California Venus Clam Shell, Chione californiensis
California Venus Clam Shell, Chione californiensis. Shell collected off the beach at Punta Chivato, Baja California Sur, December 2021. Size: 6.6 cm (2.6 inches) x 5.8 cm (2.3 inches). Collection, photographs and identification courtesy of Colin Campbell, DVM, Punta Chivato, Baja California Sur.
Phylogeny: The California Venus Clam, Chione californiensis (Broderip, 1835), is a bivalve mollusk that is a member of the Veneridae Family of Venus Clams. The genus Chione is one of one hundred seven genera in this family, and there are eleven species in this genus. They are known in Mexico via many common names in Mexico, including: Almeja Arenosa, Almeja Arrocera, Almeja China, Almeja Marinera, Almeja Piedrera, Almeja Rosa, Almeja Roñosa, Chirla, and Venus Mantecosa.
Description: The California Venus Clam shell has a rounded triangular outline. The shells are fairly thick and moderately inflated. The exterior is sculpted with high, thin, concentric ridges and very fine radial ribs. The exterior is white with irregular brown flecks. The interior is white, with many specimens showing blue or purplish tinge near the beak and posterior. The California Venus Clam reaches a maximum of 8.2 cm (3.2 inches) in length, and 7.8 cm (3.1 inches) in height. The California Venus Clam is easily confused with the Frilled Venus, Chione undatella or Almeja Roñosa del Golfo de Baja California (thinner and narrow spaced concentric ribs).
Habitat and Distribution: The California Venus Clam is found within sand and mud substrate from the intertidal zone to depths up to of 70 m (230 feet). They are a temperate and tropical Eastern Pacific species. In Mexican waters they range from the northern border to Acapulco, Guerrero, including the entire Gulf of California.
Ecology and Behavior: California Venus Clams are suspension feeders that feed primarily on phytoplankton. They are prey for gastropods, sea stars, and shore birds. They are gonochoric and reproduce sexually, through broadcast spawning. There is no mention in the available literature of them engaging in any types of parasitic, commensal, or symbiotic relationships. They are edible and are harvested commercially, recreationally, and by artisan fisheries. They have been an important food source to indigenous people for thousands of years. From a conservation perspective they have not been formally evaluated however they are fairly common with a relatively wide distribution and should be consider to be of Least Concern.
Synonyms: Chione allisoni, Chione californiensis durhami, Chione californiensis gealeyi, Chione californiensis peabodyi, Cytherea undatostriata, Venus californiensis, Venus leucodon, Venus nuttalli, and Venus succincta.