Eucarida is a superorder of crustaceans, comprising the decapods, krill and Amphionides. Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Bilateria  Acoelomorpha  Orthonectida  Rhombozoa  Myxozoa  Superphylum Deuterostomia     Chordata (vertebrates, etc. ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - Trilobites (extinct) Subphylum Chelicerata Arachnida - Spiders, Scorpions, etc. ... Classes Remipedia Cephalocarida Branchiopoda Ostracoda Maxillopoda Malacostraca The crustaceans (Crustacea) are a large group of arthropods (55,000 species), usually treated as a subphylum. ... Orders Not necessarily a complete list: Leptostraca Stomatopoda Bathynellacea Thermosbaenacea Mysidacea Cumacea Amphipoda Isopoda Tanaidacea Euphausiacea Amphionidacea Decapoda Peracarida The Malacostraca are the largest subgroup of crustaceans, and include most of the animals that non-experts recognise as crustaceans, including the decapods (such as crabs, mole crabs, lobsters and true... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Suborders Either suborders: Natantia Reptantia or suborders: Dendrobranchiata Pleocyemata The decapods or Decapoda are a group of crustaceans within the class Malacostraca. ... Common name. ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Classes Remipedia Cephalocarida Branchiopoda Ostracoda Maxillopoda Malacostraca The crustaceans (Crustacea) are a large group of arthropods (55,000 species), usually treated as a subphylum. ... Suborders Either suborders: Natantia Reptantia or suborders: Dendrobranchiata Pleocyemata The decapods or Decapoda are a group of crustaceans within the class Malacostraca. ... Euphausiid is the scientific name for shrimp-like marine invertebrates, important organisms of the plankton (zooplankton), also called krill. ...