California Sunset Clam Shell, Gari californica
California Sunset Clam Shell, Gari californica. Shell collected from the beach in the greater San Diego area, San Diego California, February 2014. Size: 5.8 cm (2.3 inches) x 3.3 cm (1.3 inches). Collection, photograph and identification courtesy of Bob Hillis, Ivins, Utah.
Phylogeny: The California Sunset Clam Shell, Gari californica (Conrad, 1849), is a bivalve mollusk that is a member of the Psammobiliidae Family of Sunset Clam Shells. The genus Gari is one of ten genera in this family, and there are fifty-six species in this genus. The genus name Gari is thought to come from the Latin word Garum, meaning fish sauce or pickled shellfish.
Description: California Sunset Clam Shells are thin, slightly inflated, and have a subquadrate outline. The posterior end of the shell is broadly rounded to truncate (having a cropped appearance). The anterior end is broadly rounded. The shell has a low beak. The exterior surface has fine concentric ridges. The exterior of the shell is whitish to tan in color, with pink rays. The interior is white. They are covered with a thin brown periostracum. California Sunset Clam Shells reach a maximum of 15.0 cm (5.9 inches) in length.
Habitat and Distribution: California Sunset Clams are found in sand and gravel along exposed coastlines, and in sandflats at the entrance to bays and lagoons. They live in the intertidal zone, and at depths up to 170 m (558 feet). Their burrows are 15-20 cm (6-8 inches) deep. They are a temperate to subtropical Eastern Pacific species that have a limited distribution in Mexican waters of the Pacific Ocean being found only north of Magdalena Bay, Baja California Sur, along the central and northwest coasts of the Baja Peninsula.
Ecology and Behavior: California Sunset Clams are a poorly studied and understood species. There is very limited documentation of their diet, predation, reproduction or ecosystem interactions. Other species in the Psammobiidae Family are suspension feeders or deposit feeders, using their siphons to suck up plankton and detritus that drifts by or that is laying on the surface of the substrate. They are a facultatively mobile infaunal species and therefore able to move to food sources. They are gonochoric and reproduce sexually, through broadcast spawning, with external fertilization. Their engagement in any type of commensal, parasitic, or symbiotic relationships has not been formally documented. From a conservation perspective the California Sunset has not been formally evaluated. However, they are fairly common with a wide distribution and should be considered to be of Least Concern.
Synonyms: Gari (Gobraeus) californica, Gari (Psammocola) californica, Psammobia californica, Psammobia lilacina, and Psammobia rubroradiata.