Crustacea Fossil range: Cambrian to present
Abludomelita obtusata, an amphipod
Scientific classification
Included groups
Thylacocephala? † Branchiopoda Phyllopoda Sarsostraca Remipedia Cephalocarida Maxillopoda Thecostraca Tantulocarida Branchiura Pentastomida Mystacocarida Copepoda Ostracoda Myodocopa Podocopa Malacostraca Phyllocarida Hoplocarida Eumalacostraca
Cladistically included but traditionally excluded groups
Hexapods

American lobster

Edible shrimp

Crustaceans are a subphylum of arthropods with 67,000 described species. They are part of the phylum Arthropoda. Crustaceans include crabs, lobsters, crayfish, shrimp, krill and barnacles. They are relatives of insects. If the Arthropods are regarded as a superphylum, then the insects and crustacea would be phyla (see List of animal phyla). The group has an extensive fossil record, reaching back to the Cambrian.