I'VE BOUGHT MANY CYPRAEA FROM THE PHILIPPINES THAT HAVE FOREIGN GROWTHS
RANGING FROM CORAL(ALSO BLACK CORAL), BIVALVES, BARNACLES, CREPIDULA, OR
SPONGE. ALWAYS THE MARGINAL LINE(WHERE THE 2 MANTLES MEET)IS DISTORTED. I
BELIEVE NATURAL PREDATORS DAMAGE THE MANTLE THAT CAUSES THE IRREGULAR
MARGINAL LINE. THIS CAUSES SURFACE AREAS OF THE CYPRAEA TO BE OPEN TO
FOREIGN GROWTH & IRREGULAR CALCIFYING.    ALOHA ALL!  CHRIS:) c",)