Invertebrates lack backbones. Some familiar invertebrate groups are sponges, jellyfish, corals, worms, clams, snails, octopuses and squids, spiders, scorpions, insects, crabs and lobsters, shrimp, starfish, and sea urchins.
Because of their lower position in the food chain, invertebrates are of great importance in the diets of many Everglades predators, including fishes, amphibians, young alligators and crocodiles, wading birds, otters, and many others.
Most marine invertebrates have planktonic larval forms that are dispersed by ocean currents. Not all southern Florida marine invertebrates are strictly tropical, and some are dependent on estuaries for part of their life cycle. Three commercially important examples are the blue crab, pink shrimp, and eastern oyster.