The Calico clam shell has a distinctive brown-and-tan checkerboard or spotted pattern on the shell surface and the shell is glossy. The shells surface tends to be shiny with fine growth lines beneath the outer layer. They are normally 2–3 inches in size. The shell is a rounded to slightly oval shape. These features make them popular finds with beachcombers in south west Florida. The calico clam lives in shallow, sandy marine waters commonly found along sandy beach zones and areas near seagrass