Silken Scallop Shell, Leopecten sericeus

Silken Scallop Shell, Leopecten sericeus. Size: 6.4 cm (2.6 inches) x 7.0 cm (2.8 inches). Shell collected from within the estuary of the Magdalena Bay complex, Baja California Sur, October 2018.

Phylogeny: The Silken Scallop Shell, Leopecten sericeus (Hinds, 1845), is a bivalve mollusk that is a member of the Pectinidae Family of Scallop Shells. The genus Leopecten is one of sixty-four genera in this family, and there are five species in this genus. They are known in Mexico as Vieira de Satinada.

Description: The Silken Scallop Shell is a classic fan-shaped scallop with a rounded outline, a flattened profile, a straight hinge, and equal-sized ears (auricles). Both valves are sculpted with pronounced triangular radiating ribs, with the spaces between the ribs wider than the ribs. They also have fine commarginal striae. The right valve is moderately convex and the left valve is flat or slightly concave. The right valve is white to light orange or brown in color. The left valve is reddish brown, with white maculations. Silken Scallop Shells reach a maximum of 8.8 cm (3.5 inches) in length and 8.0 cm (3.1 inches) in height.

Habitat and Distribution: Silken Scallops are found on sand and mud substrates,  from the intertidal zone to depths up to 180 m (600 feet). They are a subtropical to tropical Eastern Pacific species that are found in all Mexican waters of the Pacific Ocean, including the Revillagigedo Islands, with the exception that they are absent from the west coast of the Baja Peninsula and north of Bahía de Los Ángeles, Baja California, in the Sea of Cortez.

Ecology and Behavior:  Silken Scallops are suspension feeders that feed primarily on plankton and suspended organic matter. 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 formulated. From a conservation perspective the Silken Scallop has not been formally evaluated. However, they are fairly common with a relatively wide distribution and should be considered to be of Least Concern.  

Synonyms:  Pecten sericeus.