 |
| A | B | C | D |
Shells "A" measure aprox 30mm in height.
| Cerastoderma edule (top) | Cerastoderma glaucum (bottom) | |
| rounded shape | A | more angular shape |
| more flattened ribs | A | more prominent ribs |
| slightly thicker shell | A | slightly thinner shell |
| long hinge | B | short hinge |
| wavy posterior valve margins | C | straight posterior valve margins |
| interior ribs near margins only | D | interior ribs throughout shell |
| diffuse stain near anterior margin | D | well defined stain near anterior margin |