giant clam

mollusk

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June 29, 2026

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A giant clam is a very large clam, specifically Tridacna gigas, found on coral reefs in the Indian and Pacific oceans. These mollusks can weigh over 500 pounds (227 kilograms). Unlike many other bivalves that filter feed on detritus, algae, or bacteria, giant clams have a symbiotic relationship with zooxanthellae, which are minute algal cells living within their mantle tissue. This relationship is likely mutually beneficial, providing the clam with nutrition and the algae with a protected environment and access to the clam's waste products. The size of clams varies greatly, with the giant clam being the largest at up to 1.2 meters across.123

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bivalve
Food and feeding
…the shipworms (family Teredinidae) and giant clams (family Tridacnidae). Shipworms are wood borers and are both protected and nourished by the wood they inhabit. They possess ctenidia and are capable of filtering food from the sea. When elongating the burrow, they digest the wood as well. In the Tridacnidae, symbiotic…
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…the shipworms (family Teredinidae) and giant clams (family Tridacnidae). Shipworms are wood borers and are both protected and nourished by the wood they inhabit. They possess ctenidia and are capable of filtering food from the sea. When elongating the burrow, they digest the wood as well. In the Tridacnidae, symbiotic…
Read More