Haustrum scobina, or the oyster borer, is a species of predatory sea snail, a marine gastropod mollusk in the family Muricidae, the murex snails or rock snails. Oyster borers use a mucous layer that surrounds the entrance to their shell to prevent dessiccation in the midlittoral and high tidal zones. Oyster Borers are frequently found in crevices which have more protection from predators, higher water availability, lower temperature, extremes in salinity and protection from the sun and wind.