''Pecten jacobaeus'', the Mediterranean scallop, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

scallop Scallop () is a common name that encompasses various species of marine bivalve molluscs in the taxonomic family Pectinidae, the scallops. However, the common name "scallop" is also sometimes applied to species in other closely related famili ...

, an edible saltwater scallop, a marine

bivalve Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

in the family

Pectinidae Scallop () is a common name that encompasses various species of Marine (ocean), marine bivalve mollusc, molluscs in the Taxonomy (biology), taxonomic Family (biology), family Pectinidae, the scallops. However, the common name "scallop" is also ...

, the scallops.World Register of Marine species
/ref> Pectinidae - Pecten jacobaeus

Description

''Pecten jacobaeus'' usually reaches a length of about , but the world record size reaches over 210 mm.
/ref> The two valves have different shapes. The lower valve, with which the animal rests on the bottom, is very convex and light-colored, while the upper valve is flat and brown. They show 14 to 16 ribs (radial wrinkles) with a more or less rectangular cross section. The inside of the valves is porcelain-like smooth. The mollusc has at the edge of the mantle many short tentacles, between which there are a total of 60 blue-millimeter lens eyes. By quickly closing of the two valves it can swim away several meters in case of danger. These scallops eat

plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...

ic organisms and other floating food particles, which they obtain by filtering sea water with their

gill A gill () is a respiration organ, respiratory organ that many aquatic ecosystem, aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow r ...

Distribution

This species appears to be endemic to the

Mediterranean Sea The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

, but it may be conspecific with '' Pecten maximus'', the great scallop, which has a larger distribution. Although these two species are morphologically similar, they present distinguishing features. Fossils of ''Pecten jacobaeus'' first appear at the beginning of the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

deposits of Italy.

Commercial value

Scallops of this species are collected commercially for human consumption using such techniques as the Rapido trawl.

Popular culture

In a Christian context, this species is traditionally associated with Saint James, also known as

James, son of Zebedee James the Great ( Koinē Greek: Ἰάκωβος, romanized: ''Iákōbos''; Aramaic: ܝܥܩܘܒ, romanized: ''Yaʿqōḇ''; died AD 44) was one of the Twelve Apostles of Jesus. According to the New Testament, he was the second of the apostles t ...

, also known as Saint Jacob, hence the specific name ''jacobaeus''. It is also known as the "Pilgrim's scallop", as the shells were used by the pilgrims in the Middle Ages as a cup.

References

* C. Linnaeus. 1758. Systema Naturae per Regna Tria Naturae, secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentiis, Synonymis, Locis. Tomus I. Editio decima, reformata. Laurentii Salvii, Holmiae (Lars Salvius, Stockholm) * Guido T. Poppe und Y. Goto: European Seashells. Vol II (Scaphopoda, Bivalvia, Cephalopoda). 221 S., Verlag Christa Hemmen, Wiesbaden, 1993

External links