Discovery of novel NGS-mined microsatellite markers and an exploratory analysis of genetic differentiation between two Western Atlantic populations of Cardisoma guanhumi Latreille, 1825 (Decapoda: Brachyura: Gecarcinidae)

The blue land crab Cardisoma guanhumi Latreille, 1825 is a highly valued food resource widespread in tropical and subtropical regions of the west Atlantic region. Current overharvesting, however, has played a significant role in stock decline. We describe the development of 12 new microsatellite markers, by next-generation sequencing, for evaluating genetic diversity and population structure across the geographical range of the species. A glimpse into the genetic variation in the Caribbean is also provided. The highly informative nature of these markers was also given by the mean estimate values for allelic richness (A_R), gene diversity, and polymorphic information content (PIC); 3.8, 0.593, 0.518 in Florida and 2.9, 0.450, 0.385 in Puerto Rico. A preliminary genetic diversity analysis revealed high population differentiation between both locations (F_ST = 0.310 and D_EST = 0.526). PCoA and Bayesian clustering provisionally detected two genetically distinct groups based on the two predefined populations from the Caribbean.