conch, common name for certain marine gastropod mollusks having a heavy, spiral shell, the whorls of which overlap each other. In conchs the characteristic gastropod foot is reduced in size and the operculum, a horny plate located on the foot and used to seal the shell opening in many gastropods, has the appearance and function of a claw. During locomotion, the operculum secures a foothold in the sand, and the conch jumps forward by means of the quick contraction of a retractor muscle called the columella muscle. Thus the conch lacks the creeping motion of most gastropods. The king conch, Strombus gigas, found in the warmer waters of the Atlantic, Caribbean, and Gulf of Mexico, has a shell 10 to 12 in. (25-30 cm) long and may weigh up to 5 lb (2.3 kg). Similar in size and distribution is the queen conch, Cassis cameo. Its shell has been used in Europe to carve cameos. Conch shells range in color from white to red; they have been used by humans to fashion a number of items, such as buttons, ornaments, or the crude trumpets made from the shell of the trumpet conch, Charonia tritonis. This conch is similar in shape to the king and queen conchs but is much more slender and reaches a length of 20 in. (50 cm). C. tritonis is found in the Gulf of Mexico and the Indian Ocean. The largest conch and also one of the largest univalves in the world is the horse conch, Pleuroploca gigantea, having a shell length of 24 in. (60 cm). It is found along the Atlantic Coast from North Carolina to Brazil. The body can retreat entirely into the shell and remain there for months if unfavorable conditions prevail. An unusual conch shell is that of the spider conch, Lambis lambis, which has leglike projections. Spider conchs are voracious carnivores, common on coral reefs. They also feed on algae, as do the king conchs. Most conchs are carnivorous, feeding on bivalve mollusks; some are scavengers as well. They inhabit tropical waters and have been used as a food source for man. The conch is classified in the phylum Mollusca, class Gastropoda, order Mesogastropoda.

Marine snail whose shell has a broadly triangular outer whorl and a wide lip, often jutting toward the uppermost point. True conchs (family Strombidae) feed on fine plant matter in warm waters. The queen conch (Strombus gigas), found from Florida to Brazil, has an ornamental shell; the pink opening into the first whorl of the shell may be 12 in. (30 cm) long. The clam-eating fulgur conchs (family Melongenidae) include the channeled conch (Busycon canaliculatum) and the lightning conch (B. contrarium), both about 7 in. (18 cm) long and common on the U.S. Atlantic coast. Seealso whelk.

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A conch (pronounced in the U.S.A. as "konk" or "konch", or /ˈkɒntʃ/) is one of a number of different species of medium-sized to large saltwater snails or their shells. True conchs are marine gastropod mollusks in the family Strombidae, and the genus Strombus.

The name "conch" however, is often quite loosely applied in English-speaking countries to several kinds of very large sea snail shells which are pointed at both ends, i.e. shells which have a high spire and a noticeable siphonal canal. These other species include the crown conch Melongena species; the horse conch Pleuroploca gigantea; and the chank shell, Turbinella species. None of these are true conchs; they are all in other taxonomic families.

The true conch species within the genus Strombus vary in size from fairly small to very large. Several of the larger species such as Strombus gigas, the pink conch or queen conch, are economically important as food sources. Strombus gigas is also capable of producing (very rarely) a pink, gem quality pearl.

At least 65 species of Strombidae are extinct, and a much larger number of species exist only in the fossil record. Of the living species, most are in the Indo-Pacific Oceans. Six species live in the greater Caribbean region, including the Queen Conch, Strombus gigas, and the West Indian Fighting Conch, Strombus pugilis.

Many species of conch, such as the Queen Conch, live on sandy bottoms among beds of sea grass in warm tropical waters.

Strombus gigas is included in Appendix II of the UNEP's CITES list of endangered species, and international trade is heavily restricted.

Anatomy

Like almost all shelled gastropods, conches have spirally constructed shells. Again, as is normally the case in many gastropods, this spiral shell growth is usually right-handed, but on very rare occasions it can be left-handed.

True conchs have long eye stalks, with colorful ring-marked eyes. The shell has a long and narrow aperture, and a short siphonal canal, with another indentation near the anterior end called a stromboid notch. This notch is where one of the two eye stalks protrudes from the shell.

The true conch has a foot ending in a pointed, sickle-shaped, operculum which can be dug into the substrate as part of an unusual "leaping" locomotion.

True conchs grow a flared lip on their shells only upon reaching sexual maturity. Animals which are harvested by fishermen before they reach this stage are juveniles, and have not had a chance to reproduce.

Conchs lay eggs in long, gelatinous strands.

Human use

As food

The "meat" of the conch is used as food, either eaten raw, as in salads, or cooked, as in fritters, chowders, gumbos, and burgers. All parts of the conch meat are edible. However, some people find only the white meat appetizing.

In East Asian cuisines, this seafood is often cut into thin slices and then steamed or stir-fried.

In El Salvador, live conch is served in a cocktail of onion, tomato, cilantro, and lemon juice. Lemon juice is squeezed onto the cocktail, causing the conch to squirm, and then the whole thing is slurped down whole, as in the manner of oysters.

Conch meat is also often confused with what in the US is known as "Scungilli", which is more accurately whelk meats.

As musical instruments

Conch shells can be used as wind instruments, by cutting a small hole in the spire and then blowing into the shell as if it were a trumpet, as in blowing horn.

Conch shell trumpets were historically used throughout the South Pacific, in countries such as Fiji. In resorts in Fiji they still blow the shell as a performance for the tourists. The Fijians also used the conch shell when the chief died: the chief's body would be brought down a special path and the conch would be played until the chief's body reached the end of the path. Only the chief's body could go down that path.

The American jazz trombonist Steve Turre also plays conches, notably with his group Sanctified Shells.

A partially echoplexed Indian conch was featured prominently as the primary instrument depicting the extraterrestrial environment of the derelict spaceship in Jerry Goldsmith's score for the film Alien. Director Ridley Scott was so impressed by the eerie effect that he requested its use throughout the rest of the score, including the Main Title.

Composer John Cage has used partially water-filled conch shells, which, when tilted slowly, create gurgling sounds beyond the player's control, which are then amplified. This sound effect was used by James Horner in the film Troy and by Annea Lockwood in her compositions.

Other uses

• Conch shells are sometimes used as decoration, as decorative planters, and in cameo making.
• In classic Mayan art, conchs are shown being utilized in many ways including as paint and ink holders for elite scribes, as bugles or trumpets, and as hand weapons (held by combatants by inserting their hands in the aperture).
• Some American Aboriginals used cylindrical conch columella beads as part of breastplates and other personal adornment. See Hair Pipes
• In some Caribbean and African American cemeteries, conch shells are placed on graves. (The Last Miles of the Way: African Homegoing Traditions, 1890-Present, edited by Elaine Nichols).
• In some Caribbean countries, cleaned Queen Conch (Strombus gigas) shells, or polished fragments, are sold, mainly to tourists, as souvenirs or in jewelry. Without a permit, however, export is a breach of CITES regulations, and may lead to arrest This is most likely to occur on return to the tourist's home country while clearing customs. In the UK conch shells are the ninth most seized import.
• Conch shells are occasionally used as a building material, either in place of bricks, or as bulk for landfill.

Religious use

The Hindu tradition

A Shankh shell (the shell of a Turbinella species in the gastropod family Turbinellidae) is often referred to in the West as a conch shell, or a chank shell. This is a major Hindu article of prayer. It is used as a trumpet, as part of religious practices, for example puja. The chank trumpet is sounded during worship at specific points, accompanied by ceremonial bells and singing.

In the story of Dhruva the divine conch plays a special part. The warriors of ancient India blew conch shells to announce battle, as is described in the beginning of the war of Kurukshetra, in the Mahabharata, the famous Hindu epic.

The god of Preservation, Vishnu, is said to hold a special conch, Panchajanya, that represents life, as it has come out of life-giving waters.

The Buddhist tradition

Buddhism has also incorporated the conch shell, as one of the Eight Auspicious Symbols.

Ancient Peru

• The Moche people of ancient Peru worshiped the sea and often depicted conch shells in their art.

In literature and in the oral tradition

William Golding's Lord of the Flies features frequent references to "the Conch". In the book the conch is used as a trumpet to call everyone together and held by whoever is speaking at meetings, symbolically representing democracy and order. When a boulder released by Roger, Jack's lieutenant, smashes the conch, it is a sign that civilized order has fully collapsed since Jack's eventual increasing influence. At the same time, Piggy dies.

The famous Old English riddle Ic wæs be Sonde describes a conch: "I was by sound, near seawall, at ocean-stream; I dwelt alone in my first resting place. ... Little did I know that I, ere or since, ever should speak mouthless over mead-benches."

In popular folklore, it is believed that if one holds an open conch shell (or any other large marine snail shell) to the ear, the ocean can be heard. This phenomenon is caused by the resonant cavity of the shell producing a form of pink noise from the surrounding background ambiance. In reality, the person is hearing their blood flow in the capillaries of their ears; the sound enters the shell and reverberates through the chambers before coming back. This sound can also be heard (though rather poorly) by covering one's ear with one's hand. The rushing sound is the flow of blood.

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