Sea snail

Sea snails are 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 absence of a visible shell.

Definition

Sea snail is a common name for a diverse group of marine gastropod mollusks that typically possess a coiled shell, move using a muscular foot, and inhabit marine environments ranging from intertidal zones to the deep sea. Sea snails are not a single taxonomic group but include species from several gastropod clades, such as
Caenogastropoda, Vetigastropoda, and Heterobranchia.

Anatomy

Shell

The shells of snails are complex and grow at different speeds. The speed of growth is affected by a few variables such as the temperature of the water, depth of the water, food present for the snail, as well as isotopic oxygen levels. By looking at the composition of aragonite in the growth layers of mollusks it can be predicted the size the mollusk shell can reach.

Taxonomy

2005 taxonomy

The following cladogram is an overview of the main clades of living gastropods based on the taxonomy of Bouchet & Rocroi, with taxa that contain saltwater or brackish water species marked in boldface

Clade Patellogastropoda
Clade Vetigastropoda
Clade Cocculiniformia
Clade Neritimorpha
* Clade Cycloneritimorpha
Clade Caenogastropoda
* Informal group Architaenioglossa
* Clade Sorbeoconcha
* Clade Hypsogastropoda
** Clade Littorinimorpha
** Informal group Ptenoglossa
** Clade Neogastropoda
Clade Heterobranchia
* Informal group Lower Heterobranchia
* Informal group Opisthobranchia
** Clade Cephalaspidea
** Clade Thecosomata
** Clade Gymnosomata
** Clade Aplysiomorpha
** Group Acochlidiacea
** Clade Sacoglossa
** Group Cylindrobullida
** Clade Umbraculida
** Clade Nudipleura
*** Clade Pleurobranchomorpha
*** Clade Nudibranchia
**** Clade Euctenidiacea
**** Clade Dexiarchia
***** Clade Pseudoeuctenidiacea
***** Clade Cladobranchia
****** Clade Euarminida
****** Clade Dendronotida
****** Clade Aeolidida
* Informal group Pulmonata
** Informal group Basommatophora
** Clade Eupulmonata
*** Clade Systellommatophora
*** Clade Stylommatophora
**** Clade Elasmognatha
**** Clade Orthurethra
**** Informal group Sigmurethra
Uses

By humans

Sea snails are eaten around the world and are a food source of sterols, such as cholesterol, phytosterol, and minerals, which play an important role for human health.
Due to high calcium carbonate content, sea snail shells have potential to be used as raw material in the production of lime.