Fauna
Invertebrate

Noah's Giant Clam

Tridacna noae

Also known as Teardrop Giant Clam, Noah's Clam

Noah's giant clams showcase stunning, vibrant mantles adorned with distinctive teardrop-shaped spots outlined in gold or white. These marine bivalves anchor themselves securely to shallow coral reefs, where they expose their colorful tissues to the sun to nourish their symbiotic algae. While long mistaken for the small giant clam, they are distinguished by their unique mantle patterns and discrete genetic lineage.

MarineReef DwellerSymbiotic
Noah's Giant Clam reference
iNaturalist user: thibaudaronson / CC BY-SA 4.0 · cc-by-sa
—observations
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Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Key facts
Diet & preyMicroalgae, Plankton, Dissolved organic matter
Predators
  • Triggerfish
  • Octopuses
  • Crabs
ThreatsOverharvesting for the aquarium trade, habitat degradation, and ocean warming
HabitatsShallow coral reefs, lagoons, and reef flats
Life spanUp to 50 to 100 years
Classification
  1. FamilyCardiidae
  2. SpeciesTridacna noae
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
What to notice
Look for the distinctive teardrop-shaped spots ringed with white on its colorful mantle.
Support conservation
Never touch, step on, or attempt to pry the clam from its coral substrate.
Responsible observation
  • Do not touch: Avoid touching the sensitive mantle tissue, which causes the clam to snap shut.
  • Maintain distance: Keep a respectful distance while snorkeling to prevent casting a shadow that triggers defensive retraction.
Related species
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