 Similar techniques are used in different parts of the world to cultivate other species including the Sydney rock oyster ( <unk> <unk> ) , the northern quahog ( Mercenaria mercenaria ) , the blue mussel ( Mytilus edulis ) , the Mediterranean mussel ( Mytilus <unk> ) , the New Zealand green @-@ lipped mussel ( Perna <unk> ) , the grooved carpet shell ( <unk> <unk> ) , the Japanese carpet shell ( <unk> <unk> ) , the pullet carpet shell ( <unk> <unk> ) and the <unk> scallop ( <unk> <unk> ) . 
