A comprehensive list of the currently (as of 17 November 2025) valid taxa of bark and ambrosia beetles of the world (Curculionidae: Scolytinae) is presented, including all tribes, genera, species (6516), and subspecies. The high diversity of scolytine species, their biosecurity significance, and the rapidly advancing understanding of their phylogenetic relationships has resulted in decentralized and often incorrect usage of names. The list represents species names accepted and used in compliance with the International Code of Zoological Nomenclature and a consensus of name usage by the community of active systematists. Species names listed here are bona fide hypotheses of biological species, but not always of confirmed biological entities; instead, the list aims to provide a foundation for the subsequent taxonomic, biological, and phylogenetic work on species resolution, and for biodiversity data management. The list is presented as a formatted checklist, as well as a Darwin-core format enabling interpolation into biodiversity information systems. Two replacement names were needed to resolve homonyms, Hylastes woodi Johnson, nom. nov. (= Hylastes niger Wood, 1974) and Taphrorychus krivolutskayae Johnson, nom. nov. (= Dryocoetes aceris Krivolutskaya, 1968).

Bark beetles and pinhole borers of Georgia and Kyrgyzstan were surveyed between 2003 to 2025. Specimens were collected using pheromone traps baited with Acuwit, IAC Ecolure, Sexowit, Tomowit, and ethanol; 0.5-m-long logs exposed for bark beetle colonisation; direct hand collecting in the field; searches for potential feeding substrates; and rearing from infested host material. We present 51 faunistic records of bark beetles and pinhole borers, comprising 44 species from Georgia and seven from Kyrgyzstan. One taxon is newly recorded from Georgia: Pityophthoruspityographus cribratus. Finally, we provide complete checklists of bark beetles and pinhole borers recorded from Georgia (98 species) and Kyrgyzstan (34 species).

Ambrosia beetles (Coleoptera, Curculionidae) form obligate nutritional symbioses with ambrosia fungi cultivated within their galleries. Among them, the pinhole borers (Platypodinae) are predominantly tropical, with only two representatives native to Europe. One of them, the rare and understudied Treptoplatypus oxyurus, primarily colonises Abies alba. We investigated its fungal symbionts using a cultivation-dependent approach. We identified three numerically dominant associates in the prothorax containing mycangia: Candida schatavii, Magnusiomyces fungicola, and a novel member of Ophiostomatales. The latter, Wilhelmdebeerea oxyuri gen. et sp. nov., was the most abundant and exhibited both leptographium-like and hyalorhinocladiella-like morphs. Additionally, two new yeast species of low abundance and uncertain ecological roles were isolated and described: Blastobotrys sasensis sp. nov. and Sugiyamaella casensis sp. nov., both belonging to the family Trichomonascaceae (Dipodascales). Multigene and phylogenomics analyses confirmed the distinct taxonomic placement of all three new species. The ecological roles of the identified fungi and the strength of their association with T. oxyurus require confirmation through further studies at additional locations. Our findings reveal a previously undocumented fungal diversity tightly linked to a unique pinhole borer, T. oxyurus, thereby enriching our understanding of the fungi associated with conifer-colonising beetles and their ecological and biotechnological importance.

Accurate and timely prediction of bark beetle-related timber volumes is essential for minimizing economic losses and for ensuring effective logistics management in both the forestry and wood-processing sectors. Therefore, this study focuses on analysing the predictive capacity of interim reports on salvage logging volumes to estimate the final annual impacts of bark beetle outbreaks. Based on a regression analysis of time-series data from the Czech Republic (2007-2024), we examined the relationship between mid-year and three-quarter reports and the total annual volume of bark beetle-affected timber. The results demonstrate a very strong correlation for both reporting periods. However, the analysis revealed that the relationship between mid-year and annual volumes does not correspond to a simple linear doubling; instead, it requires the application of a multiplication factor of approximately 3.1. This pattern reflects the phenology of the spruce bark beetle (Ips typographus) and delays in detecting infestations during the first half of the year. In contrast, three-quarter reports show high stability and align with the theoretical expectation of volume completion at the end of the year. The study confirms that interim reporting can serve as a robust tool for early prediction and strategic planning in forest management.

Triotemnus ibericus sp. nov. from Iberian Peninsula is described. This is the first species of Triotemnus from the Spainish mainland. External morphology of the new species and all morphologically similar Triotemnus species are discussed. The new species is morphologically related to species from Morocco and Algeria, possesses several distinctive morphological characters on the elytral declivity. Geographical distribution and the probability of endemicity are discussed.

Cryphalus morivorus (Coleoptera: Curculionidae: Scolytinae), a bark beetle species previously known only from East Asia, is reported here for the first time in Europe. The species was found in association with Morus alba and M. alba 'Pendula' at four municipality-level localities in the Danubian Lowland and the Lu & ccaron;enec Basin, western and southern Slovakia. Infested twigs and small branches showed wilting and dieback associated with subcortical galleries, although no cases of whole-tree mortality were observed. Identification was based on morphological traits and supported by molecular analyses of the 28S rDNA and COI genes. In addition to recently collected field material from May 2025, previously collected herbarium specimens were examined, allowing the earliest occurrence of the species in Slovakia to be dated to 2022. The pathway of introduction of C. morivorus into Europe remains uncertain but was most likely linked to the international trade of ornamental Morus plants. The presence of characteristic galleries and adult beetles across multiple sites and years indicates that the species is established and reproducing locally. This discovery highlights the increasing risk of exotic bark beetle introductions associated with ornamental and landscape tree plantings. It underscores the importance of early detection and monitoring of mulberry trees to mitigate potential long-term ecological, socio-cultural, and management-related impacts.

The ambrosia beetle Xylosandrus compactus (Eichhoff, 1876), originally from Southeast Asia, was first found in Europe in 2010, specifically in Italy. Since then, X. compactus has rapidly spread across southern Europe, including France, Spain, Greece, Turkey, Malta, Slovenia, Russia, Croatia, and Switzerland, gradually moving northward through lower-elevation areas. In 2023, a single female was found near the village of Kameno in Montenegro. This female was sifted through leaf litter in rocky terrain within a deciduous forest mainly populated by oak and hornbeam trees, located 2.5 km from the international port of Herceg Novi.

Little is known about the influence of mating strategies that could potentially facilitate the colonization of new hosts in outbreeding species of the weevil subfamily Scolytinae. Individuals typically emerge from their host tree, disperse, and then mate with unrelated conspecifics in a new host where the females establish maternal galleries. Yet, in several spe-cies commonly classified as outbreeding, females have been found already mated before host colonization. Precolonization mating provides female with a sperm supply before they find a new host and allows them to establish a maternal gallery on their own. We compared the proportion of females mated before host colonization across 18 European and four American outbreeding Scolytinae species using a phylogenetically controlled analysis. To this end, we determined whether females caught in the spring had sperm in their spermathecae. We found that a proportion of females (range: 16-100%) mated before host colonization in all 22 species. Moreover, this trait was biased, although not significantly, toward invasiveness. Species known to have established outside their native range (Scolytinae with an Invasion History-SIH) displayed a higher proportion of females mated before host colonization than did species restricted to their native range (non-SIH). In Hylurgus ligniperda (Fabricius), a Palearctic species currently present across the globe, the proportions of females mated before host colonization reach 90% in the species' native range and up to 99% in its nonnative range (Argentina and New Zealand). Overall, these results show that precolonization mating is widespread among the Scolytinae. This trait could enhance the invasive capacities of outbreeding species by allowing females to establish a maternal gallery independently of any male during colonization, thus facilitating the establishment and spread of species introduced in new geographical areas.

Hylurgus ligniperda (F.) is a highly successful invader among bark beetles (Scolytinae) and forest insects in general. Native to the western Palearctic region, it has become established in every continent where its host plants ( Pinus spp.) occur. Especially in southern hemisphere regions with large pine plantations, it is often highly abundant. As a repeat invader with a wealth of information on various aspects relevant for biological invasions, it is highly suitable as a model organism for studying the role of international trade, the planting of non-native trees, and the potential occurrence of bridgehead invasions (where abundant non-native populations precipitate further invasions). In the present study, our specific objectives were to reconstruct the worldwide invasions of H. ligniperda and the pathways involved by using a multi-pronged approach including population genetics, analysis of historic interception data generated from inspections of imports, and records of establishments in the literature. Our review of the native and non-native ranges of H. ligniperda and the chronology of establishments revealed at least 13 separate invasions of non-native regions, beginning with Madeira (Portugal) before 1850, and, most recently, eastern China in 2019. We compared the population genetics of 464 specimens from eight countries in the native range and eight countries in the non-native range. Sequencing of the mitochondrial COI gene revealed the presence of 29 haplotypes in six well-supported clades, based on a Bayesian analysis. Non-native populations had significantly lower haplotype diversity (mean h = 0.219) than populations in the native range (mean h = 0.691). Countries in the non-native range had an average of about two haplotypes compared with about four haplotypes in native countries. In the non-native range, only one or two haplotypes were dominant, and these differed among invaded regions except for haplotype HL-H3 which occurred in Australia, New Zealand and China as well as in four countries in southern Europe, and HL-H4 which was dominant in New Zealand, California, New York State, and eastern China as well as two countries in southern Europe. Analyses of interceptions of H. ligniperda with imports arriving in five countries revealed that between 74% and 99% of interceptions originated from other non-native regions while in the USA, most interceptions were linked to imports from the native range beginning in the 1970s. Based on the combined evidence of the chronology of invasions, interception data, and analysis of haplotype distribution, we conclude that the early invasions (before 1950) probably all originated from the native range, while several of the more recent invasions probably originated from parts of the non-native range (suggestive of a bridgehead effect). However, it cannot be determined with certainty what the original sources of each of the invading populations were. ### Competing Interest Statement The authors have declared no competing interest. National Science Foundation, DBI-1639145 Ministry of Agriculture of the Czech Republic, MZE-RO0123 Russian Science Foundation, https://ror.org/03y2gwe85, 22-16-00075

Most phytophagous insects are specialists, so availability of suitable host plants often may be a critical factor limiting establishment of non-native insect species. Here we investigate the extent to which established non-native tree-feeding insects utilize hosts that are native to the invaded range as well as hosts that are themselves non-native. We accomplish this by comparing host use among all native and non-native bark beetles and pinhole borers (Scolytinae and Platypodinae) established in Europe and North America reported in the literature. These groups of insects are well-known for the disparity among species in specialized behavior and development tied to host physiology. We find considerable variation in host breadth, as measured by species-level and genus-level host richness and phylogenetic diversity of hosts, among different feeding guilds (ambrosia beetles, true bark beetles, twig beetles, and others). In each region, ambrosia and twig beetles exhibit the greatest diversity of hosts. Host breadth on native plants was generally greater for native beetle species than for non-native beetle species. In contrast, host breadth of non-native beetles is generally greater on non-native plants than on plants native to the focal region. These results indicate that successful invasion of these insect herbivores is dependent on the prior introduction of their non-native host plants, or the availability of native hosts that are closely related to their ancestral host plants.

A new species of Phloeosinus Chapuis, 1869 from Bhutan is described. The species is suggested to be endemic to Bhutan, occurring on Cupressus corneyana Knight & Perry ex Carrière (Cupressaceae).

Bark beetles (Curculionidae: Scolytinae) represent an important insect group including many significant pest species, but in some cases, the distribution and ecology of many bark beetles are still not well known. Maple bark beetle Scolytus koenigi Schyverew, 1890 is one of the mentioned group of species. The following study presents i) the first data of the occurrence of S. koenigi in Bohemia, ii) the first data of the species occurrence in an urban environment (large cities - Prague and Brno), iii) the distribution of the species in the Czech Republic since its first record (in 2013), and iv) new data about the bionomy of the species (i.e. a new host tree - Acer pseudoplatanus L. and refinement of the colonized substrate range diameter).

Ambrosia beetles are highly successful as invaders because they are often transported internationally with wood packaging and other wood products and because their inbreeding mating systems facilitates establishment of invading populations. In 2022, two independent insect surveys in canton Ticino (southern Switzerland) revealed the widespread occurrence of the invasive ambrosia beetle Anisandrus maiche (Kurentzov, 1941) from 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, 715 specimens of A. 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). Trap samples from early April to early September 2022 in intervals of two to four weeks showed that flights of A. maiche occurred mainly from June to mid-August. Isolation of fungal associates of A. maiche from beetles trapped alive revealed the presence of four fungal species, including the ambrosia fungus Ambrosiella cleistominuta, the known mutualist of A. maiche. The identity of A. cleistominuta was 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 of A. cleistominuta in Europe. Of the other fungal associates isolated from A. maiche in Ticino, Fusarium lateritium is of note as there is a possibility that A. maiche could 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.

AbstractIn 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.

In 2022, two independent insect surveys in canton Ticino (southern Switzerland) revealed the widespread occurrence of the invasive ambrosia beetle Anisandrus maiche from 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 of A. 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 of A. maiche occurred mainly from June to mid-August. Isolation of fungal associates of A. maiche from beetles trapped alive revealed the presence of four fungal species, including the ambrosia fungus Ambrosiella cleistominuta , the known mutualists of A. maiche . The identity of A. cleistominuta was 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 of A. cleistominuta in Europe. Ambrosiella cleistominuta was 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 of X. crassiusculus normally Ambrosiella 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 from A. maiche in Ticino, Fusarium lateritium is of note as there is a possibility that A. maiche could 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.### Competing Interest StatementThe authors have declared no competing interest.* FPS : Forest Protection Switzerland (Waldschutz Schweiz), Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland MSNL : Museo di storia naturale (Natural History Museum), Lugano, Switzerland PHP : Phytopathology, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland UPN : Ufficio della Natura e del Paesaggio, Bellinzona, Switzerland WSL : Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland

Dataset consists of two databases one for European and one for North American Curculionidae with the information about their taxonomy, feeding guilds, nativeness and host data needed for analyses. Other part of dataset has 6 different R scripts. Four of them are for calculating phylogenetic diversity of native/non-native European/North American beetles and two of them shows which type of variance analyses were used. The database of beetles for each continent provide all beetles analysed in manuscript. Each beetle has Subfamily, Tribe, Genus, Species, Feeding guild and Nativeness provided. Each row is one beetle - host connection. Host data are prepared on genera level. For each host you can find host family, subfamily if available, and host genus. The information about host status shows if the host were taken as primary and used in analyses or secondary and wasn't included in calculations.

Silver fir (Abies alba, Mill.) is threatened by many factors in Central Europe, among which bark beetles of the genus Pityokteines play an important role. To improve the silver fir conservation, it is essential to adopt appropriate management practices. For this reason, we studied the occurrence of Pityokteines bark beetles in four sites located in climatically different conditions. In each site, five WitaTrap 5-segment pheromone funnel traps were placed from early April to late September in both 2021 and 2022. Two species, P. spinidens and P. vorontzowi, were captured. P. vorontzowi was significantly more abundant at all sites. Individuals of both species were recorded in the traps mainly in the period of April-August. The most abundant occurrence of beetles was at the site Nizbor, which can be explained by regional climatic differences (lowest elevation, higher mean temperatures and lower mean precipitation). The differences between sites can be also explained by different methods of forest protection applied. The study confirmed the presence of Pityokteines bark beetles and their dependence on climatic characteristics and forest management.

Identifying alien species is important to ensure the early detection of biological invasions and survey shifts in species distributions in the context of global change. Here, we report on three alien bark and ambrosia beetles newly detected in Switzerland: Cyclorhipidion distinguendum (Eggers, 1930), C. pelliculosum (Eichhoff, 1878), and Hypothenemus eruditus (Westwood, 1834). These species were recorded for the first time during a comprehensive survey of saproxylic beetles accross major forest types and along an altitudinal gradient during the entire growing season in the southern Alps, in the canton of Ticino. Their local abundance and number of occurrences accross different lowland forest habitats, including alluvial forests of national importance, indicates that all three species are already naturalized. Given their polyphagy, it is likely that all three species will become more extensively distributed across Switzerland, with a yet unknown environmental impact.