Jackknife Clam Shells of the Solenidae Family

One Jackknife Clam Shell of the Solenidae Family can be found in this website:

Gemmelli’s Jackknife Clam Shell, Solen gemmelli. A representative of the Solenidae Family of Jackknife Clam Shells.

Phylogeny: Jackknife Clam Shells in the Solenidae Family are bivalve mollusks in the Adapedonta order. The two superfamilies in this order are Hiatelloidea and Solenoidea. Solenoidea consists of two families – Pharidae and Solenidae. These two families are distinguished by the number of cardinal teeth on their hinge. The Solenidae Family consists of three genera – Neosolen, Solen, and Solena.  There are seventy species total in the Solenidae Family, of which sixty-seven are in the Solen Genus. The name Solen refers to the flattened cylindrical shape of these shells and comes from the Greek word for pipe. Shells in this family are also commonly known as Razor Clams or Solenids.

Description: Jackknife Clam Shells have elongated oval or quadrate outlines. These shells are inequilateral, and have a gap between valves at both ends. The shells are thin and fragile. Any visible sculpting consists of weak commarginal growth lines. The hinge plate is weak, with one cardinal tooth. They may have a thick or thin periostracum. They are most frequently solid white or gray in color, with some showing a pink or purple wash. Jackknife Clam Shells reach a maximum of 30 cm (11.7 inches) in length, although most species are a fraction of that size.

Habitat and Distribution: Jackknife Clam Shells are usually found buried in sand or mud, in the intertidal zone and to depths of 100 m (328 feet). Shells in the Solenidae Family are found worldwide in temperate to tropical seas. Seven seven species from this family are found in Mexican waters.

Natural History: Jackknife Clam Shells are infaunal suspension feeders that feed primarily on plankton and suspended organic matter. They are well adapted for swift and deep burrowing. In turn, they are prey for fish, crabs, other mollusks, and marine mammals. Jackknife Clam Shells are gonochoric and reproduce sexually through broadcast spawning. They are harvested as a human food source or as of use as a fishing bait in many parts of the world.