Evidence of Actual Copulation in the Burrow in the Fiddler Crab, Uca Lactea (De Haan, 1835) (Decapoda, Brachyura, Ocypodidae)

A total of 205 Uca lactea females, which were reared in the laboratory for more than two months without the presence of males, were used to determine if crabs copulate in males' burrows. The females were released in the field and were enticed by courting males into their burrows. Pairs in the burrows were caught after 24 minutes or more. The occurrence of copulation in males' burrows was proven by the presence of spermatophores in the vagina. About 60% of the females were inseminated two hours after staying in males' burrows.