Discovery and characterization of microsatellites for the solitary bee Colletes inaequalis using Sanger and 454 pyrosequencing

The recent implementation of next-generation sequencing for the discovery of microsatellite markers has made this technology the most effective method for generating genetic markers in non-model organisms. Here, we report the de novo discovery of microsatellite markers for the solitary bee Colletes inaequalis using cloning/Sanger sequencing and direct 454 pyrosequencing from microsatellite-enriched genomic libraries. We identified and successfully multiplexed 18 highly variable microsatellite markers in 585 individuals. The number of alleles per locus ranged from 3 to 23, and the expected heterozygosity ranged from 0.056 to 0.912. These genetic markers will allow for the investigation of levels of inbreeding and fine-scale population structure in C. inaequalis. Our results contribute to the literature demonstrating that 454 sequencing is more time- and cost-efficient than cloning/Sanger sequencing at identifying a large number of genomic regions with microsatellite repeat motifs.