Predation by Gastropods of the Family Ranellidae (= Cymatiidae): A Pan-Tropical Issue for Marine Bivalve Aquaculture

This review illustrates various aspects of the life cycle of some species of gastropods belonging to the Ranellidae. These species possess a series of characteristics that allow for the wide dispersal of their larval stages (planktotrophic). Combined with their high fecundity and the effectiveness of their predatory behavior, this results in high mortalities of cultivated marine bivalves, both under suspended conditions in the water column and on the seabed. The different organs of their alimentary system and their functions are described. Further, the various strategies and methods developed to control the incidence of these predators in bivalve cultures are detailed. Among the most evident characteristics of most species are: (1) Parental care provided by the egg-laying mother over the egg capsule mass, ensuring effective larval hatching; (2) Indirect larval development, which includes a planktotrophic larva with swimming capability through a velum that allows for geographical expansion; (3) Predatory activity carried out through an alimentary system composed of modified salivary glands that produce biotoxins and a pleuroembolic (eversible) proboscis capable of inoculating the toxins, which quickly incapacitate or kill their prey without needing to perforate their shells, enhancing their predatory capacity.