Because of the potential impact of bacterial symbionts on the adaptation of hemipteran insects to plant hosts, we characterized the microbial community present in various populations of H. obsoletus by pyrosequencing. Analysis of the V4V5 variable region of the 16S rDNA showed that insects sampled on Lavandula and Salvia possessed a bacterial sequence 100 % identical to the 16S rDNA of an endosymbiont of Irenimus aequalis. As shown by the two mtDNA markers 16S rRNA-tRNALeu-ND1 and COI-tRNALeu-COII, Hyalesthes specimen from Lavandula were genetically different from those of Salvia as it was the case between specimen from Urtica compared to specimen from Convolvulus. Insects sampled from Lavandula and Salvia were also significantly smaller than those sampled from Urtica and Convolvulus.