Population discrimination of the French grunt, Haemulon flavolineatum (Desmarest, 1823) between the Campeche Bank and the Mexican Caribbean Sea, inferred by microsatellite loci

Abstract

Genetic structure of the French grunt Haemulon flavolineatum, population was determined in four localities, two located in the Campeche Bank (Cayo Arcas and Alacranes) and two in the Mexican Caribbean (Puerto Morelos and Banco Chinchorro) using microsatellite loci. Intra- and inter-population genetic variabilities, and genetic distances were evaluated. The Monmonier’s maximum-difference algorithm was used to identify population structure and the putative genetic barriers across the oceanographic landscape. Overall expected heterozygosity (He) was lower (0.81) than the observed heterozygosity (Ho = 0.85). Inbreeding index indicated an excess of heterozygotes occur within the whole study area (FIS = -0.039); while fixation index denoted genetic significant differences between localities (FST = 0.033). Nei’s genetic distances were wider between Puerto Morelos and Alacranes (0.232), while the narrower were observed between Alacranes and Cayo Arcas (0.106). Monmonier’s algorithm revealed three putative barriers: the first one separated the Campeche Bank from the Caribbean, the second one separated Puerto Morelos from Chinchorro, and finally the third one separated Cayo Arcas from Alacranes. Regional currents allow dispersion of H. flavolineatum between distant populations of the Mesoamerican Barrier Reef and the Gulf of Mexico, but they are not enough to homogenize the populations to form a panmictic population.