Seven polymorphic microsatellite loci were developed for the planthopper Hyalesthes obsoletus, vector of stolbur 16SrXII-A phytoplasma. The loci have di- or trinucleotide repeat motifs and are highly variable with 10 to 22 alleles per locus. Observed heterozygosity ranged from 0.278 to 0.950 for the 78 individuals genotyped. One locus is sex-linked. No linkage between loci was found. All loci amplified consistently among phylogeographic as well as host-plant related samples and proved highly informative for population genetic studies. and Miriam IMO, Julia LÜNEBURG, Thomas HANKELN, Alfred SEITZ, Jes JOHANNESEN.