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* Premise of the study: Whereas population genetic studies have examined allopolyploids. comparable studies of naturally occurring autopolyploids remain rare. To address fundamental questions regarding autopolyploidy. we undertook a detailed population genetic study of one of the classic examples of autopolyploidy, Galax urceolata (Diapensiaceae), which comprises diploid. triploid, and autotetraploid cytotypes. Galax is endemic to the Appalachian Mountains, the adjacent piedmont, sandhills, and coastal plain and represents perhaps the most widely known example of autopolyploidy in nature. * Methods: Flow cytometry was used to diagnose ploidal level of -1000 individuals across 71 populations. We used 10 microsatellite markers to examine genetic variation across the geographic range of Galax and assessed multiple origins though comparisons of diploid, triploid, and letraploid accessions using multiple analytical approaches. * Key results: Tetraploids had higher levels of heterozygosity than diploids did. Genetic variation in diploid and tetraploid Galax is geographically structured among the ecoregions of the southeastern United States. Autotetraploidy in Galax urceolata has occurred independently at least 46 times, with triploidy having occurred a minimum of 31 times. * Conclusions: Genetic differentiation among ecoregions suggests historical patterns of local adaptation. The numerous independent origins of tetraploid Galax reported here are among the highest frequencies of independent polyploidizations ever reported for any polyploid (auto- or allopolyploid). [ABSTRACT FROM AUTHOR]

• Premise of the study: Microsatellite markers were developed for Galax urceolata to investigate genetic diversity, population structure, and polyploid origins (auto- vs. allopolyploid), and to estimate the minimum number of independent cytotype origins. • Methods and Results: Ten primer sets have been developed, and preliminary study indicates that all loci are appropriate for population-level genetic investigations. All loci are polymorphic with 6 to 46 alleles per locus. Expected heterozygosity ranges from 0.1007 to 0.6085. • Conclusions: The microsatellite markers presented will facilitate analyses of polyploid origins, genetic diversity, geographic structure, and gene flow. [ABSTRACT FROM AUTHOR]