Ghost crab
A fast-running shore crab in the genus Ocypode, adapted to sandy beaches. Most species are nocturnal and shelter in burrows above the waterline.
Ocypode: A genus of swift, semi-terrestrial crabs that inhabit tropical and subtropical sandy shores. Ghost crabs are species of this genus, whose traits define the group.
Crab locomotion: Movement by crabs using their jointed walking legs, often with sideways or rapid running. Ghost crabs use rapid leg movements to cross broad stretches of exposed beach.
Beach monitoring: The systematic measurement of physical or ecological conditions on beaches over time. Ghost crab burrows and activity can provide field measures of beach habitat condition.
Atlantic ghost crab: Ocypode quadrata, a ghost crab found on Atlantic and Gulf coasts of the Americas. This familiar western Atlantic species illustrates the genus's beach-running and burrowing habits.
Fiddler crab: A small intertidal crab in which males typically have one greatly enlarged claw. Fiddler crabs forage on tidal flats, unlike ghost crabs adapted to dry sandy beaches.
Decapoda: An order of crustaceans with five pairs of walking legs, including crabs, lobsters, and shrimp. Ghost crabs belong to this larger group of ten-legged crustaceans.
Compound eye: An eye built from many visual units, each sampling light from a small part of the surroundings. Raised eyes give ghost crabs a wide view while much of the body stays near the sand.
Coastal ecology: The study of organisms and ecological processes in coastal environments. Ghost crabs are prominent predators and scavengers in sandy-shore food webs.
Pacific ghost crab: Ocypode occidentalis, a ghost crab native to the eastern Pacific coast of the Americas. Its distribution provides a Pacific counterpart to the Atlantic ghost crab.
Sand bubbler crab: A small crab that feeds on organic material in sand and leaves distinctive pellets as the tide recedes. Its feeding pattern and tidal-flat habitat differ from the fast, predatory ghost crab.