A conch
is a common name

Common name

A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...

 which is applied to a number of different species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of medium-sized to large sea snail

Snail

Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...

s or their shells

Gastropod shell

The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...

, generally those which are large and have a high spire

Spire (mollusc)

A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...

 and a siphonal canal

Siphonal canal

Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is drawn into the mantle cavity and over the gill and which serves as a chemoreceptor to locate food. In many carnivorous snails, where the siphon is particularly long, the structure...

.

True conches are marine

Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 gastropod molluscs in the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Strombidae

Strombidae

Strombidae, commonly known as the true conchs, is a taxonomic family of medium-sized to very large sea snails, marine gastropod mollusks in the superfamily Stromboidea....

, specifically in the genus Strombus

Strombus

Strombus, common name the true conchs, is a genus of medium to large sea snails with an operculum, marine gastropod mollusks in the family Strombidae, the true conchs and their immediate relatives....

and other closely related genera such as Eustrombus

Eustrombus

Lobatus is a genus of very large sea snails, marine gastropod mollusks in the family Strombidae, the true conchs. :Some of the species within this genus were previously placed in the genus Eustrombus.-Species:...

.

There are also many species often called "conch" that are not in the family Strombidae, and these include Melongena

Melongena

Melongena is a genus of sea snails, marine gastropod mollusks in the family Melongenidae, the crown conches and their allies.-Species:Species within the genus Melongena include:* Melongena bicolor...

species (family Melongenidae

Melongenidae

Melongenidae, the crown conchs, busycon whelks and their relatives, are a taxonomic family of large to very large marine gastropods in the clade Neogastropoda.- Taxonomy :Genera Busycon and Busycotypus were placed in Melongenidae...

), and the horse conch Pleuroploca gigantea

Pleuroploca gigantea

Pleuroploca gigantea, common name the Florida horse conch, is a species of extremely large predatory subtropical and tropical sea snail, a marine gastropod mollusk in the family Fasciolariidae, the spindle snails, tulip snails and their allies....

(family Fasciolariidae

Fasciolariidae

Fasciolariidae, common name the "tulip snails and spindle snails", is a family of small to large sea snails, marine gastropod mollusks in the superfamily Buccinoidea....

).