Scallop

Scallop
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Bivalvia
Order:	Ostreoida
Suborder:	Pectinina
Superfamily:	Pectinoidea
Family:	Pectinidae Rafinesque, 1815
Genera
See text.

A scallop (Template:PronEng or /ˈskæləp/) is a marine bivalve mollusc of the family Pectinidae. Scallops constitute a cosmopolitan family, found in all of the world's oceans. Many scallops are highly prized as a food source. Some scallops are valued for their brightly colored shells.

Like the true oysters (family Ostreidae), scallops have a central adductor muscle, and thus the inside of their shells has a characteristic central scar, marking the point of attachment for this muscle. The adductor muscle of scallops is larger and more developed than that of oysters, because they are active swimmers; scallops are in fact the only migratory bivalve. Their shell shape tends to be highly regular, recalling one archetypal form of a seashell, and because of this pleasing geometric shape, the scallop shell is a common decorative motif.

Most scallops are free-living, but some species can attach to a substrate by a structure called a byssus, or even be cemented to their substrate as adults (e.g. Hinnites spp.). A free-living scallop can swim, by rapidly opening and closing its shell. This method of locomotion is also a defense technique, protecting it from threatening predators. There can sometimes be an audible soft popping sound that some scallops make as they flap their shells underwater, and because of this, one kind was dubbed "singing scallops" by a seafood vendor.

Life cycle

File:IMGP0789.jpg

A live specimen of Argopecten irradians, the Atlantic Bay scallop, photographed at the Marine Biological Laboratory in Woods Hole, Massachusetts

Scallops are hermaphroditic; capable of switching sexes. Both sexes produce roe, whose coloring depends upon the parent's (current) sex. Red roe is that of a female, and white, that of a male. Spermatozoa and ova are released freely into the water during mating season and fertilized ova sink to the bottom. After several weeks, the immature scallop hatches and the larvae drift until settling to the bottom again to grow. They reach sexual maturity after several years, though they may not reach a commercially harvestable size until six to eight years of age. Scallops may live up to 18 years, with their age reflected in the annuli, the concentric rings of their shells.

On the east coast of the U.S., the availability of bay scallops has been greatly diminished by the overfishing of sharks in the area. A variety of sharks have, until recently, fed on rays, which are a main predator of bay scallops. With the shark population reduced, in some places almost totally, the rays have been free to dine on scallops to the point of greatly decreasing their numbers.

Taxonomy and list of genera

In total, in the family Pectinidae, there are more than 30 genera and around 350 species. While species are generally well circumscribed, their attribution to subfamilies and genera is sometimes equivocal, and there is minimal information about phylogeny and relationships of the species, not least because most work has been based on adult morphology (Barucca et al., 2004).

The great scallop, Pecten maximus, on the right, next to the native European oyster, Ostrea edulis.

Aviculopecten subcardiformis; an extinct pectenoid from the Logan Formation (Lower Carboniferous) of Wooster, Ohio (external mold).

Pecten sp. with serpulid worm encrusters; Duck Harbor Beach on Cape Cod Bay, Wellfleet, Massachusetts.

Genera

• Aequipecten Fischer, 1886 (includes Rough scallop Aequipecten muscosus)
• Amusium Bolten, 1798
• Anguipecten Dall, Bartsch & Rehder, 1938
• Annachlamys Iredale, 1939
• Argopecten Monterosato, 1889 (includes bay scallop, Argopecten irradians, Atlantic calico scallop Argopectin gibbus and Pacific calico scallop, Argopecten ventricosus)
• Bathypecten Schein-Fatton 1985
• Bractechlamys Iredale, 1939
• Catillopecten Iredale, 1939
• Chlamys Bolten, 1798 includes Queen scallop, Chlamys opercularis
• Coralichlamys Iredale, 1939
• Cryptopecten Dall, Bartsch & Rehder, 1938
• Decatopecten Sowerby, 1839
• Delectopecten Stewart, 1920
• Equichlamys Iredale, 1929
• Euvola Dall, 1898
• Excellichlamys Iredale, 1939
• Flexopecten Sacco, 1897
• Glorichlamys Dijkstra, 1991
• Gloripallium Iredale, 1939
• Haumea Dall, Bartsch & Rehder, 1938
• Hyalopecten Verrill, 1897
• Juxtamusium Iredale, 1939
• Lissopecten Verrill, 1897
• Mesopeplum Iredale, 1929
• Mimachlamys Iredale, 1929
• Minnivola Iredale, 1939
• Mirapecten Dall, Bartsch & Rehder, 1938
• Nodipecten Dall, 1898
• Notochlamys Cotton, 1930
• Patinopecten Dall, 1898
• Pecten Müller, 1776 (includes the Great or King scallop, Pecten maximus, Japanese (sea) scallop, Pecten yessoensis, and the New Zealand scallop, Pectin novaezealandiae)
• Pedum Bruguière, 1791
• Pseudohinnites Dijkstra, 1989
• Semipallium Lamy, 1928
• Serratovola Habe, 1951
• Sinepecten Schein, 2006 [1]
• Somalipecten Waller, 1986
• Veprichlamys Iredale, 1929
• Volachlamys Iredale, 1939

Gathering scallops

Scallops were traditionally caught by dragging the seabed, but now in British seas there is a trade in scuba diving to catch scallops. Dived scallops tend to fetch better prices than dredged scallops because they are out of the water for less time, meaning they get to the consumers' plate quicker. When scallops are dredged, they may spend up to 2 weeks on a vessel before they get to market. Like any seafood, the meat will start to break down in time.

Scallops in cooking

File:Singing Scallops.jpg

Scallops on display in a seafood market

Scallops are a popular type of shellfish in both Eastern and Western cooking. They are characterised by having two types of meat in one shell: the adductor muscle, called "scallop" which is white and meaty, and the roe, called "coral", which is red or white and soft.

In Western cuisine, scallops are commonly sautéed in butter, or else breaded and deep fried. Scallops are commonly paired with light semi-dry white wines. In the U.S., when a scallop is prepared, usually only the adductor muscle is used; the other parts of the scallop surrounding the muscle are ordinarily discarded. Sometimes markets sell scallops already prepared in the shell with only the adductor muscle intact. Outside the U.S. the scallop is often sold whole.

Scallops that are without any additives are called "dry packed" while scallops that are treated with sodium tripolyphosphate (STP) are called "wet packed". STP causes the scallops to absorb moisture prior to the freezing process, thereby getting a better price per unit of weight. The freezing process takes about two days.

In continental cuisine, scallops are often prepared in the form of a quiche or cooked and then set into a savory custard. In Japanese cuisine, scallops may be served in soup or prepared as sashimi or sushi. Dried scallop is known in Oriental cuisine as conpoy.

In a sushi bar, hotategai (帆立貝, 海扇) is the traditional scallop on rice, and while kaibashira (貝柱) may be called scallops, it is actually the adductor muscle of any kind of shellfish, e.g. mussels, oysters, or clams.

Scallops have lent their name to the culinary term scalloped, which originally referred to seafood creamed and served hot in the shell (Rombauer 1964). Today it means a creamed casserole dish such as scalloped potatoes, which contains no seafood at all.

Potato scallops are also a popular 'chip shop' dish in the UK. A thick potato slice is covered in batter and deep fried.

Symbolism

Shell of Saint James

The scallop shell is the traditional emblem of Saint James the Greater and is popular with pilgrims on the Way of St James to the apostle's shrine at Santiago de Compostela in Spain. Medieval Christians making the pilgrimage to his shrine often wore a scallop shell symbol on their hats or clothes. The pilgrim also carried a scallop shell with him and would present himself at churches, castles, abbeys etc. where he could expect to be given as much sustenance as he could pick up with one scoop. Probably he would be given oats, barley, and perhaps beer or wine. Thus even the poorest household could give charity without being overburdened. The association of Saint James with the scallop can most likely be traced to the legend that the apostle once rescued a knight covered in scallops. An alternate version of the legend holds that while St. James's remains were being transported to Spain from Jerusalem, the horse of a knight fell into the water, and emerged covered in the shells.

• The German word for scallop is "Jakobsmuschel".
• The Swedish word for scallop literally translates to pilgrim mussel.
• A French name for a dish containing scallops is coquille St. Jacques (in Québec, pétoncle is more commonly used).
• The Dutch name is Jakobsschelp (James being English for Jacobus).
• In Danish, ibskal refers to scallops worn by pilgrims from Santiago de Compostella (Ib being the Danish name for St. James)
• The Italian word for scallop is "Pettine di mare" which literally means "sea comb"

Fertility symbol

Aphrodite in a sea shell, from Amisos, now in the Louvre.

One legend of the Way of St James holds that the route was seen as a sort of fertility pilgrimage, undertaken when a young couple desired to bear offspring; the scallop shell is believed to have originally been carried therefore by pagans as a symbol of fertility.

Many paintings of Venus, the Roman goddess of love and fertility, included a scallop shell in the painting to identify her; this is evident in Botticelli's classically inspired The Birth of Venus (which has even been nicknamed "Venus on the half-shell").

Alternatively, the scallop resembles the Setting Sun, which was the focus of the pre-Christian Celtic rituals of the area. To wit, the pre-Christian roots of the Way of St. James was a Celtic death journey westwards towards the setting sun, terminating at the End of the World (Finisterra) on the "Coast of Death" (Costa de Morta) and the "Sea of Darkness" (ie, the Abyss of Death, the Mare Tenebrosum, Latin for the Atlantic Ocean, itself named after the Dying Civilization of Atlantis). The reference to St. James rescuing a "knight covered in scallops" is therefore a reference to St. James healing, or resurrecting, a dying (setting sun) knight. Similarly, the notion of the "Sea of Darkness" (Atlantic Ocean) disgorging St. James' body, so that his relics are (allegedly) buried at Santiago de Compostella on the coast, is itself a metaphor for "rising up out of Death", that is, resurrection.

Heraldry

A scallop shell as a heraldic device on a German coat of arms.

The scallop shell symbol found its way into heraldry as a badge of those who had been on the pilgrimage to Compostela, although later it became a symbol of pilgrimage in general. Winston Churchill's family coat of arms includes a scallop, another example is the surname Wilmot and also John Wesley's (which as a result the scallop shell is used as an emblem of Methodism). However, charges in heraldry do not always have an unvarying symbolic meaning, and there are cases of arms in which no family member went on a pilgrimage and the occurrence of the scallop is simply a pun on the name of the armiger, or for other reasons.

State Shell of New York

The U.S. state of New York made the Atlantic bay scallop its state shell in 1988.

Scallops in design

In design Scalloped edges or ridges refers to a wavy pattern reminiscent of the edge of a scallop's shell.

References

• Rombauer, Irma S. and Marion Rombauer Becker (1931 [1964]) The Joy of Cooking, p 369. Indianapolis: Bobbs-Merrill. ISBN 0-452-25665-8.
• Barucca M, Olmo E, Schiaparelli S, Canapa A (2004) Molecular phylogeny of the family Pectinidae (Mollusca: Bivalvia)

External links

• Bay Scallops - Cooking, eating, shucking, and harvesting with pictures and video
• Biology Photo of the Month: Scallop eyes
• Alaska Department of Fish and Game
• Research on Bay Scallop Aquaculture and Enhancement
• The Scallop
• Classification of Pectinoidea (Propeamussiidae and Pectinidae) - includes partly different genera, with subfamilies and tribes.
• Too Few Jaws: Shark declines let rays overgraze scallops -- Science News Online, March 31, 2007