zooxanthellae
/ˌzoʊzænˈθɛli/
noun
- Tiny algae that live inside the tissues of corals and some other marine animals, providing them with food and color through photosynthesis.
- The bright colors of many sea anemones come from the zooxanthellae living inside them.
- When water gets too warm, corals expel their zooxanthellae and turn white, a process called bleaching.
- Coral reefs depend on zooxanthellae for most of their energy.