4a. Girdle is covered in close-set oval scales or granules. Valves have a distinct beak. Girdle and valves light red, pink, or orange with mottled patterns of cream, including cream stripes across the girdle.
4b. Girdle is leathery. Valves have no beak, or an indistinct beak. Girdle and valves light red to brick red with mottled patterns of cream and brown.