Optimal allocation of resources among general and species-specific tools for plant pest biosecurity surveillance

This paper proposes a surveillance model for plant pests that can optimally allocate resources among survey tools with varying properties. While some survey tools are highly specific for the detection of a single pest species, others are more generalized. There is considerable variation in the cost and sensitivity of these tools, but there are no guidelines or frameworks for identifying which tools are most cost-effective when used in surveillance programs that target the detection of newly invaded populations. To address this gap, we applied our model to design a trapping surveillance program in New Zealand for bark- and wood-boring insects, some of the most serious forest pests worldwide. Our findings show that exclusively utilizing generalized traps (GTs) proves to be highly cost-effective across a wide range of scenarios, particularly when they are capable of capturing all pest species. Implementing surveillance programs that only employ specialized traps (ST) is cost-effective only when these traps can detect highly damaging pests. However, even in such cases, they significantly lag in cost-effectiveness compared to GT-only programs due to their restricted coverage. When both GTs and STs are used in an integrated surveillance program, the total expected cost (TEC) generally diminishes when compared to programs relying on a single type of trap. However, this relative reduction in TEC is only marginally larger than that achieved with GT-only programs, as long as highly damaging species can be detected by GTs. The proportion of STs among the optimal required traps fluctuates based on several factors, including the relative pricing of GTs and STs, pest arrival rates, potential damage, and, more prominently, the coverage capacity of GTs. Our analysis suggests that deploying GTs extensively across landscapes appears to be more cost-effective in areas with either very high or very low levels of relative risk density, potential damage, and arrival rate. Finally, STs are less likely to be required when the pests that are detected by those tools have a higher likelihood of successful eradication because delaying detection becomes less costly for these species.

Fusarium kuroshium is the primary fungal symbiont of an ambrosia beetle, Euwallacea fornicatus, and can kill mango tree in Japan

This study identifies fungi associated with Euwallacea fornicatus and determines whether these fungal species play the role of primary symbiont. E. fornicatus adults that emerged from the branches of infested trees in Okinawa main island, Japan, were collected and used to isolate fungi. Fusarium kuroshium and Penicillium citrinum were the most dominant fungal associates of females and males, respectively. F. kuroshium was much more frequently isolated from the head, including mycangia (fungus-carrying organs), of females than any other body parts. We inoculated healthy mango saplings with F. kuroshium or F. decemcellulare, both of which were symbionts of E. fornicatus females infesting mango trees. F. kuroshium decreased leaf stomatal conductance and rate of xylem sap-conduction area and increased length and area of xylem discoloration of the saplings, thereby weakening and killing some. These results suggest that F. kuroshium, a mycangial fungus of E. fornicatus, inhibits water flow in mango trees. This study is the first to report that F. kuroshium causes wilt disease in mango trees and that it is a primary fungal symbiont of E. fornicatus.

Veni, vidi, vici? Future spread and ecological impacts of a rapidly expanding invasive predator population

Economic and ecological consequences of invasive species make biological invasions an influential driver of global change. Monitoring the spread and impacts of non-native species is essential, but often difficult, especially during the initial stages of invasion. The Jorō spider, Trichonephila clavata (L. Koch, 1878, Araneae: Nephilidae), is a large-bodied orb weaver native to Asia, likely introduced to northern Georgia, U.S. around 2010. We investigated the nascent invasion of T. clavata by constructing species distribution models (SDMs) from crowd-sourced data to compare the climate T. clavata experiences in its native range to its introduced range. We found evidence that the climate of T. clavata's native range differs significantly from its introduced range. Species distribution models trained with observations from its native range predict that the most suitable habitats in North America occur north of its current introduced range. Consistent with SDM predictions, T. clavata appears to be spreading faster to the north than to the south. Lastly, we conducted surveys to investigate potential ecological impacts of T. clavata on the diversity of native orb weaving spiders. Importantly, Trichonephila clavata was the most common and abundant species observed in the survey, and was numerically dominant at half of the sites it was present in. Our models also suggest that there is lower native orb weaver species richness and diversity closer to where T. clavata was initially found and where it has been established the longest, though human population density complicates this finding. This early study is the first to forecast how widely this spider may spread in its introduced range and explore its potential ecological impacts. Our results add evidence that T. clavata is an invasive species and deserves much more ecological scrutiny.

The Global Forest Health Crisis: A Public-Good Social Dilemma in Need of International Collective Action

Society is confronted by interconnected threats to ecological sustainability. Among these is the devastation of forests by destructive non-native pathogens and insects introduced through global trade, leading to the loss of critical ecosystem services and a global forest health crisis. We argue that the forest health crisis is a public-good social dilemma and propose a response framework that incorporates principles of collective action. This framework enables scientists to better engage policymakers and empowers the public to advocate for proactive biosecurity and forest health management. Collective action in forest health features broadly inclusive stakeholder engagement to build trust and set goals; accountability for destructive pest introductions; pooled support for weakest-link partners; and inclusion of intrinsic and nonmarket values of forest ecosystems in risk assessment. We provide short-term and longer-term measures that incorporate the above principles to shift the societal and ecological forest health paradigm to a more resilient state.

Conceptualizing the human drivers of low tree diversity in planted urban landscapes

Despite the abundance of tree diversity in the natural world, and generally high tree species richness in urban areas, urban forests continue to be dominated by a limited number of species. As socio-ecological systems, urban forests are shaped by historical and current management efforts and decision-making across a wide range of human actors. Drawing on past research, we offer a conceptual framework for describing the complex interactions among tree producers and consumers as trees are selected, grown, specified, and planted in private and public urban areas. We illustrate how multiple layers of selection criteria filter down the entirety of potential local tree diversity to a handful of commonly used and accepted tree species. We detail the actors and decision-makers who impact tree composition and diversity across several land types. Finally, we identify research, education, and outreach needs as they relate to creating more diverse and resilient urban forest ecosystems.

Type and duration of water stress influence host selection and colonization by exotic ambrosia beetles (Coleoptera: Curculionidae)

Fungus-farming ambrosia beetles in the tribe Xyleborini tunnel into plants and trees to establish chambers for cultivating their nutritional fungal mutualists and rearing offspring. Some xyleborine ambrosia beetles preferentially infest and perform better in living but weakened trees. Flood stress predisposes horticultural tree crops to infestation, but the impact of drought stress has not been well studied. Our objectives were to compare the effects of flood stress vs. drought stress on host selection and colonization by xyleborine ambrosia beetles and to assess the duration of flooding. Container-grown Cornus florida L. trees were flood stressed using a pot-in-pot system to submerge the roots in water while drought-stressed conditions were imposed by withholding irrigation and precipitation. When experimental trees were held under field conditions for 14 days, 7.5 × more ambrosia beetles landed on stems of the flood-stressed than on the drought-stressed trees. During two additional experiments over 14 and 22 days, ambrosia beetles tunneled into the flood-stressed trees but not the drought-stressed or standard irrigation trees. By simultaneously deploying trees that were flood stressed for varying lengths of time, it was found that more tunnel entrances, and xyleborine adults and offspring were recovered from trees that were flooded for 1-16 days and 7-22 days than from trees that were flooded for 14-29 days and 28-43 days. These results indicate that acute and severe drought stress does not predispose C. florida to infestation, but flood stress and the duration of flooding influence ambrosia beetle host selection and colonization. Understanding the role of host quality on ambrosia beetle preference behavior will assist with predicting the risk of infestation of these opportunistic insects in horticultural tree crops.

Can morphological traits explain species-specific differences in meta-analyses? A case study of forest beetles

Meta-analyses have become a valuable tool with which to synthesize effects across studies, but in ecology and evolution, they are often characterized by high heterogeneity, where effect sizes vary between studies. Much of this heterogeneity can be attributed to species-specific differences in responses to predictor variables. Here, we aimed to incorporate a novel trait-based approach to explain species-specific differences in a meta-analysis by testing the ability of morphological traits to explain why the effectiveness of flight-intercept trap design varies according to beetle species, a critical issue in forest pest management. An existing morphological trait database for forest beetles was supplemented, providing trait data for 97 species, while data from a previous meta-analysis on capture rates of bark or woodboring beetles according to different trap designs were updated. We combined these sources by including nine morphological traits as moderators in meta-analysis models, for five different components of trap design. Traits were selected based on theoretical hypotheses relating to beetle movement, maneuverability, and sensory perception. We compared the performance of morphological traits as moderators versus guild, taxonomic family, and null meta-analysis models. Morphological traits for the effect of trap type (panel vs. multiple-funnel) on beetle capture rates improved model fit (AIC_c ), reduced within-study variance (σ² ), and explained more variation (McFadden's pseudo-R² ) compared with null, guild, and taxonomic family models. For example, morphological trait models explained 10% more of the variance (pseudo-R² ) when compared with a null model. However, using traits was less informative to explain how detailed elements of trap design such as surface treatment and color influence capture rates. The reduction of within-study variance when accounting for morphological traits demonstrates their potential value for explaining species-specific differences. Morphological traits associated with flight efficiency, maneuverability, and eye size were particularly informative for explaining the effectiveness of trap type. This could lead to improved predictability of optimal trap design according to species. Therefore, morphological traits could be a valuable tool for understanding species-specific differences in community ecology, but other causes of heterogeneity across studies, such as forest type and structure, require further investigation.

Phylogenetic risk assessment is robust for forecasting the impact of European insects on North American conifers

Some introduced species cause severe damage, although the majority have little impact. Robust predictions of which species are most likely to cause substantial impacts could focus efforts to mitigate those impacts or prevent certain invasions entirely. Introduced herbivorous insects can reduce crop yield, fundamentally alter natural and managed forest ecosystems, and are unique among invasive species in that they require certain host plants to succeed. Recent studies have demonstrated that understanding the evolutionary history of introduced herbivores and their host plants can provide robust predictions of impact. Specifically, divergence times between hosts in the native and introduced ranges of a nonnative insect can be used to predict the potential impact of the insect should it establish in a novel ecosystem. However, divergence time estimates vary among published phylogenetic datasets, making it crucial to understand if and how the choice of phylogeny affects prediction of impact. Here, we tested the robustness of impact prediction to variation in host phylogeny by using insects that feed on conifers and predicting the likelihood of high impact using four different published phylogenies. Our analyses ranked 62 insects that are not established in North America and 47 North American conifer species according to overall risk and vulnerability, respectively. We found that results were robust to the choice of phylogeny. Although published vascular plant phylogenies continue to be refined, our analysis indicates that those differences are not substantial enough to alter the predictions of invader impact. Our results can assist in focusing biosecurity programs for conifer pests and can be more generally applied to nonnative insects and their potential hosts by prioritizing surveillance for those insects most likely to be damaging invaders.

Forest Insect Biosecurity: Processes, Patterns, Predictions, Pitfalls

The economic and environmental threats posed by non-native forest insects are ever increasing with the continuing globalization of trade and travel; thus, the need for mitigation through effective biosecurity is greater than ever. However, despite decades of research and implementation of preborder, border, and postborder preventative measures, insect invasions continue to occur, with no evidence of saturation, and are even predicted to accelerate. In this article, we review biosecurity measures used to mitigate the arrival, establishment, spread, and impacts of non-native forest insects and possible impediments to the successful implementation of these measures. Biosecurity successes are likely under-recognized because they are difficult to detect and quantify, whereas failures are more evident in the continued establishment of additional non-native species. There are limitations in existing biosecurity systems at global and country scales (for example, inspecting all imports is impossible, no phytosanitary measures are perfect, knownunknowns cannot be regulated against, and noncompliance is an ongoing problem). Biosecurity should be a shared responsibility across countries, governments, stakeholders, and individuals.

When the Beetles Hit the Fan: The Fan-Trap, an Inexpensive, Light and Scalable Insect Trap under a Creative Commons License, for Monitoring and Experimental Use

Monitoring is an important component in pest management, to prevent or mitigate outbreaks of native pests and to check for quarantine organisms. Surveys often rely on trapping, especially when the target species respond to semiochemicals. Many traps are available for this purpose, but they are bulky in most cases, which raises transportation and deployment issues, and they are expensive, which limits the size and accuracy of any network. To overcome these difficulties, entomologists have used recycled material, such as modified plastic bottles, producing cheap and reliable traps but at the cost of recurrent handywork, not necessarily possible for all end-users (e.g., for national plant-protection organizations). These bottle-traps have allowed very large surveys to be conducted, which would have been impossible with standard commercial traps, and we illustrate this approach with a few examples. Here, we present, under a Creative Commons BY-SA License, the blueprint for a fan-trap, a foldable model, laser cut from a sheet of polypropylene, which can rapidly be produced in large numbers in a Fab lab or by a commercial company and could be transported and deployed in the field with very little effort. Our first field comparisons show that fan-traps are as efficient as bottle-traps for some Scolytinae species and we describe two cases where they are being used for monitoring.

New species and new records of exotic Scolytinae (Coleoptera, Curculionidae) in Europe

Background

Bark and ambrosia beetles (Coleoptera, Scolytinae) are amongst the most important wood-boring insects introduced to Europe. During field investigations conducted between 2019 and 2021 in different countries and regions of Europe, many exotic species have been recorded providing new and relevant data.

New information

Dryoxylononoharaense (Murayama, 1933) is recorded in Europe for the first time. Xyleborinusattenuatus (Blandford, 1894) is a species new to Italy, while Xylosandrusgermanus (Blandford, 1894), Hypothenemuseruditus (Westwood, 1836) and Amasa sp. near A.truncata are new country records for Portugal. Cnestusmutilatus (Blandford, 1894), Phloeotribusliminaris (Harris, 1852) were collected in Italy and Amasa sp. near A.truncata was collected in France after the first discovery, confirming their establishment and their dispersal into new areas.

Ambrosia Beetle Occurrence and Phenology of Xylosandrus spp. (Coleoptera: Curculionidae: Scolytinae) in Ornamental Nurseries, Tree Fruit, and Pecan Orchards in Georgia

Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae, Platypodinae) in the genus Xylosandrus are problematic in ornamental nurseries and are emerging as serious pests in orchard crops. An updated survey of ambrosia beetles focusing on these damaging species, and their corresponding phenology was conducted in Georgia to aid in refining management practices for these beetles. Ambrosia beetles were monitored across nine sites in 2019 and seven sites 2020 at ornamental nurseries, tree fruit, and pecan orchards in Georgia. At each site, six ethanol-baited bottle traps were deployed; with three traps along the edge of a wood-line and three traps placed 30 m from the edge of the nurseries and orchards. Traps were deployed from mid-January through July or August depending on site and year. All captured ambrosia beetles were counted and identified. Captures of X. crassiusculus, X. germanus, and X. compactus, were analyzed further to investigate spatial distribution and seasonal flight activity. At high population sites, more beetles were captured along adjacent wood lines than in the orchard or nursery interior. At most sites, flight activity began in February and March continued until the termination of the study in July or August. At most sites, sustained flight activities with multiple peaks were observed in March, April, and May, corresponding to average weekly temperatures reaching ≥15.5°C. These results have important implications on temporally and spatially precise management for these beetles across three important agricultural production systems in the southeastern US.

New Canadian and Provincial Records of Coleoptera Resulting from Annual Canadian Food Inspection Agency Surveillance for Detection of Non-Native, Potentially Invasive Forest Insects

The arrival and establishment of adventive, invasive forest insects are a threat to the health, diversity, and productivity of forests in Canada and the world at large, and their early detection is essential for successful eradication and management. For that reason, the Canadian Food Inspection Agency (CFIA) conducts annual surveys at high risk sites such as international ports and freight terminals, industrial zones, and disposal sites for solid wood packaging material using two methods: (1) semiochemical-baited traps deployed in a total of about 63-80 sites per year in British Columbia (BC), Ontario (ON), Quebec (QC), New Brunswick (NB), Nova Scotia (NS), and Newfoundland and Labrador (NL); and (2) rearing of insects from bolts collected from stressed trees and incubated in modified shipping containers in four cities (Vancouver, Toronto, Montreal, and Halifax). We report 31 new Canadian provincial records of Coleoptera from surveys conducted in 2011-2021, including 13 new records for Canada and 9 species adventive to North America (indicated by †). Nine of the new Canadian records were native North American species previously detected only south of the border. All but three species belong to the Curculionidae family and most of these were in the subfamily Scolytinae. The records include: Xenomelanophila miranda (LeConte) (Canada, BC) (Buprestidae: Buprestinae); Neoclytus mucronatus mucronatus (Fabricius) (BC) (Cerambycidae: Cerambycinae); Amphicerus cornutus (Pallas) (Canada, BC) (Bostrichidae: Bostrichinae); Mecinus janthinus (Germar)† (ON) (Curculionidae: Curculioninae); Aulacobaris lepidii (Germar)† (Canada, ON); Buchananius striatus (LeConte) (ON) (Curculionidae: Baridinae); Cylindrocopturus binotatus LeConte (Canada, ON) (Curculionidae: Conoderinae); Himatium errans LeConte (ON); Phloeophagus canadensis Van Dyke (ON); Rhyncolus spretus Casey (Canada, BC); Stenomimus pallidus (Boheman) (Canada, ON); Tomolips quercicola (Boheman) (Canada, ON) (Curculionidae: Cossoninae); Strophosoma melanogrammum (Forster)† (NB) (Curculionidae: Entiminae); Conotrachelus aratus (Germar) (ON) (Curculionidae: Molytinae); Anisandrus maiche Stark† (Canada, ON, QC); Cnesinus strigicollis LeConte (Canada, ON); Cyclorhipidion pelliculosum (Eichhoff)† (Canada, ON, QC); Hylesinus fasciatus LeConte (QC); Hylesinus pruinosus Eichhoff (QC); Hypothenemus interstitialis (Hopkins) (Canada, ON); Lymantor alaskanus Wood (BC); Pityogenes bidentatus (Herbst)† (Canada, ON); Scolytus mali (Bechstein)† (BC); Scolytus schevyrewi Semenov† (QC); Trypodendron scabricollis (LeConte) (Canada, ON); Trypophloeus populi Hopkins (QC); Xylechinus americanus Blackman (NFLB); and Xylosandrus crassiusculus (Motschulsky)† (BC, QC) (Curculionidae: Scolytinae). We also provide additional data confirming the presence of the adventive Hylastes opacus Erichson† in NS. Rearing of insects from bolts accounted for two new records (H. pruinosus, R. spretus) and trapping accounted for the remainder. These surveys not only assist our efforts to manage forest insects by documenting new species introductions and apparent range expansions but also increase our knowledge of biodiversity.

Cerambycid Pheromones 3,2-Hydroxyketones Affect Catches of Some Bark and Ambrosia Beetles (Coleoptera: Curculionidae) in Ethanol-Baited Multiple-Funnel Traps in Southeastern United States

In 2012-2013, we assessed the interactive effects of the cerambycid pheromones syn-2,3-hexanediol, 3-hydroxyhexan-2-one, and 3-hydroxyoctan-2-one on catches of bark and ambrosia beetles (Coleoptera: Curculionidae) in ethanol-baited multiple-funnel traps in north Georgia and South Carolina. We found that catches for nine of eleven species of ambrosia beetles in ethanol-baited traps were either unaffected or enhanced by the addition of 3,2-hydroxyketones. Similarly catches of five species of bark beetles were either unaffected or enhanced by the addition of 3,2-hydroxyketones. In particular, catches of Xylosandrus crassiusculus (Motschulsky), Cnestus mutilatus (Blandford), and Monarthrum fasciatum (Say) in ethanol-baited traps increased with the addition of 3-hydroxyhexan-2-one and/or 3-hydroxyoctan-2-one. Catches of the bark beetles Hylocurus rudis (LeConte) and Hypothenemus rotundicollis (Eichhoff) were enhanced by the addition of 3-hydroxyhexan-2-one and 3-hydroxyoctan-2-one, respectively. syn-2,3-Hexanediol had no effect on catches of bark and ambrosia beetles in ethanol-baited traps. Our data provide support for the use of ethanol + cerambycid pheromones for targeting non-native species of bark and ambrosia beetles as well as cerambycids in detection programs.

Ecuadorian Coptoborus beetles harbor Fusarium and Graphium fungi previously associated with Euwallacea ambrosia beetles

Ambrosia beetles from the scolytine tribe Xyleborini (Curculionidae) are important to the decomposition of woody plant material on every continent except Antarctica. These insects farm fungi on the walls of tunnels they build inside recently dead trees and rely on the fungi for nutrition during all stages of their lives. Such ambrosia fungi rely on the beetles to provide appropriate substrates and environmental conditions for growth. A small minority of xyleborine ambrosia beetle-fungal partnerships cause significant damage to healthy trees. The xyleborine beetle Coptoborus ochromactonus vectors a Fusarium (Hypocreales) fungus that is lethal to balsa (Ochroma pyramidale (Malvaceae)) trees in Ecuador. Although this pathogenic fungus and its associated beetle are not known to be established in the United States, several other non-native ambrosia beetle species are vectors of destructive plant diseases in this country. This fact and the acceleration of trade between South America and the United States demonstrate the importance of understanding fungal plant pathogens before they escape their native ranges. Here we identify the fungi accompanying Coptoborus ambrosia beetles collected in Ecuador. Classification based ribosomal internal transcribed spacer 1 (ITS) sequences revealed the most prevalent fungi associated with Coptoborus are Fusarium sp. and Graphium sp. (Microascales: Microascaceae), which have been confirmed as ambrosia fungi for xyleborine ambrosia beetles, and Clonostsachys sp. (Hypocreales), which is a diverse genus found abundantly in soils and associated with plants. Phylogenetic analyses of the Fusarium strains based on ITS, translation elongation factor (EF1-α), and two subunits of the DNA-directed RNA polymerase II (RPB1 and RPB2) identified them as Fusarium sp. AF-9 in the Ambrosia Fusarium Clade (AFC). This Fusarium species was previously associated with a few xyleborine ambrosia beetles, most notably the species complex Euwallacea fornicatus (Eichhoff 1868) (Curculionidae: Scolytinae: Xyleborini). Examination of ITS and EF1-α sequences showed a close affinity between the Graphium isolated from Coptoborus spp. and other xyleborine-associated Graphium as well as the soil fungus Graphium basitruncatum. This characterization of ambrosia fungi through DNA sequencing confirms the identity of a putative plant pathogen spread by Coptoborus beetles and expands the documented range of Fusarium and Graphium ambrosia fungi.

Collecting and preserving bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae & Platypodinae)

This protocol describes the different methods to collect and preserve bark and ambrosia beetles, detailing collecting tools, recording relevant data, and optimizing step-by-step methods to extract beetles from twigs, branches, bark, and trunks. It elaborates on trapping techniques, tools, lures, baits, and beetle preservation. The main rule of manual collecting is to not attempt to pry the insect out of the wood or bark, but instead, remove the wood/bark away from the beetle: gently and systematically. The main rule of trapping is that there is no general attractant; instead, attractants and traps should reflect the ecology of the targeted beetle taxa.

Designing a Pest and Disease Outbreak Warning System for Farmers, Agronomists and Agricultural Input Distributors in East Africa

Simple Summary

Designing early warning systems for threats to food crops in Africa must respond to the needs of potential users of the system. This paper provides evidence from professional distributors, retailers, researchers, and agronomists in East Africa who may be able to use and communicate the results of the predictive modeling of pest outbreaks. Understanding the timing and spatial extent of required warnings will help guide research and engagement in these rapidly commercializing countries.

Abstract

Early warnings of the risks of pest and disease outbreaks are becoming more urgent, with substantial increases in threats to agriculture from invasive pests. With geospatial data improvements in quality and timeliness, models and analytical systems can be used to estimate potential areas at high risk of yield impacts. The development of decision support systems requires an understanding of what information is needed, when it is needed, and at what resolution and accuracy. Here, we report on a professional review conducted with 53 professional agronomists, retailers, distributors, and growers in East Africa working with the Syngenta Foundation for Sustainable Agriculture. The results showed that respondents reported fall armyworm, stemborers and aphids as being among the most common pests, and that crop diversification was a key strategy to reduce their impact. Chemical and cultural controls were the most common strategies for fall armyworm (FAW) control, and biological control was the least known and least used method. Of the cultural control methods, monitoring and scouting, early planting, and crop rotation with non-host crops were most used. Although pests reduced production, only 55% of respondents were familiar with early warning tools, showing the need for predictive systems that can improve farmer response.

Effect of Host Volatile Release Rate and Racemic Fuscumol on Trap Catch of Hylurgus ligniperda, Hylastes ater (Coleoptera: Curculionidae), and Arhopalus ferus (Coleoptera: Cerambycidae)

Early detection of bark- and wood-boring beetles is critical to support the eradication of recently established populations in novel regions. Flight intercept traps baited with semiochemical lures are essential for surveillance and population monitoring of introduced insects. We present laboratory and field data to test potential improvements in trap sensitivity to detect Hylastes ater (Paykull), Hylurgus ligniperda (Fabricius) (Coleoptera:Scolytinae), and Arhopalus ferus (Mulsant) (Coleoptera:Cerambycidae). We evaluated the effects of type and permeability of plastic material on release rates of host-plant volatiles and the addition of the pheromone racemic E-fuscumol on beetle species catch within an exotic Pinus radiata (D. Don) plantation forest. We trapped 228,278 H. ligniperda, 91 H. ater, and 2,504 A. ferus over two experiments. Our results show strong attraction of H. ligniperda to host-plant volatiles with a positive relationship between increased release rates and trap catch. H. ater follows this trend, with attraction to ethanol and (-)-β-pinene. H. ligniperda was more strongly attracted to host volatiles than H. ater, the average ratio between baited and unbaited traps being 51.25:1 and 3.75:1, respectively for each species. There was no effect of host-plant volatiles or release rate on A. ferus catch, but a weak attraction by A. ferus to racemic E-fuscumol. Overall, we demonstrate species-specific differences in Coleoptera attraction to host-plant volatile release rates and semiochemical blends. Results demonstrate mechanisms to improve trap catch of H. ligniperda and H. ater. Racemic E-fuscumol shows some promise for A. ferus, but further investigation is required to determine whether chirality affects attraction.

Preinvasion Assessment of Exotic Bark Beetle-Vectored Fungi to Detect Tree-Killing Pathogens

Exotic diseases and pests of trees have caused continental-scale disturbances in forest ecosystems and industries, and their invasions are considered largely unpredictable. We tested the concept of preinvasion assessment of not yet invasive organisms, which enables empirical risk assessment of potential invasion and impact. Our example assesses fungi associated with Old World bark and ambrosia beetles and their potential to impact North American trees. We selected 55 Asian and European scolytine beetle species using host use, economic, and regulatory criteria. We isolated 111 of their most consistent fungal associates and tested their effect on four important southeastern American pine and oak species. Our test dataset found no highly virulent pathogens that should be classified as an imminent threat. Twenty-two fungal species were minor pathogens, which may require context-dependent response for their vectors at North American borders, while most of the tested fungi displayed no significant impact. Our results are significant in three ways; they ease the concerns over multiple overseas fungus vectors suspected of heightened potential risk, they provide a basis for the focus on the prevention of introduction and establishment of species that may be of consequence, and they demonstrate that preinvasion assessment, if scaled up, can support practical risk assessment of exotic pathogens.

Two new invasive Ips bark beetles (Coleoptera: Curculionidae) in mainland China and their potential distribution in Asia

BACKGROUND

Ips is a bark beetle genus of 45 species, many of which are pests of conifer forests and plantations under stress. Twelve Ips species are recorded from China and presumably native there. From 2016 to 2018, specimens suspected to be Ips calligraphus and Ips grandicollis, were collected from traps with ethanol as a sole lure in Zhuhai, Guangdong, China. Both species originate in North America and infest various species of native or introduced pines. Since Ips species are known to cause or exacerbate problems in pine plantations, and a regional survey using traps baited with attractants were implemented in this study to investigate the extent of the introduction.

RESULTS

Both I. calligraphus and I. grandicollis have been collected repeatedly from several traps with Ips attractants in Zhuhai, Guangdong, China since 2016. Potential distributions of these two species in Asia, inferred using MaxEnt, is extensive, given the high projected environmental suitability in North America, South America, Mediterranean Europe, Northern Africa, and Eastern Asia. The host plant of I. calligraphus from Zhuhai was identified as slash pine Pinus elliottii using DNA barcoding of gut contents from trapped individuals.

CONCLUSION

This is the first report of the establishment of two American pine bark beetles, I. calligraphus and I. grandicollis in continental Asia. The gut content of both species suggests that these pest feeds on a non-native host. Whether the two species present high-risk to Asian forests will become clear with more research on their interactions with native pines.

Comparative Meta-analysis Effects of Nonnative Ants (Hymenoptera: Formicidae), Ground Beetles (Coleoptera: Carabidae), and Bark and Ambrosia Beetles (Coleoptera: Curculionidae) on Native Confamilials

Nonnative species often transform local communities to the detriment of native species. Much of the existing invasion ecology research focuses on the effects of a few extremely impactful species, and it is less clear how nonnative species which are not causing economic or ecological impacts alter closely related natives at risk of being displaced. Filling these knowledge gaps is critical because consequences of nonnative species are likely to vary depending on taxonomic scale, functional trait, and spatial or temporal niche. We conducted a meta-analysis to evaluate how biodiversity of native Formicidae (ants), Carabidae (ground beetles), and Scolytinae (bark and ambrosia beetles) species changes across a gradient of pressure from nonnative confamilials. We calculated Hill numbers for each group from data presented in literature and correlated native diversity metrics to proportion of nonnative species. Species richness of native ants was significantly negatively correlated with proportions of nonnative ants, whereas bark and ambrosia beetle metrics showed a nonsignificant negative correlation. Nonnative ground beetles had neutral effects on diversity of native ground beetles. Resulting contrasting patterns of invasive species effects on natives suggest complex biotic and abiotic factors driving effects of nonnative species in these groups. Our results suggest that a few extreme examples (e.g., red imported fire ants) drive most of the changes seen in native arthropod communities. To accurately assess impacts of invaders on native arthropod diversity, baseline data are needed, and community analyses must consider diverse functional traits of native taxa and improve the depth and breadth of community sampling.

Response of native and exotic longhorn beetles to common pheromone components provides partial support for the pheromone-free space hypothesis

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.

Responses of Native and Non-native Bark and Ambrosia Beetles (Coleoptera: Curculionidae: Scolytinae) to Different Chemical Attractants: Insights From the USDA Forest Service Early Detection and Rapid Response Program Data Analysis

More than 60 non-native bark and ambrosia beetle species (Coleoptera: Curculionidae: Scolytinae) are established in North America and several have had severe negative impacts on ecosystems. Non-native scolytines can introduce fungi which may cause vascular wilts and compete with native fungi and lead to reductions in native species through host reduction. The Early Detection Rapid Response (EDRR) program was created by the USDA Forest Service in 2007 to detect non-native bark and ambrosia beetles and provide a baseline for tracking populations over time. This program has led to new collection records and increased communication among agencies to delimit non-native scolytine populations and perform appropriate management. Although insect responses to different lure types vary, it is unknown how different lures compare in attracting bark and ambrosia beetles. Our goal was to examine how lure combinations used in the EDRR program affect captures of bark and ambrosia beetle communities and to determine the most effective combination of lures for targeting non-native scolytines. The highest proportion of non-native scolytines was captured with ethanol, as was the greatest total number of species, and the most diverse beetle community. Traps with Ips (Coleoptera: Curculionidae) lures captured the highest proportion of native scolytines but the lowest total number of total species and was also the least diverse. Communities of scolytines differed significantly among lures, states, and years. While ethanol is an appropriate lure for generalist trapping and targeting a wide range of non-native bark and ambrosia beetles, more targeted lures are needed for monitoring certain species of non-natives.

Ambrosia Beetle (Coleoptera: Curculionidae) Communities and Frass Production in 'Ōhi'a (Myrtales: Myrtaceae) Infected With Ceratocystis (Microascales: Ceratocystidaceae) Fungi Responsible for Rapid 'Ōhi'a Death

Rapid 'Ōhi'a Death (ROD) is a deadly disease that is threatening the native Hawaiian keystone tree species, 'ōhi'a lehua (Metrosideros polymorpha Gaudich). Ambrosia beetles (Curculionidae: Scolytinae) and their frass are hypothesized to play a major role in the spread of ROD, although their ecological niches and frass production within trees and across the landscape are not well understood. We characterized the beetle communities and associated frass production from bolts (tree stem sections) representative of entire individual 'ōhi'a trees from multiple locations across Hawai'i Island by rearing beetles and testing their frass for viable ROD-causing fungi. Additionally, we estimated frass production for three beetle species by weighing their frass over time. We found that Xyleborinus saxesenii (Ratzburg), Xyleborus affinis Eichhoff, Xyleborus ferrugineus (Fabricius), Xyleborus perforans (Wollaston), and Xyleborus simillimus Perkins were commonly found on ROD-infected 'ōhi'a and each produced frass containing viable Ceratocystis propagules. The Hawai'i Island endemic beetle and the only native ambrosia beetle associated with 'ōhi'a, X. simillimus, was limited to high elevations and appeared to utilize similar tree heights or niche dimensions as the invasive X. ferrugineus. Viable Ceratocystis propagules expelled in frass were found throughout entire tree bole sections as high as 13 m. Additionally, we found that X. ferrugineus produced over 4× more frass than X. simillimus. Our results indicate the ambrosia beetle community and their frass play an important role in the ROD pathosystem. This information may help with the development and implementation of management strategies to control the spread of the disease.

Maximizing Bark and Ambrosia Beetle (Coleoptera: Curculionidae) Catches in Trapping Surveys for Longhorn and Jewel Beetles

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.

The Ambrosia Beetle Sueus niisimai (Scolytinae: Hyorrhynchini) is Associated with the Canker Disease Fungus Diatrypella japonica (Xylariales)

Ambrosia beetles in the subtribe Hyorrhynchini are one example of an entire ambrosia beetle lineage whose fungi have never been studied. Here, we identify one dominant fungus associated with a widespread Asian hyorrhynchine beetle Sueus niisimai. This fungus was consistently isolated from beetle galleries from multiple collections. Phylogenetic analyses of combined ITS rDNA and β-tubulin sequences identified the primary fungal symbiont as Diatrypella japonica Higuchi, Nikaido & Hattori (Diatrypaceae, Xylariales, Sordariomycetes), which was recently described as a pathogen of sycamore (Platanus spp.) in Japan. To assess the invasion potential of this beetle-fungus interaction into the U.S., we have investigated the pathogenicity of two D. japonica strains on four species of healthy landscape trees native to the southeastern United States. Only Shumard oak (Quercus shumardii) responded with lesions significantly greater than the control inoculations, but there was no observable dieback or tree mortality. Although disease symptoms were not as prominent as in previous studies of the same fungus in Japan, routine reisolation from the inoculation point suggests that this species is capable of colonizing healthy sapwood of several tree species. Our study shows that the geographical area of its distribution is broader in Asia and potentially includes many hosts of its polyphagous vector. We conclude that the Sueus-Diatrypella symbiosis has high invasion potential but low damage potential, at least on young trees during the growing season.

A monograph of the Xyleborini (Coleoptera, Curculionidae, Scolytinae) of the Indochinese Peninsula (except Malaysia) and China

The Southeast Asian xyleborine ambrosia beetle fauna is reviewed for the first time. Thirty-four genera and 315 species are reviewed, illustrated, and keyed to genera and species. Sixty-three new species are described: Amasa cycloxyster sp. nov., Amasa galeoderma sp. nov., Amasa gibbosa sp. nov., Amasa lini sp. nov., Amasa tropidacron sp. nov., Amasa youlii sp. nov., Ambrosiophilus caliginestris sp. nov., Ambrosiophilus indicus sp. nov., Ambrosiophilus lannaensis sp. nov., Ambrosiophilus papilliferus sp. nov., Ambrosiophilus wantaneeae sp. nov., Anisandrus achaete sp. nov., Anisandrus auco sp. nov., Anisandrus auratipilus sp. nov., Anisandrus congruens sp. nov., Anisandrus cryphaloides sp. nov., Anisandrus feronia sp. nov., Anisandrus hera sp. nov., Anisandrus paragogus sp. nov., Anisandrus sinivali sp. nov., Anisandrus venustus sp. nov., Anisandrus xuannu sp. nov., Arixyleborus crassior sp. nov., Arixyleborus phiaoacensis sp. nov., Arixyleborus setosus sp. nov., Arixyleborus silvanus sp. nov., Arixyleborus sittichayai sp. nov., Arixyleborus titanus sp. nov., Coptodryas amydra sp. nov., Coptodryas carinata sp. nov., Coptodryas inornata sp. nov., Cyclorhipidion amasoides sp. nov., Cyclorhipidion amputatum sp. nov., Cyclorhipidion denticauda sp. nov., Cyclorhipidion muticum sp. nov., Cyclorhipidion obesulum sp. nov., Cyclorhipidion petrosum sp. nov., Cyclorhipidion truncaudinum sp. nov., Cyclorhipidion xeniolum sp. nov., Euwallacea geminus sp. nov., Euwallacea neptis sp. nov., Euwallacea subalpinus sp. nov., Euwallacea testudinatus sp. nov., Heteroborips fastigatus sp. nov., Heteroborips indicus sp. nov., Microperus latesalebrinus sp. nov., Microperus minax sp. nov., Microperus sagmatus sp. nov., Streptocranus petilus sp. nov., Truncaudum bullatum sp. nov., Xyleborinus cuneatus sp. nov., Xyleborinus disgregus sp. nov., Xyleborinus echinopterus sp. nov., Xyleborinus ephialtodes sp. nov., Xyleborinus huifenyinae sp. nov., Xyleborinus jianghuansuni sp. nov., Xyleborinus thaiphami sp. nov., Xyleborinus tritus sp. nov., Xyleborus opacus sp. nov., Xyleborus sunisae sp. nov., Xyleborus yunnanensis sp. nov., Xylosandrus bellinsulanus sp. nov., Xylosandrus spinifer sp. nov.. Thirteen new combinations are given: Ambrosiophilus consimilis (Eggers) comb. nov., Anisandrus carinensis (Eggers) comb. nov., Anisandrus cristatus (Hagedorn) comb. nov., Anisandrus klapperichi (Schedl) comb. nov., Anisandrus percristatus (Eggers) comb. nov., Arixyleborus resecans (Eggers) comb. nov., Cyclorhipidion armiger (Schedl) comb. nov., Debus quadrispinus (Motschulsky) comb. nov., Heteroborips tristis (Eggers) comb. nov., Leptoxyleborus machili (Niisima) comb. nov., Microperus cruralis (Schedl) comb. nov., Planiculus shiva (Maiti & Saha) comb. nov., Xylosandrus formosae (Wood) comb. nov. Twenty-four new synonyms are proposed: Ambrosiophilus osumiensis (Murayama, 1934) (= Xyleborus nodulosus Eggers, 1941 syn. nov.); Ambrosiophilus subnepotulus (Eggers, 1930) (= Xyleborus cristatuloides Schedl, 1971 syn. nov.); Ambrosiophilus sulcatus (Eggers, 1930) (= Xyleborus sinensis Eggers, 1941 syn. nov.; = Xyleborus sulcatulus Eggers, 1939 syn. nov.); Anisandrus hirtus (Hagedorn, 1904) (= Xyleborus hirtipes Schedl, 1969 syn. nov.); Cnestus protensus (Eggers, 1930) (= Cnestus rostratus Schedl, 1977 syn. nov.); Cyclorhipidion bodoanum (Reitter, 1913) (= Xyleborus misatoensis Nobuchi, 1981 syn. nov.); Cyclorhipidion distinguendum (Eggers, 1930) (= Xyleborus fukiensis Eggers, 1941 syn. nov.; = Xyleborus ganshoensis Murayama, 1952 syn. nov.); Cyclorhipidion inarmatum (Eggers, 1923) (= Xyleborus vagans Schedl, 1977 syn. nov.); Debus quadrispinus (Motschulsky, 1863) (= Xyleborus fallax Eichhoff, 1878 syn. nov.); Euwallacea gravelyi (Wichmann, 1914) (= Xyleborus barbatomorphus Schedl, 1951 syn. nov.); Euwallacea perbrevis (Schedl, 1951) (= Xyleborus molestulus Wood, 1975 syn. nov.; Euwallacea semirudis (Blandford, 1896) (= Xyleborus neohybridus Schedl, 1942 syn. nov.); Euwallacea sibsagaricus (Eggers, 1930) (= Xyleborus tonkinensis Schedl, 1934 syn. nov.); Euwallacea velatus (Sampson, 1913) (= Xyleborus rudis Eggers, 1930 syn. nov.); Microperus kadoyamaensis (Murayama, 1934) (= Xyleborus pubipennis Schedl, 1974 syn. nov.; =Xyleborus denseseriatus Eggers, 1941 syn. nov.); Stictodex dimidiatus (Eggers, 1927) (=Xyleborus dorsosulcatus Beeson, 1930 syn. nov.); Webbia trigintispinata Sampson, 1922 (= Webbia mucronatus Eggers, 1927 syn. nov.); Xyleborinus artestriatus (Eichhoff, 1878) (= Xyelborus angustior [sic] Eggers, 1925 syn. nov.; = Xyleborus undatus Schedl, 1974 syn. nov.); Xyleborinus exiguus (Walker, 1859) (= Xyleborus diversus Schedl, 1954 syn. nov.); Xyleborus muticus Blandford, 1894 (= Xyleborus conditus Schedl, 1971 syn. nov.; = Xyleborus lignographus Schedl, 1953 syn. nov.). Seven species are removed from synonymy and reinstated as valid species: Anisandrus cristatus (Hagedorn, 1908), Cyclorhipidion tenuigraphum (Schedl, 1953), Diuncus ciliatoformis (Schedl, 1953), Euwallacea gravelyi (Wichmann, 1914), Euwallacea semirudis (Blandford, 1896), Microperus fulvulus (Schedl, 1942), Xyleborinus subspinosus (Eggers, 1930).

Effect of Trap Color on Captures of Bark-and Wood-Boring Beetles (Coleoptera; Buprestidae and Scolytinae) and Associated Predators

Simple Summary

Several wood-associated insects are inadvertently introduced every year within wood-packaging materials used in international trade. These insects can cause impressive economic and ecological damage in the invaded environment. Thus, several countries use traps baited with pheromones and plant volatiles at ports of entry and surrounding natural areas to intercept incoming exotic species soon after their arrival and thereby reduce the likelihood of their establishment. In this study, we investigated the performance of eight trap colors in attracting jewel beetles and bark and ambrosia beetles to test if the trap colors currently used in survey programs worldwide are the most efficient for trapping these potential forest pests. In addition, we tested whether trap colors can be exploited to minimize inadvertent removal of their natural enemies. Our results confirmed that trap color strongly affects trapping performance. Overall, the trap colors currently adopted in most survey programs (i.e., green and black) are efficient only for certain beetle species, therefore there is a clear need to use additional trap colors to increase the range of species that can be effectively attracted. Moreover, we confirmed that many predators exploit the same visual cues as their preys, and thus trap color cannot be used as a variable to minimize bycatch.

Abstract

Traps baited with attractive lures are increasingly used at entry-points and surrounding natural areas to intercept exotic wood-boring beetles accidentally introduced via international trade. Several trapping variables can affect the efficacy of this activity, including trap color. In this study, we tested whether species richness and abundance of jewel beetles (Buprestidae), bark and ambrosia beetles (Scolytinae), and their common predators (i.e., checkered beetles, Cleridae) can be modified using trap colors different to those currently used for surveillance of jewel beetles and bark and ambrosia beetles (i.e., green or black). We show that green and black traps are generally efficient, but also that many flower-visiting or dark-metallic colored jewel beetles and certain bark beetles are more attracted by other colors. In addition, we show that checkered beetles have color preferences similar to those of their Scolytinae preys, which limits using trap color to minimize their inadvertent removal. Overall, this study confirmed that understanding the color perception mechanisms in wood-boring beetles can lead to important improvements in trapping techniques and thereby increase the efficacy of surveillance programs.

Effect of Cleaning Multiple-Funnel Traps on Captures of Bark and Woodboring Beetles in Northeastern United States

Simple Summary

Semiochemical-baited traps are used to survey insect communities and detect invasive species. These traps are left in the field during the growing season where large amounts of pollen and other debris can build up on smooth trapping surfaces. There was a concern this buildup would provide an escape route for some insects and interfere with trapping results. We tested the effects of this pollen buildup on captures of bark and woodboring beetles in northeastern forests in two experiments. While many beetles did not respond to treatments, we found a positive effect of trap cleaning for three bark beetles and one cerambycid species. The response of other species was more nuanced.

Abstract

Two experiments were conducted in mixed hardwood-conifer forests in the northeastern United States to test the effects of cleaning surfactant and non-surfactant treated multiple-funnel traps used to catch bark and woodboring beetles. Large amounts of pollen and other debris often form a crust on the interior of traps (personal observations). Such surface deposits may provide footholds for beetles to escape capture in traps. In one experiment, we tested cleaned surfactant and non-surfactant traps against non-cleaned surfactant and non-surfactant traps. In a second experiment, we tested field cleaning of modified multiple-funnel traps as an alternative to substituting clean traps on each collection visit. There was no effect of surfactant treated traps, cleaned or not, on total beetles or individual bark beetle species captured. However, in situ cleaned traps were statistically better at capturing total beetles, total bark beetles, and several bark beetle species than non-cleaned control traps. Surfactant-treated non-modified traps and cleaned modified traps had higher species richness and abundance than other treatments at the site level. Our results suggest that cleaning traps to remove accumulated pollen and debris may be helpful for some species but would have limited benefit for broad-scale trapping of bark and woodboring beetles in northeastern forests.

Peering into the Cuba phytosanitary black box: An institutional and policy analysis

To mitigate the movement of non-native organisms with trade, phytosanitary systems have been implemented within and between countries. In some countries such as Cuba, little is known about the within-state plant health system. To facilitate the development of future trade partnership between Cuba and the United States, agencies need to understand the organizational structure and diagnostic capacity of the Cuban Plant Protection System, identify potential synergies between the United States and Cuban systems, and identify steps towards cooperation. This paper fills this critical void by presenting a descriptive analysis of the plant health system in Cuba. Information was integrated from available literature, informal interviews with Cuban experts, and workshops focused on Cuban policies, risk, and potential collaboration attended by Cuban and American experts. We identify the next practical steps in improving cooperation, including building trust and capacity. Mutual understanding of phytosanitary systems will be crucial for the regional economic and environmental stability of a post-embargo United States-Cuban relationship.

High efficiency transformation and mutant screening of the laurel wilt pathogen, Raffaelea lauricola

The fungal pathogen, Raffaelea lauricola, is the causative agent of laurel wilt, a devastating disease affecting the Lauraceae family. The fungus is vectored by ambrosia beetles that carry the fungus in specialized structures (mycangia), with the fungus acting as a symbiont and food source for beetle larvae growing in tree galleries. In order to probe the molecular basis for plant pathogenicity and insect symbiosis of the laurel wilt fungus, molecular tools including establishment of efficient transformation protocols are required. Resistance marker profiling revealed susceptibility of R. lauricola to phosphinothricin, chlorimuron ethyl, hygromycin, and benomyl. Agrobacterium-mediated transformation using either the bar or sur marker resulted in 1-200 transformants/10⁵ spores. A second protocol using lithium acetate-polyethylene glycol (LiAc-PEG) treatment of fungal blastospores yielded 5-60 transformants/μg DNA/10⁸ cells. Transformants were mitotically stable (at least 5 generations), and > 95% of transformants showed a single integration event. R. lauricola strains expressing green and red fluorescent proteins (EGFP and RFP), as well as glucuronidase (GUS), were constructed. Using the Agrobacterium-mediated method, a random T-DNA insertion library was constructed, and genetic screens led to the isolation of developmental mutants as well as mutants displaying enhanced resistance to sodium dodecyl sulfate (SDS) or fluconazole, and those showing decreased susceptibility to biphenol. These results establish simple and reliable genetic tools for transformation of R. lauricola needed for genetic dissection of the symbiotic and virulent lifestyles exhibited by this fungus and establish a library of insertion mutants that can be used in various genetic screens to dissect molecular pathways. KEY POINTS: • Vectors and transformation protocols were developed for Raffaelea lauricola. • Method was used for construction of a random insertion mutant library. • Mutant library was validated by phenotypic screens for resistance and susceptibility to various agents.

New Coleoptera records from eastern Canada, with additions to the fauna of Manitoba, British Columbia, and Yukon Territory

One-hundred-eleven new provincial and territorial Coleoptera records are reported from New Brunswick (64), Nova Scotia (20), Prince Edward Island (5), Quebec (14), Manitoba (3), British Columbia (3), and Yukon Territory (2) for the 26 following families: Carabidae, Dytiscidae, Histeridae, Staphylinidae, Scarabaeidae, Buprestidae, Eucnemidae, Elateridae, Cantharidae, Erotylidae, Monotomidae, Cryptophagidae, Passandridae (first record of this family from New Brunswick), Laemophloeidae, Nitidulidae, Anamorphidae, Coccinellidae, Latridiidae, Mordellidae, Tenebrionidae, Cerambycidae, Chrysomelidae, Anthribidae, Brentidae, Dryophthoridae, and Curculionidae. Among these are ten new Canadian records: Heterosternuta oppositus (Say, 1823) (Dytiscidae) (New Brunswick), Gyrophaena blatchleyi Seevers, 1951 (Staphylinidae) (Quebec), Acropteroxys lecontei Crotch, 1873 (Erotylidae) (Manitoba), Placonotus falinorum Thomas, 2011 (Laemophloeidae) (Quebec), Adelina pallida (Say, 1824) (Tenebrionidae) (Quebec), Poecilocera harrisii (J.L. LeConte, 1851) (Chrysomelidae) (New Brunswick), Plesiobaris albilata (LeConte, 1876) (Curculionidae) (Quebec, New Brunswick), Pseudopityophthorus asperulus (LeConte, 1868) (Curculionidae) (Nova Scotia), Hylurgops palliatus (Gyllenhal, 1813) (Curculionidae) (New Brunswick), and Heteroborips seriatus (Blandford, 1894) (Curculionidae) (Nova Scotia). Plesiobaris disjuncta Casey reported as new for Canada in New Brunswick and Quebec by Webster et al. (2012a) is actually P. albilata (LeConte) and thus P. disjuncta is removed from the faunal list of Canada. Eleven species from New Brunswick not previously reported in literature were found on the online platforms BugGuide.Net and iNaturalist and are reported in this publication. This highlights the importance of online platforms dedicated to recording wildlife observations and citizen science in detecting new species records. Data is also presented for seven species from Quebec and two species from New Brunswick reported by Bousquet et al. (2013) without any supporting information for their occurrence in these provinces. Among the species reported here, 32 are adventive.

Trap Height Affects Catches of Bark and Woodboring Beetles (Coleoptera: Curculionidae, Cerambycidae) in Baited Multiple-Funnel Traps in Southeastern United States

In north-central Georgia, trap height affected catches of some species of bark and woodboring beetles (Coleoptera) in traps baited with lures used in surveillance programs to detect non-native forest insects. Traps were placed within the canopy and understory of mature oak trees (Quercus spp.) with collection cups placed 18-23 m above ground level (AGL), and 0.3-0.5 m AGL, respectively. Traps were baited with ethanol to target ambrosia beetles (Curculionidae: Scolytinae) in one experiment, ethanol + syn-2,3-hexanediol + racemic 3-hydroxyhexan-2-one + racemic 3-hydroxyoctan-2-one to target hardwood woodborers (Cerambycidae) in a second experiment, and α-pinene + racemic ipsenol + racemic ipsdienol to target pine bark beetles (Curculionidae) and woodborers (Cerambycidae) in a third experiment. Canopy traps were more effective than understory traps for detecting Cnestus mutilatus (Blandford) (Curculionidae), Neoclytus scutellaris (Olivier), and Monochamus titillator (F.) (Cerambycidae). The reverse was true for Xylosandrus crassiusculus (Motschulsky), Dendroctonus terebrans (Olivier) (Curculionidae), and Neoclytus acuminatus (F.) (Cerambycidae). Catches of a third group which included Hylobius pales (Herbst), Ips grandicollis (Eichhoff) (Curculionidae), Neoclytus mucronatus (F.), and Anelaphus pumilus (Newman) (Cerambycidae) were largely unaffected by trap height. Similar patterns were noted for species of Cleridae, Scarabaeidae, Trogossitidae, and Zopheridae but not Histeridae or Tenebrionidae (Coleoptera). Catches of the bee assassin Apiomerus crassipes (F.) (Hemiptera: Reduviidae) in traps baited with the hardwood borer blend were greater in canopy traps than in understory traps.

Acquisition of fungi from the environment modifies ambrosia beetle mycobiome during invasion

Microbial symbionts can play critical roles when their host attempts to colonize a new habitat. The lack of symbiont adaptation can in fact hinder the invasion process of their host. This scenario could change if the exotic species are able to acquire microorganisms from the invaded environment. Understanding the ecological factors that influence the take-up of new microorganisms is thus essential to clarify the mechanisms behind biological invasions. In this study, we tested whether different forest habitats influence the structure of the fungal communities associated with ambrosia beetles. We collected individuals of the most widespread exotic (Xylosandrus germanus) and native (Xyleborinus saxesenii) ambrosia beetle species in Europe in several old-growth and restored forests. We characterized the fungal communities associated with both species via metabarcoding. We showed that forest habitat shaped the community of fungi associated with both species, but the effect was stronger for the exotic X. germanus. Our results support the hypothesis that the direct contact with the mycobiome of the invaded environment might lead an exotic species to acquire native fungi. This process is likely favored by the occurrence of a bottleneck effect at the mycobiome level and/or the disruption of the mechanisms sustaining co-evolved insect-fungi symbiosis. Our study contributes to the understanding of the factors affecting insect-microbes interactions, helping to clarify the mechanisms behind biological invasions.