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As part of a long-term project on unraveling the use of pheromones in the large beetle family Cerambycidae, field trials were conducted with generic blends of known cerambycid pheromones at a desert site in southern California. In the first year of testing (2022), the species Eustromula valida (LeConte) (subfamily Cerambycinae, tribe Elaphidiini) and Aethecerinus latecinctus (Horn) (Cerambycinae, Trachyderini) were weakly attracted to one of the lure blends. In follow-up trials in 2023, only E. valida were caught, and collection of volatiles from both sexes of E. valida determined that males sex-specifically produced 3-methylthiopropan-1-ol (methionol), a compound that was not in the tested lure blends. Beetles of both sexes were strongly and specifically attracted to this compound in field bioassays, verifying that it is an aggregation-sex pheromone. No sympatric species were attracted to methionol while it was deployed in the field. Several recent studies have identified methionol as a pheromone component for other cerambycid species in both North and South America, suggesting it may represent another common pheromone component within the Cerambycidae. [ABSTRACT FROM AUTHOR]

Glycobius speciosus (Say) was studied in New York State to elucidate poorly known aspects of its biology. Head capsule size from excavated larvae coupled with gallery lengths measured at the time of excavation was used to characterize larval development. Partial life tables indicated nearly 20% of G. speciosus survive to adulthood. Larvae experienced 30% of their mortality during early development, 27% during mid-larval development, and 43% during late larval development. Predation by hairy woodpeckers, Dryobates villosus (Linnaeus) (Piciformes: Picidae), the only unambiguous source of mortality, accounted for 43% mortality in naturally infested trees located and followed 2004–2009, and 74% late instar mortality. One parasitoid, Dolichomitus irritator (Fabricius) (Hymenoptera: Ichneumonidae), was recovered from a single larva. Beetles emerged between 316 accumulated DD (base 10 °C) and 648 DD. Males emerged prior to, or simultaneously with, females and lived longer. Female fecundity averaged 41.3 ± 6 eggs. Larval eclosion occurred 7–10 days after oviposition. Non-functional ovipositors observed in 16% of females represented an appreciable reproductive loss. In 77% of infested trees 1 oviposition site was located and in 70% of oviposition sites examined only 1 or 2 larvae successfully eclosed, penetrated the bark to the phloem-xylem interface, and began feeding. Beetles preferred southern and eastern aspects for oviposition which occurred preferentially on the lower bole (<20 cm). Male beetles had longer and wider antennae than females, pronotal pits containing gland pores, and a straight to concave posterior margin of the terminal sternite compared to the more rounded margin of females. [ABSTRACT FROM AUTHOR]

Invasive insect wood borers are a threat to global forests and tree-related industries as they can damage trees and spread plant pathogens. Reports of damages by wood borers on plants that were planted overseas may facilitate the identification of potential invaders and speed up risk assessment. However, much of this information remains unavailable to the international plant protection community due to language barriers, lack of digitization, or limited circulation of regional literature. Here, we investigated reports of wood borers on 7 important North American commercial tree species planted in China (Carya illinoinensis , Liquidambar styraciflua , Pinus elliottii , Pinus taeda , Quercus texana , Quercus rubra , and Quercus virginiana) in peer-reviewed as well as "grey" (nonpeer-reviewed) Chinese literature. A total of 60 unique wood borer records were found, yielding reports of 4 orders, 39 genera, and 44 species of insect wood borers. Among Coleoptera, longhorned beetles (Cerambycidae) were the most commonly reported colonizers of North American trees in China. Chinese peer-reviewed reports of pests on alien plants are a valuable tool to survey for potential wood-boring invaders of North America, and wherever North American trees are planted and have the potential to encounter Asian invasive insects. Digitization and dissemination of non-English literature are essential for contemporary risk assessment. On the other hand, the nonpeer reviewed "grey" literature, primarily agency reports and student theses, provided only 5% of the records; many incidental observations were unreliable. [ABSTRACT FROM AUTHOR]

In 2011–2013, we determined the interactive effects of the cerambycid pheromones racemic syn -2,3-hexanediol, racemic 3-hydroxyhexan-2-one, and racemic 3-hydroxyoctan-2-one on trap catches of predators associated with bark and woodboring beetles in north Georgia and South Carolina. Temnoscheila virescens (F.) (Coleoptera: Trogossitidae) was attracted to traps baited with 3-hydroxyhexan-2-one; ethanol enhanced attraction. Traps baited with syn -2,3-hexanediol attracted Chariessa pilosa (Forster) (Coleoptera: Cleridae); attraction was interrupted by 3-hydroxyhexan-2-one. An assassin bug Apiomerus crassipes (F.) (Hemiptera: Reduviidae) was attracted to traps baited with 3-hydroxyhexan-2-one and/or 3-hydroxyoctan-2-one. Ethanol had no effect on trap catches of C. pilosa and A. crassipes. We compared response profiles of these predators to those of longhorn beetles captured in these same studies to provide insights on possible ecological interactions between these species. [ABSTRACT FROM AUTHOR]

Knowledge of a species' phenology can assist with timing accurate surveys to detect presence and density in a novel environment. Trichoferus campestris (Faldermann) (Coleoptera: Cerambycidae) has been found in the United States since the 1990s, but its biology and behavior remain poorly understood. This study investigated the phenology of T. campestris in Minneapolis and St. Paul, Minnesota, USA, based on local temperature data. In the summers of 2019 and 2020, 30 and 40 pheromone-baited traps, respectively, were deployed in trees in suburban parks to monitor capture of local individuals. Traps were suspended from branches of mature trees selected at random, with nine genera of trees selected over both years. Early, peak, and late adult abundance were characterized, and the impact of tree genus in which each trap was hung was evaluated. Abundance was found to be unimodal both summers with a peak around 650 degree days (base 10°C) in early July. Significantly more adult T. campestris were caught in traps hung in trees of the genus Tilia than in trees of the genus Quercus. These findings are important first steps to improving monitoring of T. campestris presence and conducting risk assessments. [ABSTRACT FROM AUTHOR]

Anoplophora chinensis (Forster) is a xylophagous invasive cerambycid whose larvae feed on the lower bole and exposed roots of many tree species in orchard, urban, and forested habitats. Larval survival and development of A. chinensis from Italy and China were evaluated at eight constant temperatures (5, 10, 15, 20, 25, 30, 35, and 40°C). Development was slow or did not occur at temperatures ≤10 and >35°C. The TMin for the first six instars and the pupa was <10°C, while TMin for the higher instars was closer to 12°C. The ultimate instar for both populations was insensitive to temperature. When the TMax thresholds could be estimated they were between 31 and 41°C. Temperature also influenced larval weight gain; larvae held at 25–30°C generally weighed the most from the fourth instar on. The number of degree days for 50% of the population to molt to the next instar increased with increasing instar for both populations up through the sixth instar. Anoplophora chinensis may use wood moisture content in conjunction with temperature as a cue as to when to pupate. These responses of A. chinensis to temperature can be used for developing phenological models to predict timing of stages for management or eradication efforts. [ABSTRACT FROM AUTHOR]

In 2016, we conducted three experiments to clarify the effects of 2,3-hexanediols isomers on trap catches of Neoclytus acuminatus (F.) (Coleoptera: Cerambycidae). We also noted the effects of the isomers on trap catches of other cerambycids and associated species of predators and competitors. Catches of N. acuminatus in traps baited with ethanol + syn -2,3-hexanediol + racemic 3-hydroxyoctan-2-one were reduced with the addition of anti -2,3-hexanediol, an attractant for Curius dentatus Newman (Coleoptera: Cerambycidae). A fourth experiment conducted in 2017 verified that racemic 3-hydroxyoctan-2-one increases catches of N. acuminatus in traps baited with ethanol + syn -2,3-hexanediol. The addition of anti- 2,3-hexanediol increased catches of Knulliana cincta (Drury) (Coleoptera: Cerambycidae) in traps baited with ethanol + racemic 3-hydroxyoctan-2-one, whereas attraction of Neoclytus scutellaris (Olivier) to traps baited with ethanol + racemic 3-hydroxyhexan-2-one was reduced by syn -2,3-hexanediol. Trap catches of the beetle predators Chariessa pilosa (Forster), Enoclerus ichneumonus (F.), and Madoniella dislocata (Say) (Coleoptera: Cleridae) were affected by 2,3-hexanediol isomers, whereas other common predators were unaffected by the isomers. Attraction of the bostrichid Xylobiops basilaris (Say) (Coleoptera: Bostrichidae) was increased by the 2,3-hexanediols; the relative effect of the two isomeric blends was dependent on trap co-baits of 3-hydroxy-2-ketones. The two enantiomeric blends of 2,3-hexanediol had minimal effects on catches of most species of ambrosia beetles, whereas the 3-hydroxy-2-ketones affected trap catches of some species. [ABSTRACT FROM AUTHOR]

Woody debris left after timber harvest may be used to produce bioenergy. This will help reduce reliance on nonrenewable fossil fuels. There are ecological impacts to the use of this woody material as many species use coarse woody debris for food and shelter. An understanding of how the removal of woody biomass after forest harvest changes the functional diversity of forest communities is needed to make sustainable management decisions. Many longhorned beetles (Coleoptera: Cerambycidae) provide ecosystem services by reducing woody debris in forests and pollinating flowering plants including trees. I used a taxonomically and functionally diverse community of longhorned beetles to examine changes to functional diversity following different levels of biomass removal in a secondary forest in south-central Indiana, USA.The functional diversity was measured prior to forest harvest and biomass removal and for 2 yr after treatment. I predicted that the abundance and functional group richness of the longhorned beetles would correlate positively with the volume of woody biomass left on the site, and that the community would show resilience by returning to the functional portfolio that was in place in the pre-harvest communities and occurred in the control. The abundance and functional group richness increased with more woody debris left on site.There was much variance in the trajectory of the community following harvest, with no clear trend toward pre-harvest functional portfolio that would indicate resilience. A 3-yr study is likely not long enough to capture this resilience, especially on sensitive sites. [ABSTRACT FROM AUTHOR]

An increasing body of evidence indicates that cerambycid beetles native to different continents may share pheromone components, suggesting that these compounds arose as pheromone components early in the evolution of the family. Here, we describe the identification and field testing of the pheromone blends of two species in the subfamily Cerambycinae that share 2-nonanone as an important component of their male-produced aggregation-sex pheromones, the South American Stizocera consobrina Gounelle (tribe Elaphidiini) and the North American Heterachthes quadrimaculatus Haldeman (tribe Neoibidionini). Along with 2-nonanone, males of S. consobrina also produce 1-(1 H -pyrrol-2-yl)-1,2-propanedione, whereas males of H. quadrimaculatus produce 10-methyldodecanol. Field bioassays conducted in Brazil (targeting S. consobrina) and Illinois (targeting H. quadrimaculatus) demonstrated that adults of both species were attracted only by the blends of both their pheromone components, and not to the individual components. The use of the pyrrole as a critical component for the former species is further evidence that this compound is a common pheromone structure among cerambycines in different biogeographical regions of the world. [ABSTRACT FROM AUTHOR]

Research over the last 15 yr has shown widespread pheromone parsimony within the coleopteran family Cerambycidae, with a number of highly conserved pheromone motifs, often shared within and across subfamilies, tribes, and genera. Our goals were to increase our understanding of the evolution of volatile pheromones within the Cerambycidae, their role in reproductive isolation and to identify pheromones for use in the development of lures for monitoring cerambycids. Over 3 yr, we tested 12 compounds known to be cerambycid pheromones as possible attractants at sites across Idaho. This study focused on species within the cerambycine genus Phymatodes (Tribe: Callidiini). We also collected and analyzed headspace volatiles of captured Phymatodes dimidiatus (Kirby). Our results demonstrate that (R)-2-methylbutan-1-ol is a male-produced volatile pheromone for P. dimidiatus. These results are consistent with prior research suggesting that (R)-2-methylbutan-1-ol and (R)-3-hydroxyhexan-2-one, individually or in a blend of both compounds, commonly serve as pheromones for Phymatodes spp. We captured Phymatodes starting in mid-May, continuing through mid-August. Our data indicate that flight periods of Phymatodes spp. in Idaho overlap. These species may be utilizing various mechanisms to ensure reproductive isolation, such as the production of different volatile pheromones, minor components, and/or proportions of components, utilizing different host species and/or host volatiles, differing daily activity periods, and/or occupying different heights in the tree canopy. Our results contribute to the basic understanding of the chemical and behavioral ecology of the Cerambycidae and can be applied to the development of pheromone lures for monitoring of economically important or endangered species. [ABSTRACT FROM AUTHOR]

Ontsira mellipes Ashmead is a gregarious larval ectoparasitoid of woodboring cerambycids. It is native to North America but can readily attack the exotic Asian longhorned beetle, Anoplophora glabripennis (Motschulsky). This study aimed to develop an efficient rearing system for this parasitoid, as a potential novel association biocontrol agent for the beetle, by investigating the effects of different densities of host (two, three, or four larvae) and parasitoid (one, two, three, four, five, six, seven, and eight female wasps) on Ontsira 's parasitization efficiency and reproductive outcomes. Results showed that overall parasitism and total numbers of parasitized hosts or progeny produced increased with host and/or parasitoid densities, but the number of parasitized hosts or progeny produced per female parasitoid decreased with parasitoid density at each given host density. Nonlinear regression indicated a consistent pattern of mutual interference as parasitoid density increased. Additional experiments showed that superparasitism (indirect interference) did not occur probably because the parasitoid detects hosts through vibration cues from host feeding and attacked (thus paralyzed) hosts are no longer detectable. Thus, the interference probably results from direct or exploitative competition. Interestingly, female parasitoids responded to increased parasitoid density with a significant increase in clutch size. Overall, per capita parasitization efficiency or reproductive outcomes were optimized at a low parasitoid–host ratio but with large group size of hosts and parasitoids. Therefore, an optimal combination of exposing three or four parasitoids to four hosts is proposed for efficient mass-rearing of this parasitoid. [ABSTRACT FROM AUTHOR]

In 2014–2019, we conducted six experiments in north-central Georgia in an attempt to verify the aggregation pheromone response of the ambrosia beetle Gnathotrichus materiarius (Fitch) (Coleoptera: Curculionidae: Scolytinae: Scolytini: Corthylina) to sulcatol known to be produced by male G. materiarius ; we failed to catch any G. materiarius. However, we did find that another corthyline ambrosia beetle species Monarthrum mali (Fitch) was attracted to (R)-(–)-sulcatol, whereas the longhorn beetle Leptostylus asperatus (Haldeman) (Coleoptera: Cerambycidae: Lamiinae) was attracted to (S)-(+)-sulcatol. Attraction of both species was unaffected by the respective antipodes. Ethanol enhanced attraction of both species to traps baited with sulcatol. In at least one experiment, attraction to ethanol-baited traps was enhanced by sulcatol for Xylosandrus crassiusculus (Motschulsky), Xyleborus spp., and Hypothenemus spp. but reduced for Cnestus mutilatus (Blandford) (Coleoptera: Curculionidae: Scolytinae). Additionally, traps baited with ethanol and racemic sulcatol [50% (S)-(+): 50% (R)-(-)] caught the greatest numbers of four species of beetle predators: Coptodera aerata Dejean (Coleoptera: Carabidae), Colydium lineola Say (Coleoptera: Zopheridae), Madoniella dislocata (Say), and Pyticeroides laticornis (Say) (Coleoptera: Cleridae). Ethanol but not sulcatol attracted Temnoscheila virescens (F.) (Coleoptera: Trogossitidae). Information on interspecific relationships within forested communities may help us to better determine the roles of these species in maintaining stable and resilient forested ecosystems. [ABSTRACT FROM AUTHOR]

Ropica honesta Pascoe is a small-sized cerambycid that has been recorded in tropical to subtropical Asia. In this study, life-history traits were examined for a local population collected from Iriomote Island (24.3°N, 123.8°E), Okinawa, Japan, by rearing insects on artificial diet as larval food. The egg period was 5.9 ± 0.3 d at 25°C. There was no significant difference in the duration of the larval, pupal, and adult preoviposition periods between long-day (14:10 [L:D]) and short-day (12:12 [L:D]) photoperiods at both 20 and 25°C. These periods at 25°C (14:10 [L:D]) were 28.5 ± 1.4, 8.4 ± 0.5, and 9.6 ± 1.9 d (mean ± SD), respectively. The relationship between the developmental rate and temperature followed the law of total effective temperature; thus, the developmental threshold temperature and thermal constant were estimated based on these data. Together with the finding that R. honesta may not have diapause in the egg stage, it is suggested that this beetle does not have diapause in the life cycle. Furthermore, when larvae were reared on natural food (dead twigs of hardwoods) adults emerged from the twigs 47.6 ± 2.9 d after oviposition, and this value was close to the total duration of the egg to pupal periods. Together with the data for annual temperature of the habitat and the fact that food resources for the species (dead twigs and leaves of hardwoods) are available throughout the year, we conclude that R. honesta develops and reproduces all year round, with five generations at maximum. [ABSTRACT FROM AUTHOR]

During field bioassays in Kenya of 10 chemicals that are common pheromone components of cerambycid beetles, six species in the subfamily Cerambycinae were significantly attracted to 3-hydroxyhexan-2-one, and one species in the subfamily Lamiinae was significantly attracted to 2-(undecyloxy)ethanol (known as monochamol). These results further demonstrate that the former compound is highly conserved as a cerambycid pheromone because it has now been identified or implicated in the pheromones of numerous cerambycine species native to all six habitable continents. Similarly, monochamol has been identified or implicated as a pheromone component for species in the subfamily Lamiinae native to Asia, Europe, North America, and now Africa. The eight other compounds tested, including (E)-6,10-dimethyl-5,9-undecadien-2-ol (fuscumol), the corresponding (E)-6,10-dimethyl-5,9-undecadien-2-yl acetate (fuscumol acetate), syn - and anti -(2,3)-hexanediols and (2,3)-octanediols, 3-hydroxyoctan-2-one, and 3-hydroxydecan-2-one, did not attract significant numbers of any species. [ABSTRACT FROM AUTHOR]

The longhorn beetles play important roles in the forest ecosystem processes and their diversity is affected by many environmental disturbances worldwide. This study aimed at understanding how the structural heterogeneity of the habitat can affect the longhorn beetle assemblage in three areas of an Atlantic Forest, which suffered differential impacts in the past and are now in different successional stages. The area in the most advanced successional stage had mainly lower density of trees, but with greater availability of dead wood, especially larger diameter classes. They are important forest components that contribute to the structural diversity of the habitat providing resources for a variety of dependent species. This area has also shown the greatest richness and abundance of longhorn beetles. Our results suggest that these beetles are closely associated with the structural heterogeneity of forests and can be valuable indicators for assessing biodiversity and quality of forest habitat. It also shows that old-growth forest remnants can be the key to the maintenance of the diversity of the longhorn beetles and, consequently, of the ecosystem services they provide. [ABSTRACT FROM AUTHOR]

We report here the pheromone of Megacyllene antennata (White) (Coleoptera: Cerambycidae), a species native to southwestern North America whose larvae feed in woody tissues of mesquite (Prosopis species; Fabaceae). Adult males sex-specifically produced a blend of eight common natural products, including the monoterpene alcohol (S)-α-terpineol; the monoterpenes (S)-limonene and terpinolene; the aromatic alcohols (R)-1-phenylethanol and 2-phenylethanol; and (E)-2-hexenol, (E)-2-hexenal, and 1-hexanol. Individual males produced the components in varying amounts, but (S)-α-terpineol and (E)-2-hexenal were always present and together constituted the majority of the blend. A synthetic reconstruction of the complete blend attracted both males and females of M. antennata during field bioassays, as did all subsets of the blend that included (S)-α-terpineol and (E)-2-hexenol. Adults were most strongly attracted to blends of the latter two compounds when in ratios approaching parity. Neither of the compounds were present in the bouquet of volatiles emitted by host plants of the larvae. [ABSTRACT FROM AUTHOR]

We describe approaches to addressing the perennial challenge of collecting a sufficient diversity of nontarget insects for host-specificity testing of candidate biocontrol agents of invasive wood-borers such as the Asian longhorned beetle, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae). Multifunnel and intercept traps, retrofitted to maintain live insects and baited with cerambycid-specific pheromone lures, were deployed in diverse forests in southeastern Massachusetts. We collected 1,288 adult beetles comprising 56 species, mostly from the subfamilies targeted by the lures (Cerambycinae and Lamiinae). The type of trap and tree species in which the trap was hung did not seem to affect the species caught. Methods used to induce egg laying and techniques to rear cerambycid larvae are described. Dastarcus helophoroides (Fairmaire) (Coleoptera: Bothrideridae) is the most common Asian longhorned beetle parasitoid in China; therefore, we conducted tests to determine whether cerambycids native to North America would be at risk should this species be released. D. helophoroides attacked all six species tested: Monochamus scutellatus (Say) (Coleoptera: Cerambycidae: Lamiinae), Monochamus notatus (Drury) (Coleoptera: Cerambycidae: Lamiinae), Apriona rugicollis Chevrolat (Coleoptera: Cerambycidae: Lamiinae), Enaphalodes rufulus (Haldeman) (Coleoptera: Cerambycidae: Cerambycinae), Graphisurus fasciatus (DeGeer) (Coleoptera: Cerambycidae: Lamiinae), and Neoclytus acuminatus (F.) (Coleoptera: Cerambycidae: Cerambycinae). Parasitism of native cerambycids was not statistically different from parasitism of Asian longhorned beetle, except for N. acuminatus, which is a considerably smaller species than Asian longhorned beetle, and for M. notatus and M. scutellatus, which attack pine trees rather than hardwood trees like Asian longhorned beetle and the other native species tested. Our testing indicates that many native cerambycids would be vulnerable to D. helophoroides and we conclude that D. helophoroides should not be considered for release as a biocontrol agent in North America. [ABSTRACT FROM AUTHOR]

In field trials testing attraction of cerambycid beetles to a blend of known pheromone components plus host plant volatiles, several species in the subfamily Spondylidinae were attracted to baited traps, suggesting that one or more components of the blend might constitute their pheromones. Here, we describe laboratory and field experiments aimed at identifying the actual pheromone components produced by these species. Analysis of headspace odors collected from male Tetropium abietis (Fall) (Coleoptera: Cerambycidae) contained (S)-fuscumol as a single component, whereas Asemum nitidum (LeConte) (Coleoptera: Cerambycidae) males produced both (S)-fuscumol and geranylacetone, and Asemum caseyi (Linsley) (Coleoptera: Cerambycidae) produced only geranylacetone. In field trials testing fuscumol, fuscumol acetate, and geranylacetone as individual components or in blends, in combination with host plant volatiles, A. nitidum were attracted to blends of fuscumol and geranylacetone, T. abietis were attracted to fuscumol alone, and A. caseyi were attracted to geranylacetone alone. Fuscumol acetate did not appear to be either attractive or inhibitory. These results, along with previous catches of spondylidine species in traps baited with fuscumol, provide evidence that fuscumol and geranylacetone are likely to be relatively common pheromone structures for species in the subfamily Spondylidinae. [ABSTRACT FROM AUTHOR]

The genus Monochamus Dejean (Coleoptera: Cerambycidae) includes large, woodboring, longhorned beetles, which colonize pine trees in North America. Many authors have classified the genus as saprophagous, but one recent study reported successful colonization of standing jack pine trees (Pinus banksiana Lamb.) (Pinales: Pinaceae) following severe wind disturbance in Minnesota. We tested whether two Monochamus species native to the southeastern United States (M. titillator (Fabricius) and M. carolinensis (Olivier)) could successfully colonize healthy shortleaf pines (Pinus echinata Mill.) (Pinales: Pinaceae) in recently harvested stands without coincident abiotic or biotic stressors, such as lightning strikes or bark beetle attacks. We attached commercially available semiochemical lures, including monochamol, ethanol, and ipsenol, to healthy shortleaf pine trees and observed Monochamus spp. oviposition response. Egg development was monitored following oviposition by harvesting attacked trees and dissecting oviposition pits. High numbers of oviposition pits were observed on trees treated with lures containing the bark beetle pheromone ipsenol and pits were highly concentrated on the tree bole near lures. Although egg deposition occurred, pit dissection revealed large amounts of resin present in almost all dissected pits and that egg hatch and subsequent larval development were rare. Our results demonstrate that southeastern Monochamus spp. are unlikely to be primary pests of healthy shortleaf pines due to resinosis. To better understand the host finding behavior of these two Monochamus species, we also conducted trapping trials with several semiochemical combinations. Both species and sexes demonstrated similar attraction to compounds, and the most attractive lure combined host volatiles, pheromone, and sympatric insect kairomone. [ABSTRACT FROM AUTHOR]

The coffee white stemborer, Xylotrechus quadripes Chevrolat (Coleoptera: Cerambycidae), feeds primarily on Coffea arabica L. (Gentianales: Rubiaceae) with its egg, larva, and pupa being developed within the trunk. The detection of chemosensory-related cues linked to adult mating, host seeking, and recognition is driven by three chemoreceptor gene repertoires of odorant (ORs), gustatory (GRs), and ionotropic (IRs) receptors as well as sensory neuron membrane proteins (SNMPs). Yet, information on these genes involved in chemoreception is unavailable in X. quadripes and relatively poor in the cerambycid beetles. Here, we presented the identification of four chemosensory transmembrane proteins from the antennal transcriptome of X. quadripes, including 33 ORs, five GRs, 18 IRs, and four SNMPs. Phylogenetic analysis classified the ORs into groups 1, 2, 3, 7, and olfactory coreceptor (Orco), showing three potential candidates (OR13, OR17, and OR21) for the sensing of male sex pheromones. The IRs were clustered into 10 orthologous groups, with additional copies for IR41a, IR64a, and IR75 clades. Four SNMPs were distributed in four independent clades, possibly representing a complete set in this species. Expression profiles revealed that all the genes were highly expressed in antennae, suggesting their olfactory roles. In addition, most of the genes showed the expression in nonantennal tissues including thoraxes, abdomens, wings, and legs, suggesting their involvement in nonchemosensory functions. Of notice, a highly conserved coreceptor IR25a displayed male-biased expression in the antennae, as the first presence in the cerambycid beetles. This study has established reference resources for understanding the mechanisms underlying the interactions between/within this beetle and its host plants. [ABSTRACT FROM AUTHOR]

Tetropium fuscum (Fabricius) (Coleoptera: Cerambycidae), a phloem-feeding and wood-boring beetle introduced from Eurasia, attacks spruce in eastern Canada alongside its native congener Tetropium cinnamopterum Kirby. We reared phloem- and wood-feeding insects (and their predators) from bolts of red and Norway spruce (Picea rubens and Picea abies) in Nova Scotia, comparing insect communities between bolts with added eggs of T. fuscum or T. cinnamopterum and bolts without added Tetropium (controls). We tested for impacts of each Tetropium on insect community structure (Simpson's diversity, richness, and evenness). We also asked whether, consistent with Darwin's Naturalization Hypothesis, Tetropium spp. would have greater impacts on emergence of its closer relatives (which might be most likely to compete and/or share natural enemies). Addition of Tetropium eggs (either species) to bolts lowered insect diversity in both host trees. Both richness and evenness components of diversity were always lower in +Tetropium treatments, although different components reached statistical significance in different Tetropium species x host combinations. Addition of Tetropium spp. significantly reduced emergence of some species: Evodinus monticola (Randall) (Coleoptera: Cerambycidae) was reduced by T. fuscum on both hosts and by T. cinnamopterum on Norway spruce; Hylobius congener Dalla Torre, Schenkling, and Marshall was reduced by T. fuscum on red spruce; and Xylophagus sp. (Diptera: Xylophagidae) was reduced by T. cinnamopterum on Norway spruce. However, there was no relationship between Tetropium's impact on a community member and their phylogenetic relatedness, and the overall impacts of Tetropium presence were not very different between T. fuscum and T. cinnamopterum. [ABSTRACT FROM AUTHOR]

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Here, we describe a field experiment that tested for attraction of cerambycid beetles to odors from angiosperm hosts, and whether plant volatiles also serve to enhance attraction of beetles to their aggregation-sex pheromones. Traps were baited with a blend of synthesized chemicals that are common pheromone components of species in the subfamilies Cerambycinae and Lamiinae. The source of plant volatiles was chipped wood from trees of three angiosperm species, as well as from one nonhost, gymnosperm species. Bioassays were conducted in wooded areas of east-central Illinois. Traps were baited with the pheromone blend alone, the blend+wood chips from one tree species, wood chips alone, or a solvent control lure. Seven species of cerambycids were significantly attracted to the pheromone blend, with or without wood chips. In two cases, wood chips from angiosperms appeared to enhance attraction to pheromones, whereas they inhibited attraction in another three cases. Pine chips did not strongly influence attraction of any species. Overall, our results suggest that host plant volatiles from wood chips may improve trap catch with synthesized pheromones for some cerambycid species, but the effect is not general, necessitating case-by-case testing to determine how individual target species are affected. [ABSTRACT FROM AUTHOR]

The chemical structures of aggregation-sex pheromones of longhorned beetles (Coleoptera: Cerambycidae) are often conserved among closely related taxa. In the subfamily Lamiinae, adult males and females of several species are attracted by racemic blends of (E)-6,10-dimethyl-5,9-undecadien-2-ol (termed fuscumol) and the structurally related (E)-6,10-dimethyl-5,9-undecadien-2-yl acetate (fuscumol acetate). Both compounds have a chiral center, so each can exist in two enantiomeric forms. Males of many species of longhorned beetles only produce one stereoisomer of each pheromone component, and attraction may be reduced by the presence of stereoisomers that are not produced by a particular species. In a previous publication, analysis of headspace volatiles of adult beetles of the lamiine species Astyleiopus variegatus (Haldeman) revealed that males sex-specifically produced (S)-fuscumol and (S)-fuscumol acetate. Here, we describe field trials which tested attraction of this species to single enantiomers of fuscumol and fuscumol acetate, or to blends of enantiomers. We confirmed attraction of A. variegatus to its species-specific blend, but during the course of the trials, found that several other species also were attracted. These included Aegomorphus modestus (Gyllenhall), attracted to (S)-fuscumol acetate; Astylidius parvus (LeConte), attracted to (R)-fuscumol; Astylopsis macula (Say), attracted to (S)-fuscumol; and Graphisurus fasciatus (DeGeer), attracted to a blend of (R)-fuscumol and (R)-fuscumol acetate. These results suggest that chirality may be important in the pheromone chemistry of lamiines, and that specific stereoisomers or mixtures of stereoisomers are likely produced by each species. [ABSTRACT FROM AUTHOR]

Recent research has shown that several species in the genus Monochamus, including Monochamus scutellatus scutellatus (Say) and Monochamus notatus (Drury), a close congener, are attracted to an aggregation pheromone, monochamol, but only M. s. scutellatus produces it. Investigations were conducted to determine if there is a diel rhythm in production of monochamol or response to monochamol + host attractants in field trials by M. s. scutellatus and M. notatus to prevent cross attraction with each other. Volatiles were collected from males and females of M. s. scutellatus and M. notatus every 8 h and analyzed by coupled gas chromatography-mass spectrometry. Traps baited with monochamol and the host volatiles α-pinene and ethanol were checked every 8 h in field tests. Only male M. s. scutellatus produced the pheromone, and did so in similar quantities during each 8-h time interval assessed, suggesting there is no diel rhythm in pheromone production. In field tests conducted in early to mid-July, significantly more M. s. scutellatus were captured during morning hours, and significantly more M. notatus were caught during afternoon or early evening hours, suggesting temporal partitioning of flight or in their response to the pheromone lures when both species are present. A temporal switch occurred later in the seasonal flight period (mid-August) when densities of M. s. scutellatus were low; all M. notatus and only one M. s. scutellatus were caught during morning hours. This suggests a temporal separation in mate location behavior when both species are abundant and using the same host to avoid interspecific mating. [ABSTRACT FROM AUTHOR]

We examined the native community of insects interacting with an invasive species, Tetropium fuscum (F.) (Coleoptera: Cerambycidae), in its new range to explore reasons for the invader's relatively slow spread. Tetropium fuscum is a European spruce borer established in Nova Scotia since at least 1990, but it has spread only about 125km from its site of introduction. We compared the densities of Tetropium spp., their known parasitoids, and the community of wood-boring insects at sites located within the invasion zone in Nova Scotia versus well outside this zone, in New Brunswick, Canada. Using red spruce trees stressed by girdling or felling, we tested whether: 1) T. fuscum had altered the native wood-boring community; 2) T. fuscum displaced a native congener, Tetropium cinnamopterum (Kirby); and 3) parasitism rates of Tetropium spp. differed between the invaded and noninvaded zones. Both Tetropium spp. and their parasitoid wasps emerged exclusively from felled trees as opposed to girdled trees. We found no difference in community diversity inside versus outside the invasion zone. The combined densities of both Tetropium spp. and their overall parasitism rates also did not differ between zones, but T. cinnamopterum density was significantly greater outside the invasion zone, suggesting T. fuscum may displace the native congener where they are sympatric. Our results suggest that the native and invasive Tetropium spp. act as a single functional species in the invasion zone. We speculate that natural control agents (predators, parasitoids, and competitors) might be limiting the rate of spread of T. fuscum. [ABSTRACT FROM AUTHOR]

During field screening trials of a number of known cerambycid pheromones in China, males of Megopis costipennis (White) (Coleoptera: Cerambycidae: Prioninae: Callipogonini) were found to be specifically attracted to racemic anti-2,3-octanediol, suggesting that one of the enantiomers of this compound might be a female-produced sex pheromone of this species. Analysis of volatiles produced by beetles of both sexes confirmed this hypothesis: females produced (2R,3S)-2,3-octanediol, whereas males did not, and in coupled gas chromatography-electroantennogram detection analyses, antennae from male beetles responded strongly to this compound. In field trials, males were equally attracted to traps baited with either (2R,3S)-2,3-octanediol or racemic anti-2,3-octanediol, indicating that the enantiomeric (2S,3R)-2,3-octanediol does not antagonize attraction to the naturally produced enantiomer. Thus, the more economical racemic anti-2,3-octanediol can be used for trap baits for this species. Homologous 2,3-hexanediols previously had been identified as sex pheromones or sex attractants of prionine species in the genus Tragosoma Audinet-Serville of the tribe Meroscelisini. [ABSTRACT FROM AUTHOR]

The invasive Asian cerambycid beetle Callidiellum rufipenne (Motschulsky), informally known as the Japanese cedar longhorned beetle, was first detected in North America in North Carolina in 1997. The beetle has since been detected in neighboring states and is expected to further expand its range. However, delineating the current distribution of C. rufipenne has been hindered by the lack of efficient sampling methods. Here, we present the results of research on the chemistry of volatile pheromones of C. rufipenne. Analyses of headspace odors revealed that males produce (R)-3-hydroxyhexan-2-one, with lesser amounts of (S)-3-hydroxyhexan-2-one, and (R)- and (S)-2-hydroxyhexan-3-one. In field bioassays conducted over several years in Connecticut, where populations of the beetle were well established, no reconstructed blend of these compounds was significantly attractive to beetles of either sex. However, during field trials in Japan that targeted another species, we discovered that adult male and female C. rufipenne were attracted to a blend of racemic 3-hydroxyhexan-2-one and a novel natural product, 1-(1H-pyrrol-2-yl)-1,2-propanedione. Attraction to (R)-3-hydroxyhexan-2-one and the pyrrole subsequently was confirmed in field trials in Connecticut. Although it is unclear why the pyrrole acts as a synergist for a species that apparently does not produce it, the serendipitous discovery that adult C. rufipenne are attracted by the blend of ketone and pyrrole provides a badly needed method for monitoring its ongoing range expansion within North America, and for detecting new introductions in other parts of the world. [ABSTRACT FROM AUTHOR]

Insects are unable to synthesize essential amino acids (EAAs) de novo, thus rely on dietary or symbiotic sources for them. Wood is a poor resource of nitrogen in general, and EAAs in particular. In this study, we investigated whether gut microbiota of the Asian longhorned beetle, Anoplophora glabripennis (Motschulsky), a cerambycid that feeds in the heartwood of healthy host trees, serve as sources of EAAs to their host under different dietary conditions. δ13C-stable isotope analyses revealed significant δ13C-enrichment (3.460.1%; mean6SEM) across five EAAs in wood-fed larvae relative to their woody diet. δ13C values for the consumers greater than 1% indicate significant contributions from non-dietary EAA sources (symbionts in this case). In contrast, δ13C-enrichment of artificial diet-fed larvae (controls) relative to their food source was markedly less (1.7±0.1%) than was observed in wood-fed larvae, yet still exceeded the threshold of 1%. A predictive model based on δ13CEAA signatures of five EAAs from representative bacterial, fungal, and plant samples identified symbiotic bacteria and fungi as the likely supplementary sources of EAA in wood-fed larvae. Using the same model, but with an artificial diet as the dietary source, we identified minor supplementary bacterial sources of EAA in artificial diet-fed larvae. This study highlights how microbes associated with A. glabripennis can serve as a source of EAAs when fed on nutrient-limited diets, potentially circumventing the dietary limitations of feeding on woody substrates. [ABSTRACT FROM AUTHOR]

The cerambycid beetle, Phoracantha semipunctata F., was introduced into California in the mid-1980s and killed large numbers of Eucalyptus host trees. The populations of the borer declined to very low levels in the mid-1990s following the establishment of the congener, Phoracantha recurva Newman, and the intentional introduction of the egg parasitoid, Avetianella longoi Siscaro. The distributions of the beetles overlap in the Australian native range, but one species has replaced the other in the adventive range in California. One possible explanation is differential susceptibility to natural enemies introduced for biological control. An alternative explanation for the reduced abundance of P. semipunctata is asymmetric interspecific competition between the two species. To test this hypothesis, equal larval densities of each species were introduced into host logs. In all cases, more P. recurva adults emerged than P. semipunctata adults, but the presence of congeners did not have a different effect than the presence of an equal density of conspecific individuals. Neither the temporal order of introduction or bark thickness altered the outcome of potential competitive interactions. Consequently, it appears that the ecological replacement of one borer with another in the adventive environment in southern California may not be a result of bottom-up intraguild competitive interactions. The top-down effects of natural enemies on P. semipunctata have most likely led to its decline. [ABSTRACT FROM AUTHOR]

A study using Metarhizium brunneum Petch fungal bands designed to improve delivery of conidia to adult Asian longhorned beetles, Anoplophora glabri pennis (Motschulsky), was conducted to determine how a time delay between exposure to infective conidia and pairing of male and female beetles would affect the ability to successfully transfer lethal doses of conidia to a mate. We measured conidial load at the time of mate pairing (0, 4, 24, 48 h postexposure) and assessed its effect on beetle mortality. Conidial load per beetle decreased across the four sampling times, and there was no effect of beetle sex on conidial load. At all time periods postexposure, beetles that climbed across fungal bands carried enough conidia that at least some of their indirectly exposed mates died of mycosis. For indirectly exposed beetles, mortality decreased significantly as the time delay increased from0 to 48 h, and this was independent of beetle sex. Median survival time was only 11.5 d for females indirectly exposed immediately after their mate had been exposed, but >3wk when there was a 48-h delay before pairing. Generally, beetles exposed directly to fungal bands died faster than their indirectly exposed mates. In contrast to the pattern seen for indirectly exposed beetles, beetles exposed directly to fungal bands showed no change in survival times with a delay between exposure and pairing. Median survival times of exposed females and males were generally similar, at 10.5-12.5 d. [ABSTRACT FROM AUTHOR]

The Asian longhorned beetle, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), is distributed widely in China, where it causes severe damage to forests, and is a quarantine pest in Europe, the United States, and Canada. A. glabripennis overwinters as dormant larvae to avoid adverse environmental conditions. To elucidate the cold hardiness of A. glabripennis larvae, the supercooling point (SCP), freezing point (FP), and cold hardiness-related compounds were examined in overwintering larva from five populations in China (Yili, Yanchi, Wulateqianqi, Beijing, and Dezhou). The results showed that the SCP and FP differed significantly among populations, where the SCP of larvae in the Wulateqianqi population was the lowest and highest in the Beijing population. The water, fat, and glycogen contents also differed significantly among the five populations. The SCPs of larvae from all five populations were proportional to glycogen contents, but had no association with water contents and fat contents. The total contents of seven low-molecular weight compounds (glycerol, galactose, glucose, mannose, sorbitol, inositol, and trehalose) differed significantly among populations. Thus, A. glabripennis larvae from different geographical populations contained different sugars or sugar alcohols (especially glycerol, glucose, sorbitol, and trehalose), which helped them to resist cold temperatures. This study provides basic information about that may facilitate the prediction of distribution range expansions and ensure proper implementation of the integrated management of A. glabripennis populations. [ABSTRACT FROM AUTHOR]

Xylophagous insects often thrive on nutritionally suboptimal diets through symbiotic associations with microbes that supplement their nutritional requirements, particularly nitrogen. The wood-feeding cerambycid Anoplophora glabripennis (Motschulsky) feeds on living, healthy host trees and harbors a diverse gut microbial community. We investigated gut microbial contributions to larval nitrogen requirements through nitrogen fixing and recycling (urea hydrolysis) processes, using a combination of molecular, biochemical, and stable isotope approaches. Genes and transcripts of conserved regions of the urease operon ( ureC) and nitrogen fixing ( nif) regulon ( nifH) were detected in A. glabripennis eggs and larvae from naturally infested logs and from larvae reared on artificial diet. Significant nitrogen fixation and recycling were documented in larvae using 15N2 gas and 15N-urea, respectively. Subsequent 15N-routing of incorporated recycled nitrogen into larval essential and nonessential amino acids was shown for 15N-urea diet-fed larvae. Results from this study show significant gut microbial contributions to this insect's metabolic nitrogen utilization through nitrogenous waste product recycling and nitrogen fixation. [ABSTRACT FROM AUTHOR]

Phoracantha longicorn beetles are endemic to Australia, and some species have become significant pests of eucalypts worldwide, yet little is known about their host plant interactions and factors influencing tree susceptibility in Australia. Here, we investigate the host relationships of Phoracantha solida (Blackburn, 1894) on four eucalypt taxa (one pure species and three hybrid families), examining feeding site physical characteristics including phloem thickness, density, and moisture content, and host tree factors such as diameter, height, growth, taper, and survival. We also determine the cardinal and vertical (within-tree) and horizontal (between-tree) spatial distribution of borers. Fewer than 10% of P. solida attacks were recorded from the pure species (Corymbia citriodora subsp. variegate (Hook)), and this taxon also showed the highest survival, phloem thickness, relative growth rate, and bark:wood area. For the two most susceptible taxa, borer severity was negatively correlated with moisture content, and positively related to phloem density. Borers were nonrandomly and nonuniformly distributed within trees, and were statistically aggregated in 32% of plots. More attacks were situated on the northern side of the tree than the other aspects, and most larvae fed within the lower 50 cm of the bole, with attack height positively correlated with severity. Trees with borers had more dead neighbors, and more bored neighbors, than trees without borers, while within plots, borer incidence and severity were positively correlated. Because the more susceptible taxa overlapped with less susceptible taxa for several physical tree factors, the role of primary and secondary chemistries in determining host suitability needs to be investigated. Nevertheless, taxon, moisture content, phloem density, tree size, and mortality of neighboring trees appeared the most important physical characteristics influencing host suitability for P. solida at this site. [ABSTRACT FROM AUTHOR]

After fire, the whitespotted sawyer, Monochamus scutellatus scutellatus (Say) (Coleoptera: Cerambycidae), is considered one of the most damaging xylophagous insects by forest industries in the eastern boreal forest of North America. Although this species is often considered opportunistic because it dwells on various stressed host trees, it can be found in very high abundance after forest fire and, consequently, it has been suspected of being a pyrophilous species or fire-associated species. The aim of this study was first to determine whether the whitespotted sawyer lays eggs preferentially on burned rather than unburned hosts, and second, to determine its preference between black spruce (Picea mariana [Mill.] B.S.P.) and jack pine (Pinus banksiana Lamb.) for oviposition. Host suitability also was estimated to determine if whitespotted sawyer females make optimal choices to maximize offspring development. To determine host suitability, we used the abundance distribution of larval instars as a proxy of larval development quickness and we compared weight and head-capsule width of larvae of different larval instars as measures of insect growth in each type of log. Based on the frequency of oviposition behavior, females showed no preference for either burned or unburned black spruce logs, and both were equally suitable for larval development. Furthermore, females laid more eggs on black spruce than on jack pine, but host suitability was not statistically affected. Nevertheless, larvae had mostly reached the fourth instar on black spruce, whereas those on jack pine were mostly at the third instar, suggesting faster development on black spruce. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Entomology is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Anoplophora glabripennis (Motschulsky) is an introduced invasive pest with the po¬tential to devastate hardwood forests in North America. Using artificial pupal chambers, we documented the time required by teneral adults at three temperatures (20,25, and 30°C), 60 - 80% RH, and a photoperiod of 16:8 (L:D) h to initiate boring after eclosion and subsequently bore completely through a 7-mm (range, 3-11 mm) layer of Norway maple wood (Acer platanoides L.). In total, 218 laboratory-reared pupae from the Chicago, IL, or Inner Mongolia, China, populations were used in the study. Females (1.54 ± 0.03 g) weighed significantly more than males (1.12 ± 0.03 g), but the average weights of the beetles emerging in each temperature did not differ. Adult weight was positively correlated with exit hole diameter (diameter [mm] = 2.2* weight [g] + 7.9). The rate at which beetles bored through the wood (136, 178, and 168 mm³/d at 20, 25 and 30°C, respectively) significantly differed between temperatures but did not differ with beetle weight. Temperature had a significant effect on the time it took adults to initiate boring (7, 5, and 4 d at 20, 25, and 30°C, respectively) and subsequently to complete boring to emerge (5, 4, and 4 d at 20, 25, and 30°C, respectively). This suggests that beetles require more than a week to progress from eclosion to emergence in wood, even at summer temperatures. This information on A. glabiipennis basic biology is critical for developing phenology models that are used to time exclusion and eradication methodologies. [ABSTRACT FROM AUTHOR]

In recent years, several attractant pheromones have been identified for cerambycid beetles, including 2-(undecyloxy)-ethanol (hereafter monochamol) for Monochamus galloprovincialis (Olivier), M. alternatus Hope, and M. scuteUatus (Say). This study screened eight known cerambycid pheromones or their analogues (including monochamol) as potential attractants for M. carolinensis Olivier and M. titillator (F.), in the presence and absence of the host volatile α-pinene. Monochamol attracted M. carolinensis in the presence and absence of α-pinene, whereas M. titillator was only attracted to the combination of monochamol and α-pinene. (2R*,3R*)-2,3-Hexanediol also attracted both M. carolinensis and M. titillator, but only in the presence of α-pinene. Subsequent coupled gas chromatography-mass spectrometry and gas chromatography-electroantennogram detection analyses of extracts of volatiles collected from both sexes demonstrated that male M. carolinensis and M. titillator release monochamol, and that antennae of males and females of both species detect it. These results indicate that monochamol is a male-produced pheromone for both M. carolinensis and M. titillator. [ABSTRACT FROM AUTHOR]

In September of 2004, Sirex noctilio F. (Hymenoptera: Siricidae) was detected in New York State and later found to be established over a larger area, including parts of southeastern Canada and the northeastern United States. A key component of S. noctilio detection and management plans in other parts of the world where S. noctilio has become established are chemically girdled trap trees. Trap tree usage in North America is confounded by the presence of diverse communities of organisms that inhabit dead and dying trees. We trapped a portion of the arboreal insect community arriving at Pinus resinosa Air. and Pinus sylvestris L., trap trees girdled 3 mo before (April), one month before (June), and at S. noctilio flight (July) in central New York. Multiple-funnel traps attached to trap trees captured 30,031 individuals from 109 species of Scolytinae, Cerambycidae, and Siricidae. Ips pini (Say) and Ips grandicollis (Eichhoff) accounted for almost 50% of the scolytines captured at trap trees and were present on all girdling dates. Significantly more scolytines and cerambycids were captured on P. sylvestris compared with P. resinosa, but species richness of captured insects did not differ between the two trees. More total and conifer-inhabiting scolytines and cerambyeids were captured in traps on trees girdled in April and June and higher observed species richness was found on trees girdled in April and controls. Results from this study suggest a large community of arboreal insects and associated organisms are attracted to chemically girdled trap trees and likely interact with S. noctilio. [ABSTRACT FROM AUTHOR]

We used life table analyses to investigate age specific mortality and to better understand the population dynamics of the red oak borer, Enaphalodes rufulus (Haldeman) (Coleoptera: Cerambycidae). We continually sampled populations within 177 trees at primarily two sites in the Ozark National Forest in Arkansas throughout three (2-yr) generations. The first cohort (adults emerged in 2003) was sampled during a severe population outbreak, whereas the second and third (2005 and 2007) were sampled during the population crash that followed. Generation mortality was 94% in 2003 and 99% in both 2005 and 2007. Estimates of apparent mortality indicated that the E. rufulus population crash likely occurred during or before the first overwintering period (2003-2004) of the generation that emerged as adults in 2005. We found limited evidence for density dependent mortality, which suggest that intraspecific competition after the first active feeding period was apparently not an important mortality factor during E. rufulus development. Life tables revealed that E. rufulus larvae generally experienced the greatest apparent mortality during the second summer of active feeding (80-94%) when larvae were feeding in, and moving between phloem and sapwood. The least apparent mortality was incurred during the following spring and early summer (26-67%) when late stage larvae and pupae were deepest and most protected within sapwood or heartwood tunnels. We found very little evidence for mortality from associated species. Scarring of vascular tissue in response to E. rufulus feeding occurred during early life stages and may be an important tree resistance mechanism and E. rufulus mortality factor. [ABSTRACT FROM AUTHOR]

Xylophagous insects derive nutrients from intractable substrates by producing or ingesting cellulolytic enzymes, or by maintaining associations with symbiotic microbes. Wood-boring cerambycid beetle larvae sometimes house maternally-transmitted endosymbiotic yeasts that are presumed to provide their hosts with nutritional benefits. These are thought to be absent from species in the large subfamily Lamiinae; nevertheless yeasts have been repeatedly isolated from the guts of neotropical lamiines. The objective of this study was to conduct transmission electron microscopy (TEM) studies of cerambycid larval midgut tissues to determine if gut yeasts were intracellular, or simply present in the gut lumen. Nine cerambycid larvae were harvested from two trees in the Brazil nut family (Lecythidaceae) in the rain forest of SE Peru; seven were identified using mtDNA sequence data and processed for TEM. Yeasts cultured from larval frass or exuvia, and identified with rDNA sequence data, were identical or similar to yeasts previously isolated from beetles. In TEM analyses yeast cells were found only in the gut lumens, sometimes associated with fragments of thick-walled xylem cells. Apparent bacteriocytes were found in either midgut or fat body tissue of three larval specimens, including two lamiines. This is the first report of a potential fat body symbiosis in a cerambycid beetle. Future studies of cerambycid symbiosis should distinguish the identities and potential roles of free-living organisms in the gut lumen from those of organisms harbored within gut epithelial or fat body tissue. [ABSTRACT FROM AUTHOR]

In longhorn beetles and many other internally feeding insects, oviposition choice by females is critical to the survival of their offspring because their larvae are incapable of moving between hosts. Here we report on the complex host selection and colonization strategies of a longhorn beetle, Glenea cantor (F.) (Coleoptera: Cerambycidae), which is an important pest of kapok trees [Bombax ceiba L. = Gossampinus malabaricus (DC.) Merr.] in southern Asia. It attacks weakened trees, eventually killing them. The typical oviposition behavioral sequence in the laboratory includes the following: oviposition site search and recognition using antennae and palpi, oviposition slit preparation with mandibles, turning body direction 180°, egg deposition with the ovipositor, and oviposition wound covering with a jelly-like material from the ovipositor. Bark moisture content significantly increases from the upper to lower sections in kapok trees. In accordance with this variation female adults select the upper section of trees first for oviposition. As infestation continues and the host becomes more weakened, ovipositing females move further down the tree for oviposition. Consequently, the larvae kill the hosts from the top down. We show that the jelly-like material or eggs or both have an olfactory role in attracting females to oviposit nearby. Our findings are important in terms of increasing our understanding of host selection and colonization mechanisms of internally feeding insects, particularly cerambycids, and the development of environmentally friendly pest management measures. [ABSTRACT FROM AUTHOR]

Tetropium fuscum (F.) attacks weakened Norway spruce, Picea abies (L.) Karst., in its native Europe and may colonize healthy spruce in Nova Scotia, Canada. We used manipulative field experiments to evaluate: 1) the development of T. fuscum on apparently healthy red spruce (Picea rubens Sarg.) in Nova Scotia; 2) the influence of red spruce physiological condition (healthy, girdled or cut) on T. fuscum performance; and 3) the impact of natural enemies and competitors on T. fuscum performance when developing on trees of varying condition. Tetropium fuscum successfully developed on healthy red spruce. Survival was higher on healthy than on girdled or cut trees when larvae were exposed to natural enemies and competitors. The benefits of reduced competition and parasitism on healthy trees appeared to compensate for any reductions in nutritional quality, increase in host resistance, or both. In contrast, when T. fuscum were protected from natural enemies, apparent survival was highest on girdled trees. Tetropium fuscum development took longer on healthy than on cut or girdled trees, and emerged adults were largest on healthy trees. The disparities in adult sizes among the three treatments may mean that healthy trees are more nutritious. Alternatively, the differences may indicate that a greater amount of time was spent feeding in healthy than in girdled or cut trees. Tree condition appears to have a direct impact on the success of T. fuscum, influencing survival, development time, and adult size, and may mediate the impact of natural enemies and competitors, further affecting T. fuscum performance. [ABSTRACT FROM AUTHOR]

Xylotrechus arvicola Olivier (Coleoptera: Cerambycidae) has become a new expanding pest in grape (Vitis spp.) crops. To better improve control tactics, the consequences of 11 constant (12, 15, 18, 21, 24, 27, 30, 32, 34, 35 and 36°C) and nine variable temperatures (with equal mean temperatures at each of the nine constant rates ranging from 15 to 35°C) on survival and embryonic development were studied. The eggs were able to complete development at constant temperatures between 15 and 35°C, with mortality rates at the extremes of the range of two and 81.5%, respectively. Using variable temperatures a mortality rate of 38.9% at a mean temperature of 15°C and 99% at 35°C was observed. The range of time for embryonic development was 29.5 d at 15°C to 6 d at 32°C at constant temperatures, and from 29.6 d at 15°C to 7.2 d at 32°C at variable temperatures. The goodness-of-fit of different development models was evaluated for the relationship between the development rate and temperature. The models that gave the best fit were the Logan type m for constant temperatures and the Brière for variable temperatures. Optimum temperatures were estimated to be from 31.7 to 32.9°C. The models that best described embryo development under natural field conditions were the Logan type m model for constant temperatures (98.7% adjustment) and the Lactin model for variable temperatures (99.2% adjustment). Nonlinear models predicted faster development at constant temperatures and slower development at variable ones when compared with real field development, whereas the linear model always predicted faster development than what actually took place. [ABSTRACT FROM AUTHOR]

Male Tetropium fuscum (F.) and T. cinnamopterum Kirby mated with live and dead (freeze-killed) conspecific females upon antennal contact, but did not respond to dead females after cuticular waxes were removed by hexane rinsing. Significantly fewer males of each species attempted to copulate with live or dead heterospecific females than with conspecifics, indicating that mate recognition was mediated by species-specific contact sex pheromones in the female's cuticular hydrocarbons. GC/MS analysis of T. fuscum elytra identified n-alkanes and mono-methyl branched alkanes of which 11-methylheptacosane and 3- and 5-methyltricosanes were dominant in females. Full male responses, including copulatory behavior, were restored with application of enantiomerically pure synthetic (S)-11-methyl-heptacosane at 40 /μg /female (one female equivalent) but not with racemic or (R)-11-methyl-heptacosane. The cuticular hydrocarbons on T. cinnamopterum elytra included U-methyl-heptacosane as well as n-alkanes, methyl-branched alkanes, mono-alkenes, and (Z, Z)-6, 9-alkadienes. (Z)-9-pentacosene, (Z)-9-heptacosene, and 11-methyl-heptacosane were female dominant, but only (Z)-9-pentacosene elicited precopulatory behaviors in conspecific males at levels similar to those behaviors elicited by unrinsed females, but elicited copulation in fewer than half of males. At female equivalent dosages (10 μg), neither (Z)-9-heptacosene nor (S)-11-methylheptacosane elicited responses in males that were significantly different from those responses to a rinsed female but when applied together, the proportion of males responding was significantly increased. 11-methyl-heptacosene is thus a contact pheromone component common to both species, which may explain the heterospecific mating attempts by some males. [ABSTRACT FROM AUTHOR]

The brown spruce longhorn beetle, Tetropium fuscum (F.), is an invasive wood-boring species in eastern Canada. Gas chromatographic/ectroantennographic (GC/EAD) analyses of Norway and red spruce volatiles detected a number of consistent EAD-active responses to compounds that are known to be stress-induced in spruce. The effects of these EAD-active compounds on various aspects of adult behavior were tested. In two-choice olfactometer assays, a monoterpene spruce blend, (R)- (-) -linalool, (3Z,6E) -α-farnesene, (E) -β-farnesene and spruce essential oil were attractive to both sexes. However, when they were combined with the male-produced pheromone (fuscumol), they elicited a sex-specific response: females were significantly attracted to combinations of fuscumol plus either (3Z,6E)-α-farnesene, (E)-β-farnesene and spruce essential oil but males were not, Fuscumol alone was unattractive to either sex in the olfactometer. Males exposed to fuscumol, (3Z,6E)-α- farnesene, or a combination of both, but not (E)-β-farnesene, were more likely to engage in the pheromone calling posture relative to controls. Both the monoterpene spruce blend and spruce essential oil elicited significantly greater trap capture of both sexes of T. fuscum in the presence of fuscumol and ethanol than (3Z,6E) -α-farnesene or (R) - (-) -linalool, which did not elicit trap capture alone or in combination with fuscumol. The data support the hypothesis that stress-induced sesquiterpene components, such as (3Z,6E)-α-farnesene, are important for mediating close-range attraction and behavior in T fliscurn while the monoterpene components are important for long-range processes (trap capture). [ABSTRACT FROM AUTHOR]

The co-existence of two closely related Tetropium species in eastern Canada, invasive T. fuscum and native T. cinnamopterum (TF and TC, respectively), provides a model system to investigate seasonal and spatial demographic parameters of biological invasions at the interspecific level. In this study, we take advantage of the similar semiochemical communication of TF and TC to evaluate the abundance of adults of the two species concurrently using grids of traps baited with pheromone and host volatiles in stands of spruce. Adult TF emerged on average 2 wk before TC both in the field and under controlled laboratory conditions. This observation, combined with the early reproduction of emergent females, implies that the smaller (younger) larvae of native TC may be at increased risk of intra-guild predation by TF. The high spatial association between male and female TF in dense, aggregated populations suggests that the rate of mate encounter is depressed in sparse populations toward the edge of the invasive range. The higher level of spatial aggregation for TF than TC, particularly at high population density, suggests a higher propensity of adult TF to congregate at "landmarks." Considering the broader range of host conditions, earlier seasonal emergence, and presumably more effective mate encounter for TF than TC, the exotic TF may be a superior competitor with the potential to displace or reduce the abundance of TC. [ABSTRACT FROM AUTHOR]

The molecular phylogeny of the long-horned beetle tribe Lamiini Mulsant (Coleoptera: Cerambycidae) in Japan (12 genera, 25 species, 3 additional subspecies) was determined based on mitochondrial 16S rRNA and cytochrome oxydase subunit I. The monophyly of the tribe Lamiini was supported, whereas that of the genus Acalolepta Pascoe was unclear. Evolution of host plant use in Lamiini was estimated using the molecular phylogeny, For adult and larval host plant kind-and-condition, the most ancestral state was for weakened to dead broad-leaved trees, whereas derived states favored conifers, healthy broad-leaved trees, and herbs. For adult and larval host range, the most ancestral state was polyphagy, whereas oligophagy and monophagy were derived. Evolution of hosts' idiosyncrasy and that of the insects' host range were related in many lineages. Our results partly support the hypothesis that habitation in living trees requires dietary specialization in phytophagous insects. [ABSTRACT FROM AUTHOR]

Epidemic populations of Enaphalodes rufulus (Haldeman), red oak borer, a native longhorned wood boring beetle, were implicated as a major contributor to a recent widespread oak mortality event in the Ozark National Forest of Arkansas. We assessed potential factors affecting suitability of a primary host Quercus rubra L., northern red oak, which experienced dieback and mortality throughout two successive borer cohorts. We sampled trees with various E. rufulus infestation levels during 2001-2003 when populations were at outbreak levels and 2003-2005 when borer numbers were declining, We measured phloem thickness and calculated a vigor index; the ratio of the past 5-yr basal area increment to sapwood area. We also counted established first year larval feeding galleries and outer-bark adult emergence holes and measured surface area of feeding galleries on a subset of Q. rubra to assess the importance of host susceptibility versus suitability. Phloem thickness did not exhibit any patterns among hosts of varying infestation levels and was therefore not likely an important factor limiting larval success. Less vigorous Q. rubra appeared to be the most suitable hosts, although it is unclear whether reduced vigor was initially caused by stress of E. rufulus infestation or environmental factors. Host suitability seems to be more important than host susceptibility, as numbers of initiated galleries were not consistently different among host infestation classes and between both cohorts, whereas numbers of emerging adults did differ predictably among host infestation classes. [ABSTRACT FROM AUTHOR]

The male-produced pheromone of Anoplophora glnbripennis (Motschulsky) (Coleoptera: Cerambycidae), which is an equal blend of 4-(n-heptyloxy)butan-1-ol and 4-(n-heptyloxy)butanal, was used in laboratory bioassays and in the greenhouse to determine its potential for attracting A. glabripennis adults. In modified "walking wind tunnels," virgin females were most attracted to the alcohol component, and virgin males were repelled by the pheromone blend at the lowest and highest amounts offered. Y-tube olfactometer bioassays also showed that females were significantly more attracted to the pheromone and its components than males were. However, males were more attracted to plant volatiles than females. Of 12 plant volatiles tested, δ-3-carene and (E)-caryophyllene were highly attractive to males, whereas (Z)-3-hexenyl acetate was repellent to males. Combining the male pheromone blend with () -linalool alone or with (Z) -3-hexen-1-ol attracted significantly more males than did the pheromone alone. We tested four trap designs in our quarantine greenhouse with eight different lures. The Intercept Panel traps and the hand-made screen sleeve traps caught more beetles than the Plum Curculio traps and Lindgren funnel traps. Intercept traps worked best when baited with male blend and (Z)-3-hexen-1-ol, whereas screen sleeve traps were most attractive when baited with () -linalool. Our findings provide evidence of the attractiveness of the A. glabripennis male-produced pheromone and suggest that it has a role in mate-finding. It is also a first step toward the development of an efficient trap design and lure combination to monitor A. glabripennis infestations in the field. [ABSTRACT FROM AUTHOR]