Archaeogastropoda

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Archaeogastropoda
Temporal range: Late Cambrian–Recent
Turbo.jpg
shells of Turbo spp.
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Order: "Archaeogastropoda"
Thiele, 1925
Families

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Archaeogastropoda (also known as Aspidobranchia [1] ) was a taxonomic order of sea snails used in older classifications of gastropods, i.e. snails and slugs. Archeogastropoda are marine prosobranch gastropod mollusks, mainly herbivores, typically having two gills and a double-chambered heart, with the eggs and sperm discharged directly into the water. They were traditionally regarded as a relatively primitive group.

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This older classification of the gastropods is based on the classification of Johannes Thiele (1925). This classification was not based on true phylogenetic relationships, but on more general affinities between the groups. In the last few years, two new cladistic taxonomies of the gastropods have been published (in 1997 and 2005). This has led to an extensive reclassification of gastropod taxa. The taxon Archaeogastropoda was found to be a paraphyletic group, and therefore unacceptable in a strictly cladistic classification.

In the 1997 classification, most of the former Archaeogastropoda were included in:

A more detailed classification can be found on Gastropoda.

Older system of classification

See also

Related Research Articles

Gastropoda Class of molluscs

The gastropods, commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda.

Mesogastropoda Historic group of snails

Mesogastropoda was for many years a traditional taxonomic group of snails, an order. The order was composed mostly of sea snails, but it also included some land snails and freshwater snails, all of which were prosobranch gastropod mollusks.

Prosobranchia Historic group of molluscs

Prosobranchia was a large taxonomic subclass of sea snails, land snails and freshwater snails. This taxon of gastropods dates back to the 1920s. It has however been proven to be polyphyletic. Generally speaking in biology taxonomy is required to reflect phylogeny, in other words the classification of a group must reflect its evolutionary descent, as far as that is known, so the taxon Prosobranchia is no longer considered suitable to be used.

Orthogastropoda was a major taxonomic grouping of snails and slugs, an extremely large subclass within the huge class Gastropoda according to the older taxonomy of the Gastropoda.

Caenogastropoda Clade of sea snails

Caenogastropoda is a taxonomic clade, 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 clade is the most diverse and ecologically successful of the gastropods.

The Bellerophontida is a taxonomic order of extinct marine mollusks that are found in the fossil record from the Lower Cambrian to the Lower Triassic. They are considered by some experts to be primitive sea snails with primarily symmetrically coiled shells, marine gastropod mollusks.

Stylommatophora Order of gastropods

Stylommatophora is an order of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This taxon includes most land snails and slugs.

Neritopsoidea Superfamily of gastropods

Neritopsoidea is a taxonomic grouping, a superfamily of sea snails, marine gastropod mollusks in the clade Cycloneritimorpha, within the clade Neritimorpha,, or in the order Neritoina within superorder Cycloneritimorpha within the subclass Neritimorpha,.

The taxonomy of the Gastropoda as it was revised in 2005 by Philippe Bouchet and Jean-Pierre Rocroi is a system for the scientific classification of gastropod mollusks. The paper setting out this taxonomy was published in the journal Malacologia. The system encompasses both living and extinct groups, as well as some fossils whose classification as gastropods is uncertain.

The taxonomy of the Gastropoda, as revised by Winston Ponder and David R. Lindberg in 1997, is an older taxonomy of the class Gastropoda, the class of molluscs consisting of all snails and slugs. The full name of the work in which this taxonomy was published is Towards a phylogeny of gastropod molluscs: an analysis using morphological characters.

Apogastropoda Group of molluscs

Apogastropoda was previously used as a major taxonomic grouping of sea snails, marine gastropod molluscs. This infraclass mostly consisted of marine limpets and operculate snails. At least 20,000 species were considered to exist within the two clades that were included, Heterobranchia and Caenogastropoda.

Vetigastropoda Clade of sea snails

Vetigastropoda is a major taxonomic group of sea snails, marine gastropod mollusks that form a very ancient lineage. Taxonomically the Vetigastropoda are sometimes treated as an order, although they are treated as an unranked clade in Bouchet and Rocroi, 2005.

Neritimorpha Subclass of gastropods

Neritimorpha is a taxonomic grouping, an unranked clade of snails, gastropod mollusks. This grouping includes land snails, sea snails, some deepwater limpets, and also freshwater snails. This clade used to be known as the superorder Neritopsina.

Bellerophontoidea Extinct superfamily of gastropods

Bellerophontoidea, common name "bellerophonts", is a superfamily of extinct planospirally-coiled globose molluscs. This superfamily is generally included within the Gastropoda, but may instead be a group of monoplacophorans. The taxon first appeared late in the Cambrian and continued until late in the Triassic.

Cycloneritida Order of gastropods

Cycloneritida is an order of land snails, freshwater snails, and sea snails.

Pleurotomarioidea Superfamily of gastropods

Pleurotomarioidea is a superfamily of small to large marine gastropods included in the order Pleurotomariida of the subclass Vetigastropoda.

Seguenzioidea Superfamily of gastropods

Seguenzioidea is a superfamily of minute to medium-sized sea snails, marine gastropod mollusks in the clade Vetigastropoda.

Hygrophila (gastropod) Clade of molluscs

Hygrophila is a taxonomic superorder of air-breathing freshwater snails, aquatic pulmonate gastropod mollusks within the clade Panpulmonata.

This overview lists proposed changes in the taxonomy of gastropods at the family level and above since 2005, when the taxonomy of the Gastropoda by Bouchet & Rocroi (2005) was published. In other words, these are recent updates in the way various groups of snails and slugs are classified.

The biological systematics and taxonomy of invertebrates as proposed by Richard C. Brusca and Gary J. Brusca in 2003 is a system of classification of invertebrates, as a way to classify animals without backbones.

References

  1. "Answers - the Most Trusted Place for Answering Life's Questions".