Studies on mating patterns of marine crustaceans are rare, but the few studies on brachyuran crabs to date suggest that polyandrous mating is uncommon. In the present study, we used six microsatellite loci to genotype 8-16 larvae obtained from each of 10 gravid females of the crab Ucides cordatus (Brachyura: Ocypodidae). Based on the number of non-maternal alleles detected among the offspring, at least 40% of the females were inseminated by more than one male. We suggest forced copulation and maintenance of sperm in spermathecae throughout the year as possible causes of polyandry in U. cordatus.
- Mating behavior
- Sexual selection