''Pinctada radiata'', commonly known as the Atlantic pearl-oyster or the Gulf pearl oyster is a species of

pearl oyster ''Pinctada'' is a genus of saltwater oysters, marine bivalve mollusks in the family Pteriidae. These pearl oysters have a strong inner shell layer composed of nacre, also known as "mother of pearl". Pearl oysters are not closely related to ...

distributed throughout the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

and in the Mediterranean. Its range extends as far north as

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

and as far south as the Australian state of

Victoria Victoria most commonly refers to: * Queen Victoria (1819–1901), Queen of the United Kingdom and Empress of India * Victoria (state), a state of Australia * Victoria, British Columbia, Canada, a provincial capital * Victoria, Seychelles, the capi ...

Description

''P. radiata'' is generally between in length, though it can reach . The shell is thin, compressed, and square-like, with

growth ring Dendrochronology (or tree-ring dating) is the scientific method of dating tree rings (also called growth rings) to the exact year they were formed in a tree. As well as dating them, this can give data for dendroclimatology, the study of climate ...

s and ribs on the top surface. Its coloration varies, though it usually displays a brown or red exterior with a pearly interior and a light brown edge. More rarely, the shell may display a green or bronze exterior. Darker brown or red rays may mark the shell, creating darker areas at the margin. The shell's shape and structure also show much variation, hence its many synonyms; it has been described as "very similar to ''

Pinctada margaritifera ''Pinctada margaritifera'', commonly known as the black-lip pearl oyster, is a species of pearl oyster, a saltwater mollusk, a marine bivalve mollusk in the family Pteriidae. This species is common in the Indo-Pacific within tropical coral ree ...

''", and has been misidentified on occasion as ''P. margaritifera''. ''P. radiata'' is

hermaphroditic A hermaphrodite () is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic. The individuals of many ...

, with reproductive maturity being influenced by temperature.

Distribution

''Pinctada radiata'' occurs throughout the Indo-Pacific and

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 ...

at all depths, though it is generally found between . It attaches itself to various hard substrata, including rocks and wrecks. ''P. radiata'' is common throughout its range, possibly because of its adaptation to subtropical environments and ability to survive in polluted water. It was originally distributed only in the Indo-Pacific, but has been introduced into the Mediterranean unintentionally through the

Suez Canal The Suez Canal (; , ') is an artificial sea-level waterway in Egypt, Indo-Mediterranean, connecting the Mediterranean Sea to the Red Sea through the Isthmus of Suez and dividing Africa and Asia (and by extension, the Sinai Peninsula from the rest ...

and intentionally for

aquaculture Aquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. Nelu ...

Human uses

''Pinctada radiata'' is harvested for

pearl A pearl is a hard, glistening object produced within the soft tissue (specifically the mantle (mollusc), mantle) of a living Exoskeleton, shelled mollusk or another animal, such as fossil conulariids. Just like the shell of a mollusk, a pear ...

s, especially in

Qatar Qatar, officially the State of Qatar, is a country in West Asia. It occupies the Geography of Qatar, Qatar Peninsula on the northeastern coast of the Arabian Peninsula in the Middle East; it shares Qatar–Saudi Arabia border, its sole land b ...

i waters, where it may constitute up to 95% of the oyster catch. It is also caught for its edible flesh and lustrous shell. ''P. radiata'' has also been investigated for possible use as a

bioindicator A bioindicator is any species (an indicator species) or group of species whose function, population, or status can reveal the qualitative status of the environment. The most common indicator species are animals. For example, copepods and other sma ...

of heavy metals in

Persian Gulf The Persian Gulf, sometimes called the Arabian Gulf, is a Mediterranean seas, mediterranean sea in West Asia. The body of water is an extension of the Arabian Sea and the larger Indian Ocean located between Iran and the Arabian Peninsula.Un ...

waters.

References

{{Taxonbar, from=Q7194966 Pteriidae Bivalves of Australia Molluscs of Japan Molluscs of the Mediterranean Sea Molluscs of the Pacific Ocean Pearls Bivalves described in 1814