Mollusks and Marine Environments of the Ten Thousand Islands provides the first comprehensive overview of the shells and habitats that are present in the last unexplored coastal area of southwestern Florida. The mysterious and primordial Ten Thousand Islands, where the rivers and marshlands of the Everglades empty into the Gulf of Mexico, house a number of remarkable marine ecosystems, many shown here in detail for the first time. Primary among these are unique worm shell “reef systems,” composed entirely of immense masses of vermetid gastropod mollusks. These previously unexplored and unstudied gastropod reefs, which are often many acres in size, are shown here to mimic coral reefs in their growth structure and represent the only large-scale molluscan reefs found anywhere on Earth. Living in association with the zonated gastropod reefs are a number of rare and unusual mollusks, some of which represent endemic species that are unique to the Ten Thousand Islands. These and many other southwestern Florida shells are illustrated throughout this book, along with detailed illustrations and descriptions of the marine and estuarine environments that dominate the archipelago and its adjacent lagoon systems.