Blue Clam Mantle - Great Barrier Reef, 2001
The mantle or soft tissue of a giant clam faces upward between the scalloped sides of the shell which are grounded in the sand or reef. I've seen giant clams over 5 feet in length. I assume they close their shells at night, but during the day they expose their often beautiful and colorful mantles. See also "Blue Lips" Clam Mantle and Gold Clam Mantle.
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