Crustacean | 水產百科網

TheCrustaceaareasubphylumofarthropodswith67,000describedspecies.TheyarepartofthephylumArthropoda.Crustaceansincludecrabs,lobsters, ...

The Crustacea 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.

Most crustaceans are aquatic, mostly marine. Some have moved onto land permanently. Crustaceans that live on land include some crabs, and woodlice. Crustacea range in size from a parasite 0.1mm long, to the Japanese spider crab with a leg span of up to 14 ft (4.3 m) and a mass of 44 lb (20 kg). The North Atlantic lobster can weigh more than 40 pounds.

Most crustaceans ...