Acropora palmata, or Elkhorn Coral, is considered to be one of the most important reef-building corals in the Caribbean. This species of coral is structurally complex with many large branches that resemble elk antlers and create habitats for many other reef species. Elkhorn coral colonies are fast growing. The color, which ranges from brown to a yellowish-brown, is a result of the symbiotic zooxanthellae that live inside the tissue of this coral species.