Ivory tree corals
The ivory tree coral, Oculina varicosa, builds extensive reefs similar in size, shape and structure to Lophelia. In contrast to the broad geographic range of Lophelia, however, these reefs are found only off the southeastern US.
Oculina is unusual because it adapts to the long term presence or absence of light. In shallow waters, it possesses the algae needed to help it use energy from the sun, much like other tropical corals; in deep water it feeds from the surrounding water. The deep sea form is found from 160 to 500 feet deep on the edge of the continental shelf from North Carolina to Florida, although most deep-sea Oculina grow in individual bushes and do not create reefs.
The only known Oculina reefs, known as the Oculina Banks, stretch 100 miles along the central eastern Florida shelf edge at a depth of 230 to 330 feet. The Oculina Banks have an exceedingly high diversity of fish, shellfish, starfish, sponges and other animals, similar to that of tropical coral reefs.
This dense and diverse community supports large numbers of fish, forming breeding grounds for gag and scamp grouper, nursery grounds for young snowy grouper and feeding grounds for many other economically valuable fish including bass, other groupers, jacks, snappers, porgies and sharks.