamiliar to most and (2) it is not very helpful in the classification because it includes the bulk of Caenogastropoda (only keeping out small stem groups Abyssochrysidae, Provannidae, and the architaenioglossate taxa). This is not final, opinions are welcome.
- Taxonomy as provided by WoRMS in 2021 
- Subterclass Sorbeoconcha
- Superorder Hypsogastropoda
- Order Architaenioglossa
- Order Littorinimorpha
- Order Neogastropoda
- Order [unassigned] Caenogastropoda (temporary name)
- Order Stenoglossa has become a synonym of Neogastropoda
- Ponder, W. F.; Colgan, D. J.; Healy, J.; Nützel, A.; Simone, L. R. L.; Strong, E. E. (2008). "Caenogastropoda". In Ponder, W. F.; Lindberg, D. L. (eds.). Phylogeny and Evolution of the Mollusca. Berkeley: U. California Press. pp. 331–383. hdl:10088/7547.
- Cox L. R. (1960). In: Moore R. C. (ed.) Treatise on invertebrate paleontology. Part I., Mollusca 1, Gastropoda. The Geological Society of America, University of Kansas Press, Lawrence. xxiii + 351 pp., page 311.
- "Digital Atlas of Ancient Life".
- Hayes, Kenneth A.; Cowie, Robert H.; Thiengo, Silvana C. (2009). "A global phylogeny of apple snails: Gondwanan origin, generic relationships, and the influence of outgroup choice (Caenogastropoda: Ampullariidae)". Biological Journal of the Linnean Society. 98: 61–76. doi:10.1111/j.1095-8312.2009.01246.x..
- Caenogastropoda, Paleobiology
- Aktipis, Stephanie W.; Giribet, Gonzalo (2010). "A phylogeny of Vetigastropoda and other "archaeogastropods": Re-organizing old gastropod clades". Invertebrate Biology. 129 (3): 220–240. doi:10.1111/j.1744-7410.2010.00198.x.
- Bouchet, Philippe; Rocroi, Jean-Pierre; Frýda, Jiri; Hausdorf, Bernard; Ponder, Winston; Valdés, Ángel & Warén, Anders (2005). "Classification and nomenclator of gastropod families". Malacologia. Hackenheim, Germany: ConchBooks. 47 (1–2): 1–397. ISBN 3-925919-72-4. ISSN 0076-2997.
- F. J. Vega et al. 2006. El Espinal, a new plattenkalk facies locality from the Lower Cretaceous Sierra Madre Formation, Chiapas, southeastern Mexico. Revista Mexicana de Ciencias Geológicas 23(3):323-333
- Harzhauser M. (2004). "Oligocene gastropod faunas for the Eastern Mediterranean (Mesohellenic Trough/Greece and Esfahan-Sirjan Basin/Central Iran)". Courier Forschungsinstitut Senckenberg 248: 93-181.
- A.Pina -Caenogastropoda
- Colgan, D.J.; Ponder, W.F.; Beacham, E.; MacAranas, J. (2007). "Molecular phylogenetics of Caenogastropoda (Gastropoda: Mollusca)" (PDF). Molecular Phylogenetics and Evolution. 42 (3): 717–737. doi:10.1016/j.ympev.2006.10.009. PMID 17127080.
- Gofas, S. (2013). Sorbeoconcha. Accessed through: World Register of Marine Species on 2013-06-28
- WoRMS (2021). Caenogastropoda. Accessed at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=224570 on 2021-07-26