This is the first of a three volumes field guide that covers the species of interest to fisheries of the major marine resources groups exploited in the Western Central Atlantic. The area of coverage includes FAO Fishing Area 31. The marine resources groups included in this volume are the bivalves, gastropods, cephalopods stomatopods, shrimps, lobsters, crabs, hagfishes, sharks, batoid fishes and chimaeras. The introductory chapter outlines the environmental, ecological and biogeographical factor s influencing the marine biota and the basic components of the fisheries in the Western Central Atlantic. See also other volumes related to this series: