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Crustaceans live deep in the ocean, high on the rocky shore and everywhere in between. Some species are found in fresh water and a few have adapted to life on land.

Crustaceans vary in size from microscopic plankton less than 1 mm long to enormous crabs. Smaller crustaceans such as amphipods, copepods and isopods form the basis of many ocean food chains.

Although crustaceans are extremely varied, they all share the following characteristics:

  • a body divided into a head, thorax and abdomen
  • two eyes and two pairs of antennae
  • a hard exoskeleton
  • jointed, paired appendages (some crustaceans have up to 17 pairs of legs).