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A large pink sea anemone surrounded by coral and small orange fish.
Photo: Nhobgood Nick Hobgood, CC BY-SA 3.0, via Wikimedia Commons

Corals and Sea Anemones

Class Anthozoa

Stinging, flower-like sea animals; reef-building corals create giant structures like the Great Barrier Reef.

🐛 Invertebrates
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About the Corals and Sea Anemones

Corals and sea anemones belong to a group called Anthozoa. Like jellies, they are cnidarians, which means 'stinging needles,' and they have stinging cells. Their bodies are arranged in a circle around a central mouth. They live from shallow shores to deep ocean trenches, but reef-building corals live only in shallow tropical and subtropical waters. Many corals get food from tiny algae living inside them.[1]

Quick facts

Scientific name
Class Anthozoa[1]
Diet
Food from algae living inside them, plus plankton and small animals caught with stinging cells.[1]
Habitat
Oceans, from shallow shores to deep trenches; reefs in shallow tropical seas.[1]
Where it lives
Oceans worldwide, most in warm tropical waters.[1]
Group life
Corals often live in colonies of many polyps.[1]
Babies
New corals grow by budding, from broken pieces or from eggs.[1]
Conservation status
Varies by species. Coral reefs are threatened by disease, climate change, overfishing and pollution.[1]

Fun facts

  • Some coral reefs began growing 50 million years ago.[1]
  • A coral colony can have hundreds of thousands of polyps.[1]
  • Cnidarian means 'stinging needles.'[1]

Vocabulary

polyp
A small, tube-shaped animal with tentacles around its mouth.
coral reef
A huge structure built by colonies of tiny coral animals.
cnidarian
An animal with stinging cells, such as a coral, anemone or jelly.
symbiosis
A close relationship between two different kinds of living things that often helps both.
invertebrate
An animal without a backbone.

See it in person

These zoos had this animal when we gathered our information, but animals sometimes move. Check the zoo's website or contact the zoo before you visit.

Sources

  1. [1] Smithsonian's National Zoo & Conservation Biology Institute. “Corals and sea anemones (Anthozoa).” https://nationalzoo.si.edu/animals/corals-and-sea-anemones-anthozoa (accessed 2026-10-08)

Facts last checked 2026-10-08.

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