Identification and characterization of microsatellite loci in the rush Juncus effusus (Juncaceae) 1

• Premise of the study: Microsatellite markers were developed for the common wetland plant Juncus effusus to assess levels of within‐ and among‐population genetic diversity. • Methods and Results: Using a next‐generation sequencing approach we identified new microsatellite loci, from which 23 were further characterized in a large population of J . effusus . Expected heterozygosity ranged from 0 to 0.64 with a mean of 0.407. Inbreeding coefficients (mean = 0.984) were very high, confirming earlier suggestions of an inbred mating system. Cross‐amplification was tested in J. conglomeratus , J . inflexus , J . drummondii , and J . filiformis , with best results in the former. • Conclusions: The described microsatellite markers will be helpful in assisting studies on, e.g., reproduction, taxonomy, and phylogeography in J . effusus and related species.