Résumé
The host race of Ceutorhynchus assimilis Paykull, 1792 (Coleoptera: Curculionidae) that specifically develops on Lepidium draba Linn,, 1753 (Brassicales: Brassicaceae), an invasive weed in North America, is being considered for use as a biocontrol agent. Above all, establishing the potential for gene flow between this host race and the other entities within C. assimilis, some of which are pests, is crucial to resolving its taxonomic status, and will ultimately determine if a biocontrol program utilizing this agent can be pursued. Among the 92 microsatellite loci isolated from the C. assimilis genome using 454 pyrosequencing, 31 were retained based upon consistent amplification. Eleven loci exhibited polymorphism in populations sampled in France and Spain. In those populations, the number of alleles per locus ranged from 1 to 7, and the observed and expected heterozygosities ranged from 0.000 to 0.870 and 0.000 to 0.777, respectively. Principal coordinates analysis clearly separated the two populations. These polymorphic loci are the first microsatellites developed in C. assimilis, and represent the most informative markers available for fine- and large-scale population-genetic studies to date.