Bacterial endophytes colonize the inner tissues of host plants through the roots or through discontinuities on the plant surface, including wounds and stomata. Little is known regarding a possible role of insects in acquiring and transmitting non-phytopathogenic microorganisms from plant to plant, especially those endophytes that are beneficial symbionts providing plant protection properties and homeostatic stability to the host. To understand the ecological role of insects in the transmission of endophytic bacteria, we used freshly hatched nymphs of the American sap-feeding leafhopper Scaphoideus titanus (vector) to transfer microorganisms across grapevine plants. After contact with the vector, sink plants were colonized by a complex endophytic community dominated by Proteobacteria, highly similar to that present in source plants. A similar bacterial community, but with a higher ratio of Firmicutes, was found on S. titanus. Insects feeding only on sink plants transferred an entirely different bacterial community dominated by Actinobacteria, where Mycobacterium sp., played a major role. Despite the fact that insects dwelled mostly on plant stems, the bacterial communities in plant roots resembled more closely those inside and on insects, when compared to those of above-ground plant organs. We prove here the potential of insect vectors to transfer entire endophytic bacterial communities between plants. We also describe the role of plants and bacterial endophytes in establishing microbial communities in plant-feeding insects.

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Since it is not possible, after several years of research, to locate the type material of Chelidura aptera (Megerle in Charpentier, 1825), type species of the genus Chelidura latreille, 1825, and not being able to define in any way, even vaguely, the terra typica, it was decided to fix a neotype. This neotype is here selected on the basis of its matching with the original description and with the support of molecular data. Three Alpine populations, two Italian and one Swiss, of what is actually considered C. aptera were sampled and sequenced; COI sequences were then compared with Chelidura pyrenaica arverna David & Van Herrewege, 1973 from the Massif Central in France, and other species of the genera Chelidurella, Mesochelidura and Forficula. The separation between C. aptera and C. pyrenaica is strongly supported by DNA barcodes and substantial differences among the three Alpine populations have been detected. The genetically intermediate among the Alpine populations (Italy, Piedmont (Biella), Pennine Alps, lago del Mucrone) is chosen as neotype of Chelidura aptera, furthermore largely matching the original description. Further genetic and morphological investigations will clarify the relations among the Alpine populations and in the early future we expect to extend the analyzes to the majority of the Alpine and non-Alpine populations of Chelidura. In addition, the updated view about the taxonomy and distribution of Chelidura and the first illustration of male genitalia of Chelidura pyrenaica arverna David & Van Herrewege, 1973 are provided.

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Drosophila suzukii (Matsumura; Diptera: Drosophilidae) is a key pest of sweet cherry and small fruits worldwide. Biological control remains unutilized in the framework of D. suzukii management. Nonetheless, natural enemies may play an important role in regulating this pest. We report for the first time the presence of Leptopilina japonica Novković and Kimura (Hymenoptera: Figitidae) in Europe. Two specimens emerged from ripened fruits and one was collected after direct observation on a cherry tree in June 2019. They showed the distinctive morphological traits already described and shared more than 99% sequence similarity with specimens of L. japonica collected in Asia. This first finding was confirmed by a wider survey carried out in 2020; L. japonica emerged from cherry fruit samples collected in five other sites across the Trentino region, suggesting that L. japonica has already colonized a wide area. Detection of this Asian species is relevant to the future direction in managing D. suzukii, both in Europe and North America. In fact, L. japonica showed similarity with Ganaspis brasiliensis (Ihering) (Hymenoptera: Figitidae), the most promising candidate for the classical biological control, in terms of developmental time, egg maturation, host age preference and lifetime fecundity.