Spatial genetic structure reveals migration directionality in Mediterranean Ruppia spiralis (Western Sicily)

Mediterranean salinas, originally built for salt production, function as alternative wetlands. A variety of accompanying lagoon, ditch, and marsh systems are suitable habitats salt-tolerant submerged macrophytes often characterized by monospecific beds Ruppia . Traditionally, birds considered the main dispersal vector macrophytes. However, spiralis under marine influence therefore interference coastal currents in their connectivity might be expected. In this study, we aim to infer spatial patterns from population genetic structures. Using nuclear microsatellite loci, ribosomal cistron chloroplast sequences, investigated diversity, structure, demographic history 10 R. populations along a 25-km stretch western Sicily encompassing saline habitats. We tested local fine-scaled structures, hypotheses regional isolation distance, migration directionality. Our results revealed high degree allele gene diversity that was locally maintained outcrossing. At level, detected distance identified three genetically differentiated clusters, with significant structure matches an overall north-to-south unidirectional model. This directionality follows sea current, hence indicating importance hydrological conservation management. Significant fine-scale structures only emerged some were absent ‘salina fridda’ habitat showed largest clonal richness. The site-dependent emphasize need examine disturbances on seed recruitment growth over small distances.