Assessing the Genetic Diversity and Gene Flow of Populations of the Crab Ucides Cordatus (Decapoda: Ocypodidae) on the Brazilian Coast Using Microsatellite Markers

The variation in five microsatellite loci was used to estimate the genetic structure and demographic parameters of the mangrove crab, Ucides cordatus (Linnaeus, 1763), based on 365 individuals from nine locations throughout the Brazilian coast. There was considerable variability in the studied fragments, with high values of expected heterozygosity and evidence for weak genetic structure between some of the samples and regions, despite vast geographical distances between then. FST values involving the Amapa sample were near zero, indicating that the estuary of the Rio Amazonas mouth does not represent a barrier to dispersal of this species. However, the highest levels of genetic divergence involve the southernmost sample (Parana, FST=0.03).