Insects are known to rely on microbial protection during immobile developmental stages, such as eggs. But despite the susceptibility of pupae to antagonistic challenges, the role of microbes in ensuring defense during an insect’s metamorphosis remained an open question. Scientists from Germany and Panama have now discovered a novel defensive partnership between a fungus and a leaf beetle. The microbe provides a protective layer around the beetle´s pupae and thus prevents predation. In exchange, the beetle disperses the fungus to its host plant, expanding its range. Now published in Current Biology, the researchers present the results of their study.