Pinctada margaritifera

Black-lip pearl oyster
Live individual on display in the Aquarium Finisterrae
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Bivalvia
Order:	Pterioida
Family:	Pteriidae
Genus:	Pinctada
Species:	P. margaritifera
Binomial name
Pinctada margaritifera (Linnaeus, 1758)

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

The ability of P. margaritifera to produce pearls means that the species is a valuable resource to humans. The oysters are harvested wild from coral reefs and are also commonly grown in aquaculture, both primarily taking place in the Indo-Pacific region.

The common name of this species refers to the black coloring along the margins of the interior of the shell. Externally the shell is dark grayish brown or green, though white spots are common across the shell. Adults usually reach between 20 and 25 centimetres (7.9 and 9.8 in) in height. A distinctive feature of the species is that the hinge has no teeth.

(The genera Pinctada and Pteria are often confused. In Pinctada, the hinge is long and straight, the long end of the shell forms a right angle to the hinge, and the left valve is slightly deeper than the right. In the genus Pteria, the shell width is much longer than its height and the angle of the hinge is prominent and pronounced.)

Pinctada margaritifera occupies a wide range throughout the Persian Gulf, Red Sea, Sudan, Papua New Guinea, Australia, French Polynesia, Cook Islands, Indonesia, Andaman and Nicobar Islands, Southwestern part of the Indian Ocean, Japan and the Pacific Ocean, and various locations on the coast of India.

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Wikipedia