Sitka (Alaska) to San Diego; uncommon south of Point Conception.

Ceratostoma foliatum is a carnivorous snail that eats mainly barnacles such as Semibalanus cariosus and Balanus glandula, and bivalves such as Protothaca staminea, Mytilus californianus, and Mytilus trossulus. It drills through their protective shell with its radula. After drilling through the shell Ceratostoma foliatum injects digestive enzymes into the prey’s body cavity and sucks out the dissolved tissue.

Sexes are separate and may form large groups during spring copulation. After copulation, females lay their eggs in a communal mass nearby in stalked, yellow, flattened egg cases about 13 mm long, attached to rocks. Each capsule has about 50 orange eggs and each female lays about 40 capsules per year.

Larval stages occur within the capsule, and the snails hatch as juveniles after 4-10 months. Matures in about 4 years and can live 16 years. Individuals older than this may have shells which have eroded so much at the apex that they are shorter than younger individuals (16-year olds may be only 5-6 cm long).

Showing the single result

Show sidebar