Ocypodidae

Ocypodidae is a family of semiterrestrial crabs, commonly known as ghost crabs and fiddler crabs. These crabs are found in tropical and subtropical regions worldwide, inhabiting sandy beaches, intertidal zones, and mangrove swamps. The family is characterized by several distinct features, including their large eyes that are often on stalks and their ability to breathe air.

Ghost crabs, belonging to the genus Ocypode, are known for their pale coloration, which allows them to blend in with the sand, and their rapid movement. They are primarily nocturnal predators, feeding on small invertebrates and carrion. Fiddler crabs, in contrast, are distinguished by the extreme sexual dimorphism in their claws, where males possess one dramatically enlarged claw used for signaling, defense, and fighting. Females have two smaller, equal-sized claws. Fiddler crabs are omnivores and play an important role in aerating the sediment in their habitats.

The family Ocypodidae is divided into several genera, with Ocypode and Uca being the most well-known. Members of this family exhibit a range of behaviors, including complex burrowing activities essential for thermoregulation and protection from predators. Their ecological role is significant in coastal ecosystems, contributing to nutrient cycling and serving as a food source for various predators. The conservation status of some species is a concern due to habitat loss and pollution affecting their coastal environments.