Crustaceans

Crabs, lobsters, prawns and other crustaceans

Crustaceans are among the most widespread and diverse group of invertebrates. They can be found in a variety of environments, on land or in the sea. Although originally aquatic, many crustaceans, such as slaters and beachhoppers, are 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 they are extremely varied, all crustaceans have a body divided into a head, thorax and abdomen, two eyes and two pairs of antennae, a hard exoskeleton and jointed, paired appendages.

Crustaceans have an abundant fossil record, with species like the mantis shrimp being a living fossil which has existed unchanged since the Miocene age. Living fossils are animals which show little to no morphological variation from early ancestors of the same lineage over long periods of time.

Learn more about the wonderful crustaceans in the Australian Museum collection factsheets below.