The Portuguese oyster, Crassostrea gigas, is a species of oyster found in the southwest Iberian Peninsula, closely related to the Pacific oyster. Although first identified as a native European species, genetic studies have suggested that the Portuguese oyster originated from the Pacific coast of Asia and was introduced to Europe by Portuguese trading ships in the 16th century. The species is usually found in coastal river mouths and estuaries.
Prior to decimation by iridoviral disease in 1969, C. gigas was extensively cultivated in France and Portugal as part of the edible oyster industry. The Pacific oyster, which is more resistant to the disease, was introduced in the 1970s and have since replaced C. gigas as the main commercial species. Currently, the Portuguese oyster is not cultured commercially.
- , Lapegue S, et al. 2004. Evidence for the presence of the Portuguese oyster, Crassostrea angulata, in northern China. Journal of Shellfisheries Research.
- , Michinina S and Rebordinos L. 1997. Genetic differentiation in marine and estuarine natural populations of Crassostrea angulata. Marine Ecology Progress Series.
- , Boudry P et al. 1998. Differentiation between populations of the Portuguese oyster, Crassostrea angulata (Lamark) and the Pacific oyster, Crassostrea gigas (Thunberg), revealed by mtDNA RFLP analysis. Journal of Experimental Marine Biology and Ecology.
- , Gill Disease of Portuguese oysters. Fisheries and Oceans Canada.