Concave Scallop Shell, Euvola vogdesi

Concave Scallop Shell, Euvola vogdesi. Shell collected from within the estuary of the Magdalena Bay complex, Baja California Sur, October 2018. Size: 6.6 cm (2.6 inches) x 7.0 cm (2.8 inches).

Phylogeny: The Concave Scallop, Euvola vogdesi (Arnold, 1906), is a bivalve mollusk that is a member of the Pectinidae Family of Scallop Shells. The genus Euvola is one of sixty-four genera in this family, and there are ten species in this genus. This species is also known as the Mexican Deep Scallop and the Vogde’s Scallop and in Mexico as Almeja Voladora and Viere de Vogde. Their Mexican common name “Volador” or flyer, stems from their ability to swim rapidly by a quick opening and closing of their valves. This species was named in honor of Andrew Wayne Vogdes, a famous Paleontologist and a significant player in the history of the San Diego Natural History Museum.

Description: The Concave Scallop shell has a slightly concave left valve and a very convex right value for which it is named. The left valve has radiating flat ribs and the right valve has rounded ribs. The shell has an overall reddish-brown exterior and the right valve has a buffy yellow to orange tinge.  Concave Scallops reach a maximum length of 11.7 cm (4.6 inches) and 10.7 cm (4.2 inches) in height.

Habitat and Distribution: Concave Scallops are found over and within sand and mud substrate. They live in the intertidal zone, and to depths of 155 m (510 feet).  Concave Scallops are a subtropical to tropical Eastern Pacific Species. They are found along the entire west coast of Mexico, including the entire Gulf of California.

Ecology and Behavior: Concave Scallops are suspension feeders that feed primarily on plankton. They are gonochoric and reproduce sexually, through broadcast spawning, with external fertilization.  There is no mention in the available literature of them engaging in any types of parasitic, commensal, or symbiotic relationships. Concave Scallops are edible and are farmed, fished and sold commercially. 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: Argopecten vogdesi, Argopecten vogdesi vogdesi, Oppenheimopecten vogdesi, Pecten (Euvola)  cataracts, Pecten dentatus, Pecten excavatus,  and Pecten (Pecten) vogdesi.