Giant Pacific Cockle Shell, Leavicardium elatum
Giant Pacific Cockle Shell, Leavicardium elatum. Shell collected off the beach of Punta Chivato, Baja California Sur, June 2025. Size: 10.9 cm (4.3 inches) x 8.6 cm (3.4 inches) x 4.0 cm (1.6 inches). Collection, photographs and identification courtesy of Colin Campbell, DVM, Punta Chivato.
Giant Pacific Cockle Shell, Laevicardium elatum. Shell collected off the beach of Punta Chivato, Baja California Sur, June 2025. Size: 13.9 cm (5.5 inches) x 11.8 cm (4.6 inches) x 6.1 cm (2.4 inches). Collection, photographs and identification courtesy of Colin Campbell, DVM, Punta Chivato.
Phylogeny: The Giant Pacific Cockle Shell Laevicardium elatum (G.B. Sowerby I, 1833) is a member of the Cardiidae Family of Cockles and True Cockle Shells. This species is in the Laevicardiinae Subfamily. The Laevicardium Genus is one of two genera in the Laevicardiinae Subfamily, and there are fifteen species in the Laevicardium Genus. The genus name Laevicardium is a combination of Greek and Latin words meaning “smooth heart”. This refers to the shells in this genus lacking the pronounced radial ribs of other genera in this family. The species name elatum is Latin and can mean “tall”, “elevated”, “lofty”, or “exalted.” They are also known as the Giant Egg Cockle and the Yellow Cardinal Cockle and in Mexico as as Almeja Botijona and Berberecho Gigante. In the Seri culture they are called Xtiip.
Description: Giant Pacific Cockle Shells are ovate to trigonal in outline, and strongly inflated in profile. The beak is high and the hinge plate is strong and broad. The exterior is sculpted with 45 to 48 low, rounded, radial ribs. The interior is smooth, except for fine crenulations around the anterior and ventral margins. These shells are yellowish to brownish in color, with a white interior. They have a thick, brown periostracum. Giant Pacific Cockle Shells are fairly large and reach a maximum of 19.0 cm (7.4 inches) in length.
Habitat and Distribution: Giant Pacific Cockle Shells are found buried in sand and mud substrates. They live in the intertidal zone and to depths of 30 m (98 feet). Giant Pacific Cockle Shells are a subtropical to tropical Eastern Pacific species that are found in all Mexican waters of the Pacific Ocean.
Ecology and Behavior: Giant Pacific Cockle Shells are suspension feeders that feed primarily on plankton and other suspended organic matter. They are eaten by fish, sea stars, crabs, and gastropods. They are simultaneous hermaphrodites (having both male and female reproductive organs) and reproduce sexually, through broadcast spawning, with external fertilization. Giant Pacific Cockle Shells are suspected of hosting endoparasitic trematode flatworms, which live in their gonad and impact reproductive success. Their engagement in any type of commensal or mutualistic relationships has not been formally documented. For thousands of years these shells have been harvested by indigenous peoples as a food source, a tool, and trade good. They continue to be harvested by artisanal and commercial fisheries. From a conservation perspective the Giant Pacific Cockle Shells have not been formally evaluated however, they are fairly common with a relatively wide distribution and should be considered to be of Least Concern.
Synonyms: Cardium elatum and Fulvia (Laevifulvia) ballieni.