Individuals of Crepidula adunca (Mollusca, Gastropoda) avoid shared doom through host specificity

► Crepidula adunca may avoid shared doom by using Calliostoma ligatum as a host. ► Field trials: predators consumed more Margarites pupillus than Calliostoma ligatum. ► Laboratory trials: common predators preferred M. pupillus to Calliostoma ligatum. ► Calliostoma ligatum is faster than M. pupillus when stimulated by Leptasterias hexactis. ► Body size affected speed in Calliostoma ligatum but not in M. pupillus.