Cellular Localization of Two Symbionts in the Digestive System and within the Ovaries of the Mirid Bug, .

Bacterial symbionts in arthropods are common, vary in their effects, and can dramatically influence the outcome of biological control efforts. (Heteroptera: Miridae), a key component of biological control programs, is mainly predaceous but may also display phytophagy. hosts symbiotic , which induce cytoplasmic incompatibility, and two species, and , which are found in all individuals tested. To test possible involvement of the two species in the feeding habits of , we first showed that the microbiome of the insect is dominated by these three symbionts, and later described the distribution pattern of the two species in its digestive system. Although both species were located in certain gut bacteriocyes, in caeca and in Malpighian tubules of both sexes, each species has a unique cellular occupancy pattern and specific distribution along digestive system compartments. Infrequently, both species were found in a cell. In females, both species were detected in the germarium, the apical end of the ovarioles within the ovaries, but not in oocytes. Although the cause for these distribution patterns is yet unknown, it is likely linked to host nutrition while feeding on prey or plants.