Crab
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen), usually hidden entirely under the thorax (brachyura means "short tail" in Greek). They live in all the world's oceans, in freshwater, and on land, are generally covered with a thick exoskeleton, and have a single pair of pincers on each arm. They first appeared during the Jurassic Period.
| Crab Temporal range: | |
|---|---|
| Top row, left to right: Dromia personata (Dromiidae), Dungeness crab (Cancridae), Tasmanian giant crab (Menippidae); Middle row: Corystes cassivelaunus (Corystidae), Liocarcinus vernalis (Portunidae), Carpilius maculatus (Carpiliidae); Bottom row: Gecarcinus quadratus (Gecarcinidae), Grapsus grapsus (Grapsidae), Ocypode ceratophthalmus (Ocypodidae). | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Malacostraca |
| Order: | Decapoda |
| Suborder: | Pleocyemata |
| (unranked): | Reptantia |
| Infraorder: | Brachyura Linnaeus, 1758 |
| Sections and subsections | |
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