Mole crabs (Emerita talpoida and a number of related species) are clawless oval-shaped crustaceans found on the Atlantic coast of North America. Although like the true crabs they belong to the order Decapoda, they are classified in a different infraorder, Anomura (the true crabs are in the infraorder Brachyura).

Mole crabs live under sand in shallow water near the shore, and live from two to three years. They have the color and texture of rippled sand at the water's edge and live mostly buried in the sand, with their antennae reaching into the water. These antennae filter plankton and organic debris from the water. Mole crabs also eat the tentacles of Portuguese man o' war, which are collected by winding the tentacle around the mole crab's leg. Their camouflage protects them from their predators - chiefly fish and birds.

Females grow to about 35 mm long, and carry their bright orange colored eggs under their telson during the summer months until they are ready to hatch. Males are smaller, only reaching 20 mm, making the sexes easy to tell apart when fully grown.