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A large proportion of the insects which have invaded new regions and countries are emerging species, being found for the first time outside their native range. Being able to detect such species upon arrival at ports of entry before they establish in non-native countries is an urgent challenge. The deployment of traps baited with broad-spectrum semiochemical lures at ports-of-entry and other high-risk sites could be one such early detection tool. Rapid progress in the identification of semiochemicals for cerambycid beetles during the last 15 years has revealed that aggregation-sex pheromones and sex pheromones are often conserved at global levels for genera, tribes or subfamilies of the Cerambycidae. This possibly allows the development of generic attractants which attract multiple species simultaneously, especially when such pheromones are combined into blends. Here, we present the results of a worldwide field trial programme conducted during 2018-2021, using traps baited with a standardised 8-pheromone blend, usually complemented with plant volatiles. A total of 1308 traps were deployed at 302 sites covering simultaneously or sequentially 13 European countries, 10 Chinese provinces and some regions of the USA, Canada, Australia, Russia (Siberia) and the Caribbean (Martinique). We intended to test the following hypotheses: 1) if a species is regularly trapped in significant numbers by the blend on a continent, it increases the probability that it can be detected when it arrives in other countries/continents and 2) if the blend exerts an effective, generic attraction to multiple species, it is likely that previously unknown and unexpected species can be captured due to the high degree of conservation of pheromone structures within related taxa. A total of 78,321 longhorned beetles were trapped, representing 376 species from eight subfamilies, with 84 species captured in numbers greater than 50 individuals. Captures comprised 60 tribes, with 10 tribes including more than nine species trapped on different continents. Some invasive species were captured in both the native and invaded continents. This demonstrates the potential of multipheromone lures as effective tools for the detection of 'unexpected' cerambycid invaders, accidentally translocated outside their native ranges. Adding new pheromones with analogous well-conserved motifs is discussed, as well as the limitations of using such blends, especially for some cerambycid taxa which may be more attracted by the trap colour or other characteristics rather than to the chemical blend. [ABSTRACT FROM AUTHOR]

The present contribution reports the current distribution of the Asian scolytine beetle Anisandrus maiche Kurentzov (Curculionidae: Scolytinae, Xyleborini) in Italy. Previously, in the entire European Union, this species was known only from a single specimen collected in the Treviso province of Northeast Italy in 2021. The data presented here considerably increase the distributional range of A. maiche in Italy, and clearly show that this ambrosia beetle species is established and widespread in at least two northern Italian regions, namely Lombardy and Veneto. [ABSTRACT FROM AUTHOR]

Longhorn beetles are among the most important groups of invasive forest insects worldwide. In parallel, they represent one of the most well‐studied insect groups in terms of chemical ecology. Longhorn beetle aggregation‐sex pheromones are commonly used as trap lures for specific and generic surveillance programs at points of entry and may play a key role in determining the success or failure of exotic species establishment. An exotic species might be more likely to establish in a novel habitat if it relies on a pheromone channel that is different to that of native species active at the same time of year and day, allowing for unhindered mate location (i.e., pheromone‐free space hypothesis). In this study, we first tested the attractiveness of single pheromone components (i.e., racemic 3‐hydroxyhexan‐2‐one, racemic 3‐hydroxyoctan‐2‐one, and syn‐2,3‐hexanediol), and their binary and tertiary combinations, to native and exotic longhorn beetle species in Canada and Italy. Second, we exploited trap catches to determine their seasonal flight activity. Third, we used pheromone‐baited "timer traps" to determine longhorn beetle daily flight activity. The response to single pheromones and their combinations was mostly species specific but the combination of more than one pheromone component allowed catch of multiple species simultaneously in Italy. The response of the exotic species to pheromone components, coupled with results on seasonal and daily flight activity, provided partial support for the pheromone‐free space hypothesis. This study aids in the understanding of longhorn beetle chemical ecology and confirms that pheromones can play a key role in longhorn beetle invasions. [ABSTRACT FROM AUTHOR]

Bark and ambrosia beetles are commonly moved among continents within timber and fresh wood-packaging materials. Routine visual inspections of imported commodities are often complemented with baited traps set up in natural areas surrounding entry points. Given that these activities can be expensive, trapping protocols that attract multiple species simultaneously are needed. Here we investigated whether trapping protocols commonly used to detect longhorn beetles (Coleoptera: Cerambycidae) and jewel beetles (Coleoptera: Buprestidae) can be exploited also for detecting bark and ambrosia beetles. In factorial experiments conducted in 2016 both in Italy (seminatural and reforested forests) and Canada (mixed forest) we tested the effect of trap color (green vs purple), trap height (understory vs canopy), and attractive blend (hardwood-blend developed for broadleaf-associated wood-boring beetles vs ethanol in Italy; hardwood-blend vs softwood-blend developed for conifer-associated wood-boring beetles, in Canada) separately on bark beetles and ambrosia beetles, as well as on individual bark and ambrosia beetle species. Trap color affected catch of ambrosia beetles more so than bark beetles, with purple traps generally more attractive than green traps. Trap height affected both beetle groups, with understory traps generally performing better than canopy traps. Hardwood-blend and ethanol performed almost equally in attracting ambrosia beetles in Italy, whereas hardwood-blend and softwood-blend were more attractive to broadleaf-associated species and conifer-associated species, respectively, in Canada. In general, we showed that trapping variables suitable for generic surveillance of longhorn and jewel beetles may also be exploited for survey of bark and ambrosia beetles, but trapping protocols must be adjusted depending on the forest type. [ABSTRACT FROM AUTHOR]

Several native species of bark- and wood-boring beetles (Coleoptera) have expanded their range within their native biogeographic regions in the last years, but the role of human activity in driving this phenomenon has been underinvestigated. Here we analyze 3 yr of trapping records of native bark- and wood-boring beetles (Cerambycidae and Scolytinae) collected at 12 Italian ports and their surrounding forests to help elucidate the human role in the movement of native species within their native biogeographic region. We trapped several species that occurred either inside or outside their native distributional range within Italy. Species richness and abundance of those species found in the ports located within their native range were most strongly associated with the amount of forest cover in the surrounding landscape, suggesting that they could have arrived in the ports from the nearby forests. The abundance of the species found outside their native range was instead most strongly linked to the amount of national imports arriving at the port where trapping occurred, suggesting that they were likely introduced to the ports from other parts of Italy. This study demonstrates that national sea transportation can favor species range expansion within a country, and confirms that the forests that surround ports can serve as a source of species that can be potentially moved with exports. [ABSTRACT FROM AUTHOR]

Non-native wood-boring beetles (Coleoptera) represent one of the most commonly intercepted groups of insects at ports worldwide. The development of early detection methods is a crucial step when implementing rapid response programs so that non-native wood-boring beetles can be quickly detected and a timely action plan can be produced. However, due to the limited resources often available for early detection, it is important to identify the best locations where to concentrate surveillance efforts. The aim of this study was to investigate the role of wood waste landfills in the early detection of non-native wood-boring beetles. From June to September 2013, insects were collected in multi-funnel traps baited with a multi-lure blend (α-pinene, ethanol, ipsdienol, ipsenol, and methyl-butenol) at the main port and a nearby wood waste landfill in 12 Italian towns. Overall, 74 species of wood-boring beetles (Buprestidae, Cerambycidae, and Scolytinae) were trapped, among which eight were non-native to Italy. We found that species richness and species abundance of both non-native and native beetles were significantly higher in the wood waste landfill than in the ports. However, the non-native and native communities were similar in the two environments. The main conclusion emerging from this study is that wood waste landfills, given their similarity with ports of entry, should be considered when surveying for non-native wood-boring beetles. Therefore, within the framework of creating long-term monitoring programs that include both coastal and continental areas, both ports and wood waste landfills should be monitored to improve the probability for early detection of non-native species. [ABSTRACT FROM AUTHOR]