Male. This is the most abundant crab in the Gambia. Tanji Lagoon, Tanji Bird Reserve. The Gambia.
Ghost Crab? Fiddler Crab? Ocypodidae, in any case. The guide called them Ghost Crabs (Ocypode quadrata), but the claw size looks more like the Fiddler Crab (Uca pugilator) pics I'm seeing. Exposed around Red Mangrove roots at low tide. Didn't see these until a guide pointed them out -- the only visible part was that they they were waving their light-colored claws back and forth.
based on this and other sources regarding the local Fiddler species ... also habitat
Abundant in hundreds from salt marsh down to intertidal zone. In HK also known as the Watermelon Fiddler Crab.
Found sound side of Bear Island, NC in Hammocks Beach State Park. Thousands of them were spotted!
Un cangrejito "manglanero" (Manglares en Alvarádo, Veracruz)
A fiddler crab, sometimes known as a calling crab, may be any of approximately 100 species of semi-terrestrial marine crabs which make up the genus Uca. As members of the family Ocypodidae, fiddler crabs are most closely related to the ghost crabs of the genus Ocypode. This entire group is composed of small crabs – the largest being slightly over two inches across. Fiddler crabs are found along sea beaches and brackish inter-tidal mud flats, lagoons...