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In 2022, two independent insect surveys in canton Ticino (southern Switzerland) revealed the widespread occurrence of the invasive ambrosia beetleAnisandrus maichefrom southern to central-upper Ticino. This species is native to east Asia and has previously been found as a non-native invasive species in the United States, Canada, western Russia, Ukraine and, in 2021, in northern Italy. Here, we present the results of several trapping studies using different trap types (bottle traps, funnel traps and Polytrap intercept traps) and attractants and a map of the distribution of the species. In total, 685 specimens ofA. maiche, all female, were trapped, and the identity of selected individuals was confirmed by morphological and molecular identification based on three mitochondrial and nuclear markers (COI, 28S and CAD). Traps checked from early April to early September 2022 in intervals of two to four weeks showed that flights ofA. maicheoccurred mainly from June to mid-August. Isolation of fungal associates ofA. maichefrom beetles trapped alive revealed the presence of four fungal species, including the ambrosia fungusAmbrosiella cleistominuta, the known mutualists ofA. maiche. The identity ofA. cleistominutawas confirmed by comparing DNA sequences of its nuclear, internal transcribed spacer (ITS) gene with reference sequences in NCBI and BOLDSYSTEMS. This represents the first record ofA. cleistominutain Europe.Ambrosiella cleistominutawas also found in association with another non-native invasive ambrosia beetle,Xylosandrus crassiusculus, at a botanic garden in central Ticino. As ambrosia beetles usually show a high degree of fidelity with only one mutualistic fungus (in the case ofX. crassiusculusnormallyAmbrosiella roeperi), this association is highly unusual and probably the result of lateral transfer among these non-native invasive species. Of the other fungal associates isolated fromA. maichein Ticino,Fusarium lateritiumis of note as there is a possibility thatA. maichecould act as a vector of this plant pathogen. We highlight several research needs that should be addressed to gain insight into the potential impact of these non-native species and to overcome problems with heteroplasmy in COI sequences in studies of invasion and population genetics of ambrosia beetles.

Pinus sylvestris is an important production tree. In recent years, there has been a sharp increase in the mortality of pine trees due to insect pests. It is obvious that some pests profit from climatic changes, increase their aggressiveness and spread to new localities. The study aimed to investigate the spectrum of more abundant insect pest species in pine plantations of Czechia. The occurrence of species and intensity of their infestation were studied at 77 localities situated in six regions. Any abundant foliophagous insect species were noticed. Bark beetles and wood-boring insects were found to be prevalent. Namely, Ips acuminatus, Ips sexdentatus, Phaenops cyanea and Sirex noctilio seem to be the most dangerous. These species are now better competitors than species previously considered as main pests. Their aggressiveness, expansion to new areas and interspecies co-occurrence are alarming. Due to the advancing climate change, pine mortality due to bark beetles and wood-boring pests will probably continue to increase.

We present the first record of the tropical ambrosia beetle Xyleborus bispinatus in the Iberian Peninsula, collected in traps located in Murcia, Alicante and Valencia provinces (Spain). Insects have been captured in baited traps of long-time trapping networks (ESFP, MUFFET, RAT and SAMFIX) installed in Eastern Spain. Several individuals (410) of X. bispinatus have been collected in seven locations, first in 2009 in Murcia Region, and from 2018 to 2021 in Valencia Region. No attacks by X. bispinatus have been detected on plants thus far, and therefore the host plant in Spain remains unknown. Stable X. bispinatus populations have been detected in a wide area of central Valencian province. We may consider this as an alarming scenario that should be kept under surveillance by maintaining the current trapping network and intensifying the search for the host plants. A portion of MK’s research was supported by the Ministry of Agriculture of the Czech Republic, institutional support MZE-RO0118. Research in related with SAMFIX trap network was supported by Life SAMFIX LIFE17 NAT/IT/000609. NDS was funded by Lazio Region (Agricultural Department) and Università degli Studi della Tuscia.

The northern bark beetle (Ips duplicatus), in Europe originally restricted to northern countries, expanded its distribution range to eastern Europe in the 20th century and is now causing considerable damage in spruce forests. In the past decades its presence has been confirmed in several Central European countries. By means of pheromone traps and visual inspection of infested logs, in this study we demonstrate that I. duplicatus is also present in the Rhine valley in Switzerland and Liechtenstein. Breeding galleries with beetles and exit holes in an infested spruce log indicate that the trapped beetles had successfully developed in a local stand nearby. An inquiry addressed to European entomologists was carried out to obtain information and references concerning the year of the first record or mention of I. duplicatus in their respective countries. This information substantiated the expansion of its historical range to the southeast in the middle of the last century and clearly showed recent movement westward, with Switzerland and Germany currently the westernmost countries where this species occurs. This recent range expansion is likely attributed to the transport of infested timber. The economic significance of this expanding bark beetle species is discussed in view of its co-occurrence with the notorious pest species I. typographus.

In the tropics, antagonistic seed predation networks may have different properties than mutualistic pollination and seed dispersal networks, but the former have been considerably less studied. We tested whether the structure of antagonistic tripartite networks composed of host plants, insects developing within seeds and fruits, and their insect parasitoids could be predicted from plant phylogenetic distance and plant traits. We considered subsets of the networks (“subnetworks”) at three rainforest locations (Panama, Thailand, Papua New Guinea), based on insect families, plant families or plant functional groups. We recorded 3,197 interactions and observed a low percentage of realized interactions, especially in Panama, where insect host specificity was higher than in Thailand or New Guinea. Several factors may explain this, including insect faunal composition, incidence of dry fruits, high fruit production and high occurrence of Fabaceae at the Panamanian site. Host specificity was greater among seed-eaters than pulp-eaters and for insects feeding on dry fruits as opposed to insects feeding on fleshy fruits. Plant species richness within plant families did not influence insect host specificity, but site characteristics may be important in this regard. Most subnetworks were extremely specialized, such as those including Tortricidae and Bruchinae in Panama. Plant phylogenetic distance, plant basal area and plant traits (fruit length, number of seeds per fruit) had important effects on several network statistics in regressions weighted by sampling effort. A path analysis revealed a weak direct influence of plant phylogenetic distance on parasitoid richness, indicating limited support for the “nasty host hypothesis”. Our study emphasizes the duality between seed dispersal and seed predation networks in the tropics, as key plant species differ and host specificity tends to be low in the former and higher in the latter. This underlines the need to study both types of networks for sound practices of forest regeneration and conservation.

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 species of Scolytinae (Coleoptera: Curculionidae) are described from Jammu and Kashmir, Pseudothysanoes kashmirica sp. nov. and Sphaerotrypes montanus sp. nov. These discoveries mark the first records of the genera Pseudothysanoes Blackman,1920 from South Asia and Sphaerotrypes Blandford, 1894 from the Northwestern Himalayan region. A discussion on the biology of the new species together with a complete key to the known species of Sphaerotrypes from South Asia are provided.

Insect seed predators are important agents of mortality for tropical trees, but little is known about the impact of these herbivores in rainforests. During 3 years at Khao Chong (KHC) in southern Thailand we reared 17,555 insects from 343.2 kg or 39,252 seeds/fruits representing 357 liana and tree species. A commented list of the 243 insect species identified is provided, with details about their host plants. We observed the following. (i) Approximately 43% of identified species can be considered pests. Most were seed eaters, particularly on dry fruits. (ii) Approximately 19% of parasitoid species (all Opiinae) for which we could determine whether their primary insect host was a pest or not (all Bactrocera spp. breeding in fruits) can be considered beneficials. (iii) The seeds/fruits of approximately 28% of the plant species in this forest were free of attack. Phyllanthaceae, Rubiaceae and Meliaceae were attacked relatively infrequently; in contrast, Annonaceae, Fabaceae, Sapindaceae and Myristicaceae were more heavily attacked. There was no apparent effect of plant phylogeny on rates of attack but heavily attacked tree species had larger basal area in the KHC plot than rarely attacked tree species. (iv) Insects reared from fleshy fruits were more likely to show relatively stable populations compared to insects reared from dry fruits, but this was not true of insects reared from dipterocarps, which appeared to have relatively stable populations throughout the study period. We tentatively conclude that insects feeding on seeds and fruits have little effect on observed levels of host abundance in this forest.

Trypodendron laeve Eggers, 1939 is a species of ambrosia beetle much less known than the other three Trypodendron species occurring in Europe. Its status (native or alien) in Central Europe has been a subject of debate over the past two decades. In Romania, the species was discovered in 2008 and the aim of the research presented in this paper was to investigate its distribution in the Carpathians, mainly at high altitudes (>800 m), in tree stands with Norway spruce (Picea abies [L.] H. Karst). Panel intercept traps baited with synthetic pheromone for Trypodendron lineatum (Olivier, 1795) were used in the spring of 2015, at 31 locations. Adults of T. laeve were caught in 20 of them. Additional observations were made within some studies using similar baits and T. laeve specimens were caught in eight locations. T. laeve was always trapped together with T. lineatum, and at some locations also together with T. domesticum (Linnaeus, 1758) and T. signatum (Fabricius, 1787). In all traps, fewer specimens of T. laeve were caught compared to T. lineatum. The species has a widespread distribution in the mountain regions, within forests composed of native tree species and generally located far away from commercial routes. There, it occurs together with other native species of the same taxonomic genus. It seems to be more abundant at high altitudes, but overall its populations are less abundant than those of T. lineatum.

The Asian ambrosia beetle, Cyclorhipidion fukiense (Eggers) was detected for the first time in North America based on three specimens trapped in 2012 from three localities in South Carolina and two other specimens intercepted at the port of Savannah, Georgia, in 2010. The species is characterized, illustrated with high-resolution images, and compared with two other congeneric, adventive species (C. bodoanum and C. pelliculosum) presently established in eastern North America. Morphometric measurements are provided and a provisional key is presented to the species of Cyclorhipidion occurring in North America.

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

Johnson, Andrew J., Knížek, Miloš, Atkinson, Thomas H., Jordal, Bjarte H., Ploetz, Randy C., Hulcr, Jiri (2017): Resolution of a Global Mango and Fig Pest Identity Crisis. Insect Systematics and Diversity 1 (2): 1-10, DOI: 10.1093/isd/ixx010, URL: http://dx.doi.org/10.1093/isd/ixx010

Bark and ambrosia beetles from the subfamily Scolytinae are among the most important pests in forests of Northern Iran. During investigations conducted in 2013–2016 in different parts of northern forests, the species Crypturgus cribrellus Reitter, Liparthrum bartschti Mühl, Scolytus varshalovitchi Michalski, Scolytus sulcifrons Rey, Scolytus triarmatus (Eggers) and Trypophloeus granulatus (Ratzeburg) were recorded for the first time in Iran; Trypophloeus and Liparthrum were new genera for Iran. As new host plants we found Zelkova sp. for Scolytus varshalovitchi, Michalski, Populus sp. for Liparthrum bartschti, Mühl, Alnus sp. and Pterocarya fraxinifolia for Taphrorychus lenkoranus Reitter, Pterocarya fraxinifolia for Ernoporicus caucasicus (Lindemann), Carpinus sp. for Pteleobius vittatus (Fabricius), Parrotia persica for Scolytus intricatus (Ratzeburg), Alnus sp. and Pterocarya fraxinifolia for Hypothenemus eruditus (Westwood).

In the search for compounds that contribute to the host or habitat discrimination, antennae of Ips typographus were screened for sensitivity to volatiles released by spruce trap-trees using gas chromatography linked to electroantennography. The antennally active compounds were determined using comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometric detection. Data show that I. typographus antennae respond to compounds emitted by the host. In total, 18 of antennally active compounds were detected: α-pinene, camphene, sabinene, β-pinene, myrcene, Δ-3-carene, p-cymene, limonene, β-phellandrene, 1,8-cineole, γ-terpinene, terpinolene, nonanal, camphor, trans-pinocamphone, cis-pinocamphone, terpinen-4-ol, and verbenone. Unequivocal identification of all active minor compounds is provided and confirmed using synthetic standards. Compounds in minor quantities like 1,8-cineole, β-phellandrene, camphor, cis-pinocamphone, and trans-pinocamphone were more active than major spruce monoterpenes. We hypothesize that the minor spruce compounds may play so far unrecognized role in conveying information about host suitability for I. typographus.

In reviewing the occurrence of the bark beetle Dendroctonus micans in the Czech Republic over the past 100 years, we found that D. micans has been detected at 80 localities with elevations ranging from 158 to 1350 m a.s.l. During 2011–2012, we recorded three local outbreaks on Picea pungens , two of which involved isolated trees in urban areas between houses (always on sites D. micans were obtained and dissected. Among these dissected specimens, nematodes in the hemolymph were detected in only 5 adults and 11 larvae. No other parasites or pathogens were found in the D. micans specimens. Low numbers of the beetle Rhizophagus grandis , which is a specific predator of D. micans , were detected, and none contained parasites or pathogens. Locally D. micans could constitute a new limited threat to urban trees, including P. pungens , in the Czech Republic and Central Europe . Special attention should be given to solitary P. pungens trees; if D. micans is detected on these trees, defensive measures must be taken to protect uninfested trees in the vicinity.

Xyleborinus octiesdentatus (Murayama), an ambrosia beetle native to Asia, is reported for the first time in North America based on specimens from Alabama and Louisiana. This is the twenty-first species of exotic Xyleborina documented in North America. A re-description of the female and a key to the four North American species of Xyleborinus are presented.

A new species of Bothinodroctonus in the tribe Polygraphini is described from Gambia and Kenya. This is the first representative of the genus in Afrotropical region. A holotype based description contains also the intraspecific variety of the newly described species based on available specimens and differential diagnoses to species within the genus.

The spruce bark beetle, Ips typographus (L.) is the most serious pest of mature spruce stands, mainly Norway spruce, Picea abies (L.) Karst. throughout Eurasia. A complex of weather-related events and other environmental stresses are reported to predispose spruce stands to bark beetle attack and subsequent tree mortality; however the possible role of industrial pollution as a predisposing factor to attack by this species is poorly understood. The abundance and dynamics of I. typographus populations was evaluated in 60-80 year old Norway spruce stands occurring on 10 x 50 ha sites in five countries within the Carpathian range that were selected in proximity to established ozone measurement sites. Data were recorded on several parameters including the volume of infested trees, captures of adult beetles in pheromone traps, number of attacks, and the presence and relative abundance of associated bark beetle species. In several cases, stands adjacent to sites with higher ozone values were associated with higher bark beetle populations. The volume of sanitary cuttings, a reflection of tree mortality, and the mean daily capture of beetles in pheromone traps were significantly higher at sites where the O(3) level was higher. However, the mean infestation density on trees was higher in plots associated with lower O(3) levels. Captures of beetles in pheromone traps and infestation densities were higher in the zone above 800 m. However, none of the relationships was conclusive, suggesting that spruce bark beetle dynamics are driven by a complex interaction of biotic and abiotic factors and not by a single parameter such as air pollution.

A review of the New Zealand Scolytinae and Platypodinae has been carried out, revealing a relatively small fauna of at least 19 indigenous Scolytinae, of which 9 species are currently undescribed, and four Platypodinae. Despite the frequent interception of exotic species in imported timber and wooden items, there are only 11 introduced Scolytinae, primarily of Australian and European origin.We provide numerous corrections of incorrect synonyms and records of occurrence in New Zealand, and a new combination, Hypocryphalus longipennis (Browne), transferred from Cryphalus, is proposed. For each species we provide its known distribution and host plants in New Zealand. None of the indigenous species are economically important in New Zealand. Of the introduced species, only Hylurgus ligniperda (Fabricius) and Hylastes ater (Paykull), which breed primarily in woody debris available in pine plantations, are abundant, but their economic impact is limited. As a vector of Dutch elm disease, Scolytus multistriatus (M...

Semiochemicals (compounds used for chemical communication within and between species) are usually produced in tiny amounts that vary from picograms to nanograms. As a consequence, pheromones are rarely isolated in quantities sufficient to carry out the full range of spectroscopic tests (1H and 13C NMR, infrared, and mass spectrometry) routinely used in structural organic analysis. Pheromone identifications predominantly rely on gas chromatography coupled with mass spectrometry (GC-MS) and electroantennographic detection (GC-EAD) (Struble & Arn, 1984). The GC-EAD analysis, where insect antenna is used as specific biological detector, helps to focus the identification effort only on a particular part of the chromatogram. Quite often, however, the GC-EAD indicates an activity in chromatogram areas where FID or MS detects no compound (Svatos et al., 1999, 2006; Kalinova et al., 2006) or the active compound is overlapped by higher amount of nonactive one(s).