Coral coasts are found in the southeastern Atlantic from St. Lucie Inlet to Biscayne National Park in Florida. The coral reefs in this area are an extension of the reef tract that surrounds the southern edge of Florida from the Atlantic into the Gulf of Mexico.
Nearshore coral formations include hardbottom areas and patch reefs, which host octocoral, macroalgae, stony coral and sponges. From Martin County to Palm Beach County, Florida, limestone ridges and terraces have been colonized by reef biota. Mid-shelf and shelf margin reefs are located offshore from Palm Beach County to Miami-Dade County.
Worm reefs are also found in the nearshore waters of southeastern Florida. Worm reefs are a type of biogenic reef, not related to coral reefs, that are produced by colonies of tubeworms, Serpulid worms and Sabellariid worms are two types known to form significant reef structures by constructing external tubes in which they live. The Serpulids build their tubes from calcareous secretions and the Saberllariids by cementing particles of sand and shell fragments around their bodies. Colonies of these worms are capable of constructing massive structures by cementing their tubular structures together.