Oyster Mushrooms (Pleurotues Ostreatus) are so named for their similarity in color and shape to the Mollusk. Oyster mushrooms are cultivated, though they can be found in the wild. Oysters have a mild mushroom flavor, firm texture, and are a popular ingredient in many Asian dishes. Oyster mushrooms have a sea shell type shape with a pale yellow creamy color. These are the whole Oyster Mushroom.