Shell Penetration and Feeding by Naticacean and Muricacean Predatory Gastropods: A Synthesis

Predatory gastropod shell borers occur among the Capulidae, Naticacea, Tonnacea, Muricacea, and Vayssiereidae. With the exception of boring nudibranchs, all known gastropod borers are shelled. This synthesis is concerned primarily with naticacean and muricacean borers that excavate smooth, round, beveled holes. They occur in every coastal region of the world that has been examined, and identify prey chemoreceptively. The shell penetrating mechanism includes at least an accessory boring organ (ABO) and radula. The ABO is located in three separate anatomical regions in different groups of borers: in muricaceans, in the sole of the foot anterior to the ventral pedal gland or atop the ventral pedal gland; in naticaceans, under the tip of the proboscis. Studies of the ABO of several species of naticacean and muricacean snails reveal a common ultrastructural form. An acid (possibly HCl) and unidentified chelating agents and enzymes in a hypertonic mucoid secretion released by the ABO are hypothesized to dissolve shell during hole boring. All 33 species of naticacean and muricacean snails examined possess an ABO and are shell borers.