Eucarida is a of crustaceans, comprising the decapods, krill and Amphionides. They are characterised by having the carapace fused to all thoracic segments, and by the possession of stalked eyes.
The Superorder Eucarida is further organized into finer groupings including:
Amphionides reynaudii is the sole representative of the Amphionidacea, and is a small (less than one inch long) planktonic crustacean found throughout the world's tropical oceans, mostly in shallow waters. Morphologically, Amphionides is somewhat unusual, with many body parts being reduced or absent. For example, it has only one pair of mouthparts — the maxillae — the mandibles and maxillules being absent. [more]
The decapods or Decapoda (literally means "ten footed") are an order of within the class Malacostraca, including many familiar groups, such as crayfish, crabs, lobsters, prawns and shrimp. Most decapods are scavengers. [more]
Krill are a type of -like marine invertebrate animal. These small crustaceans are important organisms of the zooplankton, particularly as food for baleen whales, manta rays, whale sharks, crabeater seals, and other seals, and a few seabird species that feed almost exclusively on them. Another name is euphausiids, after their taxonomic order Euphausiacea. The name krill comes from the Norwegian word krill meaning "young fry of fish," which is also often attributed to other species of fish. [more]
At least 117 species and subspecies belong to the Order Euphausiacea.
More info about the Order Euphausiacea may be found here.
