? Malacostraca | ||||||||
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| [image] Eophreatoicus (a fresh water isopod from Australia) | ||||||||
| Scientific classification | ||||||||
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| Orders | ||||||||
| Subclass Eumalacostraca Superorder Eucarida Order Amphionidacea Order Decapoda - crabs, shrimp Order Euphausiacea - krill †Superorder Pancarida †Order Thermosbaenacea Superorder Peracarida Order Amphipoda - amphipods Order Cumacea - cumaceans Order Isopoda - pillbugs, sowbugs Order Lophogastrida Order Mictacea Order Mysida †Order Spelaeogriphacea Order Tanaidacea Superorder Syncarida Order Anaspidacea Order Bathynellacea †Order Palaeocaridacea Order Stygocaridacea Subclass Hoplocarida Order Stomatopoda - mantis shrimp Subclass Phyllocarida †Order Archaeostraca †Order Hoplostraca Order Leptostraca |
The Malacostraca are the largest subgroup of crustaceans and include most of the animals that non-experts recognise as crustaceans, such as the decapods (such as crabs, mole crabs, lobsters and true shrimps), the stomatopods or mantis shrimps, and krills. They also include the huge group of amphipods, and the only substantial group of land-based crustaceans, the isopods (woodlice or sowbugs and related species). With more than 22'000 members, this group represents two third of all crustacean Species and contains all the larger forms. It first appeared in the Cambrian.
The classification of crustaceans is currently being debated, and the Malacostraca are regarded by some authors as a class and by others as a Subclass.