Malacostraca

Malacostraca is the largest class of crustaceans, including crabs, lobsters, shrimp, krill, and woodlice. Most have a head, an eight-segmented thorax, and a six-segmented abdomen.

Crustacea: A diverse group of arthropods that includes crabs, insects’ aquatic relatives, and many other animals. Malacostraca is the largest class within this broader crustacean group.
Ecdysis: The shedding of an animal’s outer covering to allow growth or developmental change. Malacostracans must molt their exoskeletons as they grow.
Krill: Small, shrimp-like marine crustaceans that form dense swarms and feed largely on plankton. Krill are pelagic malacostracans that support major ocean food webs.
Amphipoda: An order of laterally compressed crustaceans that includes sand hoppers and scuds. Amphipods are one of the major malacostracan groups outside the familiar decapods.
Crustacean fisheries: The commercial and subsistence harvesting of crustaceans for food and other products. Many fisheries target malacostracans such as crabs, lobsters, and shrimp.
Arthropod: An invertebrate animal with a segmented body, jointed limbs, and an external skeleton. Malacostracans share the defining body plan of arthropods.
Crustacean larva: An immature crustacean stage that differs in form from the adult. Many malacostracans pass through distinctive larval stages before reaching adult form.
Woodlouse: A terrestrial isopod crustacean that typically lives in damp places and feeds on decaying matter. Woodlice demonstrate that malacostracans include animals adapted to life on land.
Euphausiacea: An order of pelagic crustaceans that includes krill. Its members are a distinct malacostracan lineage with major ecological importance.
Shrimp aquaculture: The farming of shrimp in controlled ponds, tanks, or coastal enclosures. Farmed shrimp are malacostracans and a major component of global aquaculture.

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