Xyleborini is the largest tribe of Scolytinae accounting for about 1300 species worldwide; all species are primarily xylomycetophagous, developing on symbiotic fungi farmed in plant woody tissues. Xyleborini wood-boring action, associated with the inoculum of symbiotic fungi, can lead, sometimes, to the emergence of host plant dieback, wood damage and death; for this reason, multiple Xyleborini are major pests on both cultivated, forest and ornamental trees. Many Xyleborini are invasive worldwide and great effort is expended to manage their biological invasions or prevent new arrivals. Imports of host plants often have a primary role as a pathway for introduction and are frequently responsible for the establishment of species in non-native environments. In this context, data availability on Xyleborini host plants is a major limiting factor in the development of effective detection and monitoring strategies as well as a fundamental variable to consider in risk assessment of plant pests and invasive species. This contribution provides updated host records and the hosts economic categorization for the 1293 Xyleborini known worldwide to date.

Although outbreaks of rare species are unusual, several insect species have become emerging pests probably due to the ongoing environmental changes. Barbitistes vicetinus was first described in 1993 as an endemic bush‐cricket of north‐east Italy and was considered rare until 2008, when it became an established pest, causing severe damages to forests and crops. The possible role of temperature in changing its life cycle has still to be fully understood. Here, we explored the effect of summer temperature on egg diapause and the effect of winter temperature on egg survival. Field observations showed that the proportion of embryos that can complete development at the end of summer ranged from zero to nearly 90% depending on summer temperatures. A substantial shift in the rate of development from 20% to nearly 80% occurred in a thermal range of about 1 °C. On the contrary, overwinter egg survival was high and constant (90%) across a wide range of winter temperatures that go well beyond both the cold and warm thermal limits of the current species range. Overall, the results suggest a potential key role of summer temperature warming on the outbreak propensity of this species that is able to switch from a multiyear to an annual life cycle with just a 1–2 °C warming.

Insect outbreaks usually involve important ecological and economic consequences for agriculture and forestry. The short-winged bush-cricketBarbitistes vicetinusGalvagni & Fontana, 1993 is a recently described species that was considered rare until ten years ago, when unexpected population outbreaks causing severe defoliations across forests and crops were observed in north-eastern Italy. A genetic approach was used to analyse the origin of outbreak populations. The analysis of two mitochondrial regions (Cytochrome Oxidase I and II and 12S rRNA-Control Region) of 130 samples from the two disjunct ranges (Euganean and Berici Hills) showed high values of haplotype diversity and revealed a high geographical structure among populations of the two ranges. The high genetic variability observed supports the native origin of this species. In addition, results suggest that unexpected outbreaks are not a consequence of a single or few pestiferous haplotypes but rather the source of outbreaks are local populations which have experienced an increase in each area. The recent outbreaks have probably appeared independently of the genetic haplotypes whereas environmental conditions could have affected the outbreak populations. These findings contribute to a growing understanding of the status and evolutionary history of the pest that would be useful for developing and implementing biological control strategies for example by maximizing efforts to locate native natural enemies.

Tribes Coriacephilini, Corthylini, Cryphalini, Ernoporini, Trypophloeini, Xyloctonini, and Xyloterini (Coleoptera: Curculionidae; Scolytinae) include spermophagous, phloeophagous, and xylomycetophagous species. Besides direct damage caused by burrowing into host plant tissues, some species are vectors of aggressive pathogens causing plant dieback and death, with consequent economic and ecological relevance. The international trade in plants and wood products is one of the main pathways for the introduction of non-native species worldwide. In this context, data availability on host plants and their economic uses is essential in pest risk assessment and for planning effective detection and monitoring strategies against invasive species. This paper provides a complete and updated list of host plants, with economic categorization, for 2139 scolytine species.

To face recurrent temperature changes, tettigoniids inhabiting temperate climates overwinter as eggs in a diapause stage, being able to postpone embryogenesis for one or more years. To date, it is unclear if species living in warm regions, especially under the Mediterranean climate, could exhibit a diapause for a single year or enter a prolonged diapause due to higher summer temperatures experienced by eggs immediately after oviposition. In this two-year study, we tested the effect of summer temperatures on diapause of six Mediterranean tettigoniid species under natural field conditions. We found that five species can exhibit a facultative diapause depending on mean summer temperatures. For two species, a substantial shift in egg development from 50 to 90% occurred over an interval of c. 1 °C after the first summer period. All the species increased considerably their development (nearly 90%) after the second summer period irrespective of temperatures. Overall, this study suggests that diapause strategy and the different thermal sensibility of embryonic development varies considerably across species potentially affecting their population dynamics.