Ensis directus

] Atlantic jackknife also known as the bamboo clam, American jackknife clam or razor clam - Ensis directus'''

Habitat Sandy and muddy bottoms of bays and estuaries, intertidal and subtidal zones.

Range Found on the North American Atlantic coast, from Canada to South Carolina. The clam has also been introduced to Europe.

Description A large species of edible marine marine bivalve mollusc. Up to 10 inches; approximately six times longer than wide. Razor clams are narrow and said to resemble an old-fashioned barber's straight-edged razor. The glossy shell has a purple region near the curving edge and looks glossy. The shell may also look brownish green in color. The cream-colored muscular foot protrudes approximately 5 inches from the shell when extended. A siphon is present which is a tube-like structures in which water flows. The hole in the shell from which the siphon protrudes has a unique keyhole shape.

Ecological Notes The razor clam is well adapted for living in soft tidal substrates. Because of its short siphons, it burrows just below the surface to feed. When the tide goes out, it is strong enough to burrow quickly into deeper sand. The foot of the razor clam is larger and more agile than that of other clams. To burrow, the razor clam pushes its narrow foot down deep into the substrate, then expands the foot as an anchor and pulls the body and shell deeper into the sand. The razor clam is highly sensitive to vibrations and can sense the approach of a nearby predator. Its strong muscular foot enables it to propel itself out of its burrow to escape an attack from below or to burrow quickly if a predator is attacking from above. Clam worms and moon snails prey on razor clams.

Personal Information I encountered this Atlantic jackknife on a Marine Biology class trip to the Outer Banks. The clam immediately caught my eye because it was one of the marine species we covered in class. This Atlantic Jackknife was specifically found on the beach of Cape Hatteras which is located in Nags Head, North Carolina. The clam was found alongside a variety of other Atlantic jackknife clams and mollusc species.

Journal Articles http://www.edc.uri.edu/restoration/html/gallery/invert/razor.htm

Contributed by Allison Tupps - 2018

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