Image: Scleractinian coral, Thecosmilia trichotoma
Scleractinian coral, Thecosmilia trichotoma, based on fossil from France. Middle Jurassic, 170 million years ago.
- Anne Musser
- © Australian Museum
Scleractinian corals appeared in the Middle Triassic and are the ancestors of modern corals. This species was a colonial coral made up of a number of polyps.