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Here is a smaller version of the clam identification key. This brief key is ideal to help you identify clams that you may find on the beaches of Puget Sound. You can print this key directly from this page (use print command in program menu) or you can contact Bob Brenner for a copy of this key. Happy Clamming!

Can you see a leathery hinge connecting the shells?

  1. NO

    1. Shells are mirror images of each other, flaps are present on the tips of siphons. It is a Horse Clam.

      horse clam

    2. Shells are not mirror images, no flaps are present on the tips of siphons. It is a Softshell Clam.

      softshell clam

  2. YES

    1. Rings or ribs are easily seen on the shells.

      • Shell has heavy ribs, shell is heart-shaped. It is a Cockle.


      • Rings and ribs are equally visible.

        • Shell is elongated, there is a flat pit near the umbo. It is a Manila Clam.

          manila clam

        • Shell is rounded, there is no pit near the umbo. It is a Littleneck Clam.

          littleneck clam

    2. Faint rings or ribs are seen on the shells.
      • Shells are rounded on both ends, no periostracum. It is a Butter Clam.

        butter clam

      • Shells are pointed somewhat on one end, band of periostracum is seen along shell edges. It is a Sand Clam.

        sand macoma

Back to Clam Identification Key

Updated: 11/01/98

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