Edoardo Petrucco Toffolo

Exploring associations between international trade and environmental factors with establishment patterns of exotic Scolytinae

Although invasion of exotic ambrosia beetles (fungus feeders) and bark beetles (phloem feeders) (Coleoptera: Curculionidae: Scolytinae) is considered a major threat to forest health worldwide, no studies have quantitatively investigated the anthropogenic and environmental factors shaping the biogeographical patterns of invasion by these insects across large spatial scales. The primary aim of this study was to assess the relative importance of international trade and several environmental variables of the recipient region on species richness of established exotic Scolytinae. As a reference, we also evaluated the relationships between the same environmental variables and species richness of native Scolytinae. Using an information-theoretic framework for model selection and hierarchical partitioning, we evaluated the relative importance of the potential drivers of species richness of native and exotic Scolytinae in 20 European countries and the 48 contiguous continental US states. Analyses were conducted separately for ambrosia and bark beetle species. Value of imports was a strong predictor of the number of exotic Scolytinae species in both regions. In addition, in the USA, warmer and wetter climate was positively linked to increased numbers of both native and exotic ambrosia beetles. Forest heterogeneity and climatic heterogeneity and secondarily forest area were key drivers in explaining patterns of species richness for native bark beetles but not for exotic species in both regions. Our findings suggest that if current infestation levels continue on imported plants and wood packaging material, increasing international trade will likely lead to more establishments of exotic Scolytinae with concomitant negative effects on forest health in both Europe and the USA. Compared to Europe the risk of invasion appears higher in the USA, especially for ambrosia beetles in the southeastern USA where the climate appears highly suitable for exotic establishment.

Improving the early detection of alien wood-boring beetles in ports and surrounding forests

Summary 1. International ports are generally considered the most likely points of entry for alien woodboring beetles. A better understanding of the factors affecting their arrival and establishment at ports and their surrounding areas is of utmost importance to improve the efficacy and the cost-effectiveness of early detection programmes. Our work aimed at understanding how port size and the characteristics of the landscape surrounding the port, in terms of forest cover and forest composition, influence the occurrence of alien wood-boring beetles. 2. From May to September 2012, 15 Italian international ports and the surrounding forests were monitored with multi-funnel traps baited with a multi-lure blend (a-pinene, ethanol, ipsdienol, ipsenol, methyl-butenol), three in each port and three in forests located 3–5 km away from the port. We identified both alien and native Scolytinae, Cerambycidae and Buprestidae beetles. 3. Fourteen alien species, among which four are new to Italy, were trapped. Alien species richness was positively related to the amount of imported commodities at the port scale. Broadleaf forests surrounding ports received larger number of alien species than conifer forests. By contrast, total forest cover in the landscape surrounding ports was positively related to the occurrence of native but not alien species. The alien and native species richness was higher in the surrounding forests than in the ports. 4. Synthesis and applications. The simultaneous use of traps in ports with large volume of imported commodities and in their surrounding broadleaf forests can strongly increase the probability of alien wood-boring beetle interceptions. The identification of sites where the arrival and establishment of alien species is more probable, combined with an efficient trapping protocol, can substantially improve the efficacy of early detection. Similar approaches may be used in other countries as early warning systems to implement timely measures to eradicate or contain alien invasions at the European scale.

Survival at low temperature of larvae of the pine processionary moth Thaumetopoea pityocampa from an area of range expansion.

1 Larvae of Thaumetopoea pityocampa (Lepidoptera: Notodontidae) develop throughout the winter, although their feeding activity and survival can be impaired by adverse climatic factors. The present study investigated the survival at low temperature of larvae originating from a population with range expansion in an alpine valley in Northern Italy.

Exploring the role of wood waste landfills in early detection of non-native wood-boring beetles

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.

Size and dispersion of urticating setae in three species of processionary moths

Larvae of the processionary moths of the Palaearctic region bear urticating setae that are released against vertebrate predators, especially insectivorous birds. A few species are pests of forest and urban trees and, consequently, may threaten human and animal health during outbreaks, causing dermatitis, conjunctivitis and respiratory distress. Although some studies provide detailed information about the setae, particularly those of the pine processionary moth Thaumetopoea pityocampa, there is little knowledge on the morphological traits of the setae and their release by the larvae. In the present study we identify major traits of the setae of 3 species of processionary moth, T. pityocampa, T. pinivora and T. processionea, which are potentially helpful in the understanding of setae dynamics in the environment: (i) diameter and length of setae and (ii) analysis of dynamical properties of the setae in the airborne state. Setae are highly variable in size, with bimodal distribution in T. pityocampa and T. pinivora; in these 2 species, short and long setae are interspersed within the integument fields where they occur. The difference in the seta size has important consequences in dispersion, as smaller setae can spread 5 times further than their bigger counterparts. This information is relevant for a full understanding of the defensive importance of larval setae against natural enemies of the processionary moths, as well for elucidating the importance of the processionary setae as air pollutants, both close to the infested trees and at longer distances.

First record of Cyrtogenius Strohmeyer in Europe, with a key to the European genera of the tribe Dryocoetini (Coleoptera: Curculionidae, Scolytinae).

The genus Cyrtogenius Strohmeyer, represented by the species C. luteus (Blandford, 1894), is reported for the first time in Europe. Many adults were collected for four consecutive years (2009–2012) in various localities of northern Italy in both multifunnel and cross-vane traps baited with multilure blends. A diagnosis of the species and a revised key to the European genera of tribe Dryocoetini Lindemann is also reported. An explanation is suggested for the increasing number of recent introductions of exotic scolytids into Europe.

Medical and Veterinary Impact of the Urticating Processionary Larvae

This chapter presents recent findings on the impact of processionary moths on human and animal health. The data obtained demonstrate that setae can be dispersed kms away from their origin, a fact that explains why some sensitized subjects experience symptoms without a direct contact with larvae.

Bark and Ambrosia Beetles Show Different Invasion Patterns in the USA.

Non-native bark and ambrosia beetles represent a threat to forests worldwide. Their invasion patterns are, however, still unclear. Here we investigated first, if the spread of non-native bark and ambrosia beetles is a gradual or a discontinuous process; second, which are the main correlates of their community structure; third, whether those correlates correspond to those of native species. We used data on species distribution of non-native and native scolytines in the continental 48 USA states. These data were analyzed through a beta-diversity index, partitioned into species richness differences and species replacement, using Mantel correlograms and non-metric multidimensional scaling (NMDS) ordination for identifying spatial patterns, and regression on distance matrices to test the association of climate (temperature, rainfall), forest (cover area, composition), geographical (distance), and human-related (import) variables with β-diversity components. For both non-native bark and ambrosia beetles, β-diversity was mainly composed of species richness difference than species replacement. For non-native bark beetles, a discontinuous invasion process composed of long distance jumps or multiple introduction events was apparent. Species richness differences were primarily correlated with differences in import values while temperature was the main correlate of species replacement. For non-native ambrosia beetles, a more continuous invasion process was apparent, with the pool of non-native species arriving in the coastal areas that tended to be filtered as they spread to interior portions of the continental USA. Species richness differences were mainly correlated with differences in rainfall among states, while rainfall and temperature were the main correlates of species replacement. Our study suggests that the different ecology of bark and ambrosia beetles influences their invasion process in new environments. The lower dependency that bark beetles have on climate allowed them to potentially colonize more areas within the USA, while non-native ambrosia beetles, being dependent on rainfall, are typically filtered by the environment.

Figure 2. Antennal Funicle 4 In First Record Of Cyrtogenius Strohmeyer In Europe, With A Key To The European Genera Of The Tribe Dryocoetini (Coleoptera: Curculionidae, Scolytinae)

FIGURE 2. Antennal funicle 4 - segmented of Cyrtogenius luteus. Note also the antennal club obliquely truncated with a basal corneous portion and sutures visible only on the anterior face.