The spread of Carpophilus truncatus is on the razor's edge between an outbreak and a pest invasion.

In 2019, in southern Italy (Campania) there was an outbreak of a sap beetle infesting stored walnut fruits. A monitoring activity started to assess the spread and impact of the pest in walnut orchards and in warehouses, and an integrative characterization led to identify the beetle as Carpophilus truncatus. This species has been in Europe for a long time, rare and harmless until recently. We show also that this species is the same recently recorded in other two continents, Latin America and Australia, where it is causing massive damage on walnut and almond fruits. The sharing of a mitochondrial haplotype among populations recorded on three continents suggests that a worldwide invasion might be ongoing. A Geographic Profiling approach has determined that the more virulent population was first introduced in Italy, and the climate conditions of areas where C. truncatus is currently widespread and harmful indicate that the entire walnuts world production is in jeopardy as this species could adapt to any of the main walnut and almond production areas.

Artificial illumination near rivers may alter bat-insect trophic interactions.

Artificial illumination at night represents an increasingly concerning threat to ecosystems worldwide, altering persistence, behaviour, physiology and fitness of many organisms and their mutual interactions, in the long-term affecting ecosystem functioning. Bats are very sensitive to artificial light at night because they are obligate nocturnal and feed on insects which are often also responsive to lights. Here we tested the effects of LED lighting on prey-predator interactions at riverine ecosystems, using bats and their insect prey as models, and compared bat and insect reactions in terms of bat activity and prey insect abundance and diversity, respectively, on artificially lit vs. unlit nights. Artificial light influenced both insect and bat assemblages in taxon-specific directions: insect abundances increased at lit sites, particularly due to an increase in small dipterans near the light source. Composition of insect assemblages also differed significantly between lit and unlit sites. Total bat activity declined at lit sites, but this change was mainly due to the response of the most abundant species, Myotis daubentonii, while opportunistic species showed no reaction or even an opposite pattern (Pipistrellus kuhlii). We show that artificial lighting along rivers may affect trophic interactions between bats and insects, resulting in a profound alteration of community structure and dynamics.