Science: How Many Legs Does a Crab Have?

Crabs are crustaceans with eight walking legs and two legs that are sometimes used for walking but usually used for eating. These are its pincers and they are called chela. The front two legs are called chelipeds.

  1. Crabs in Motion

    • Some crabs live on land while others live underwater. Those that live underwater have paddles on their back legs that allow them to swim. Crabs that live primarily on land walk sideways; the legs on one side of the body pull while the others push, propelling the crab sideways.

    Decapods

    • Crabs are crustaceans, but they are also decapods meaning that they have 10 legs. Decapods are a type of crustacean that includes lobsters and shrimp.

    Types

    • There are more than 45,000 species of crabs. Crabs can live in salt- or freshwater depending on the species. Some species of crabs live at the mouths of rivers, while others live on rocky and sandy beaches. They may also live in coral reefs or in subtidal zones where they are always completely submerged.