Microsatellite markers for the hybridizing tiger swallowtails, Papilio glaucus and P. canadensis, and their applicability to historic specimens and congeneric species.

We report the development of microsatellite markers for the sister species Papilio glaucus and P. canadensis (Papilionidae: Lepidoptera). All 16 markers displayed a high degree of variation in both species, ranging from eight to 24 alleles per locus. Substantial heterozygote deficits were observed for several loci, indicating the presence of null alleles. All markers were successfully used to genotype dried samples from a historical collection. Cross-species amplification with six additional Papilio species showed that most loci can be used to study genetic variation in other closely related species of tiger swallowtails.