Bittersweet Clam Shells of the Glycymerididae Family

Four Bittersweet Shells of the Glycymerididae Family can be found in this website:

Phylogeny: The Bittersweet Clam Shells of the Glycymerididae Family (Dall, 1908), are members of the order Arcida. The word “Glycimerididae” comes from the Greek words meaning “sweet part.” Shells in this order are characterized by having a straight hinge, with taxodont dentition. These shells are found exclusively in marine environments. There are two superfamilies in the Arcida order – Arcoidea and Limopsoidea.  Arcoidea are more quadrate while Limopsoideans tend to be oval in shape. The Glycymerididae Family falls in the superfamily Arcoidea. The Glycymerididae Family consists of one hundred seven species that have been placed in four genera – the Axinactis Genus with two species, the Glycymeris Genus with sixty-one species, the Melaxinaea Genus with one species, and the Tucetona Genus with forty-three species.  Glycymeridae is a synonym for this family, which is unaccepted because it is a misspelling, but it still can be found throughout the scientific literature. These shells are also commonly known as Bittersweet Shells and Dog Cockle Shells.

Description: Bittersweet Clam Shells are solid, equivalve, and inflated, with prominent beaks. They may be trigonal to circular in outline. Their hinge plate is broad and curved, with taxodont dentition.  There is a gap at both ends of the closed shell. These shells may be sculpted with coarse to fine radial ribs and/or commarginal striae. Shells in this family tend to be whitish, with varying amounts of tan to brown banding or blotching. The interior is porcelaneous and white with yellow to brown staining. Bittersweet Clam Shells are medium to large in size, with the larger species reaching 12.0 cm (4.7 inches) in length.

Habitat and Distribution: Bittersweet Clams are usually found in sand, mud, or fine gravel substrates. They are found in the intertidal zone and at depths in excess of 300 m (984 feet). Bittersweet Clam Shells have a global distribution in temperate to tropical seas, though most are found in warmer waters.

Natural History: Bittersweet Clams are suspension feeders that filter plankton and fine detritus from the surrounding water. In turn heir predators include birds, crabs, carnivorous mollusks and rays. They are gonochoric and reproduce sexually, through broadcast spawning, with external fertilization. For thousands of years Bittersweet Clams Shells have been collected as a food source, as tools, and as jewelry or decoration. They are still highly regarded as a food item because of their sweet taste.