The famed Sydney Rock oyster (Saccostrea commercialis), has a smaller, rougher, longer shell than the Pacific or Japanese oyster (Crassostrea gigas). Both varieties, which are farmed commercially, are available and are good to eat all year round. A third variety, becoming increasingly available, is the Native Flat oyster (Ostrea angasi) which is also grown commercially.
Oyster from natural oyster beds, found along Australian sea shores and estuaries, have the best flavor in the cooler months. Pacific oysters breed differently, so they taste agreeable all year round.
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