Neritidae

Neritidae
An oblique left side view of a live Theodoxus fluviatilis
Two shells of the freshwater nerite Theodoxus danubialis, scale bar in mm
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Neritimorpha clade Cycloneritimorpha
Superfamily:	Neritoidea
Family:	Neritidae Rafinesque, 1815
Diversity
About 110 freshwater species, some brackish water species, and some fully marine species

clade Cycloneritimorpha

Neritidae, common name the nerites, is a taxonomic family of small to medium-sized saltwater and freshwater snails which have a gill and a distinctive operculum, marine, brackish water and freshwater gastropod mollusks in the order Neritoida.

The family Neritidae includes marine genera such as Nerita, marine and freshwater genera such as Neritina, and freshwater and brackish water genera such as Theodoxus.

The common name "nerite" as well as the family name Neritidae and the genus name Nerita, are derived from the name of Nerites, who was a sea god in Greek mythology.

Neritidae live primarily in the southern hemisphere, but there are some exceptions, such as a genus Theodoxus or Bathynerita naticoidea.

This family consists of the five following subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005):

Genera, subgenera and species within the family Neritidae include:

Subfamily Neritinae

Subfamily † Neritariinae

Subfamily Neritininae
tribe Neritinini

tribe Theodoxini

Subfamily Smaragdiinae

Subfamily † Velatinae

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Wikipedia