Neritimorpha is a taxonomic grouping, an unranked major

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English ter ...

of snails,

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusks Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

. This grouping includes land snails,

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the a ...

s, slugs, some deepwater

limpet Limpets are a group of aquatic snails that exhibit a conical gastropod shell, shell shape (patelliform) and a strong, muscular foot. Limpets are members of the class Gastropoda, but are polyphyletic, meaning the various groups called "limpets" ...

s, and also

freshwater snail Freshwater snails are gastropod mollusks which live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs ...

s. Neritimorpha contains around 2,000 extant species. Some Neritimorphs are commonly kept as pets. This clade used to be known as the superorder Neritopsina. The clade Neritimorpha is, based on optimal phylogenetic analysis, deemed

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gr ...

Etymology

The clade’s name, Neritimorpha, is from the Ancient Greek νηρίτης (nērī́tēs 'Nerite') and μορφή (morphḗ 'form').

Geologic History and Evolution

Neritimorpha has an extremely rich geologic history, going back to early

Ordovician The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. T ...

. This clade has been considered to be a leftover of early gastropod diversification.

1997 taxonomy

According to the taxonomy of the Gastropoda (Ponder & Lindberg, 1997) Neritopsina is a

superorder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

in the subclass

Orthogastropoda 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 (Ponder & Lindberg, 1997). This taxon is no longer used according ...

. The superfamily

Palaeotrochoidea Palaeotrochidae is an extinct family of fossil snails, gastropod mollusks in the clade Neritimorpha according to the taxonomy of the Gastropoda (Bouchet & Rocroi, 2005). This is the only family in the superfamily Palaeotrochoidea. This family ha ...

is contained within Neritopsina but its order placement is undetermined.

2005 taxonomy

The taxonomy of the Gastropoda by Bouchet & Rocroi, 2005Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdes A. & Warén A. 2005. ''Classification and nomenclator of gastropod families''. Malacologia: International Journal of Malacology, 47(1-2). ConchBooks: Hackenheim, Germany. . ISSN 0076-2997. 397 pp. http://www.vliz.be/Vmdcdata/imis2/ref.php?refid=78278 categorizes Neritimorpha as a

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

. It is one of the 6 highest clades in Gastropoda. It contains the clades

Cyrtoneritimorpha Cyrtoneritimorpha, also Cyrtoneritida, is a clade of fossil sea snails, marine gastropod mollusks within the clade Neritimorpha Neritimorpha is a taxonomic grouping, an unranked major clade of snails, gastropod mollusks. This grouping inc ...

Cycloneritimorpha Cycloneritida (nerites and false-limpets) is an order of land snails, freshwater snails, and sea snails.MolluscaBase eds. (2020). MolluscaBase. Cycloneritida. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aph ...

, as well as

Paleozoic The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ...

Neritimorpha of uncertain position. Clades (and uncertain position taxa) in Neritimorpha include: * †

Neritimorpha of uncertain position * † clade

* clade

Four extant superfamilies are recognised:

Helicinoidea Helicinoidea is a taxonomic superfamily of land snails that have an operculum. In other words, they are terrestrial operculate gastropod mollusks. They are in the superfamily Neritoidea and are quite closely related to the marine and freshwater ...

, Hydrocenoidea, Neritoidea and Neritopsoidea.

References

{{Taxonbar, from=Q18713253 Protostome unranked clades

Etymology

Geologic History and Evolution

1997 taxonomy

2005 taxonomy

See also

References