Ambrosia beetles of the Euwallacea fornicatus species complex are emerging tree pests with a broad host range including important agricultural crops. Native to Southeast Asia, these species were introduced into various countries, where they cause considerable damage to many tree species. Here we report several outbreaks of E. fornicatus s.l. in Europe. The first individuals were found in 2017 in a palm house of a botanical garden in Poznan (Poland) whereas in 2020 an outbreak was detected in a tropical greenhouse in Merano (Italy). In 2021, two additional outbreaks were detected in two greenhouses in Germany, in Erfurt and Berlin. For both cases in Germany it was possible to trace back the invasion to a distributor of exotic plants in the Netherlands where several infested plants were detected. Molecular analyses show that individuals from Poland and Italy are genetically identical but belong to a different mitochondrial clade than individuals in Germany which are identical to most individuals of two greenhouses in the Netherlands. Moreover, in the two greenhouses in the Netherlands we found beetles that belong to another haplotype of E. fornicatus and two haplotypes of E. perbrevis, a species in the E. fornicatus complex, which has not been previously intercepted in Europe. Our study provides novel insights into the invasion history of E. fornicatus and the eradication measures in Europe. Considering the potential of introduction and establishment of Euwallacea ambrosia beetles, particular attention should be paid to monitor the presence of these pests in tropical greenhouses across Europe.

Background: Resources of dying and dead trees, decaying fragments of stems, stumps and branches, i.e., coarse woody debris (CWD), are an important structural element of biocenoses and are drivers of biodiversity. The aim of this study was to describe assemblages of saproxylic beetles in pine stands of western Poland in view of dead wood resources. We present faunistic (species identity) and quantitative (species and individual counts) data from two types of stands: 1. unmanaged pine stands, in which no trees have been extracted for over 30 years, with processes connected with tree dying and self-thinning of stands being undisturbed, 2. managed pine stands, in which routine tending operations extracting trees are performed in accordance with forest management plans and naturally dying trees are removed in the course of tending and sanitary logging; Methods: Beetles were captured in the years 2013–2014 using window flight traps. Assemblages of saproxylic beetles were assessed based on the indices of dominance, diversity (the Shannon–Weiner index), and species richness (Margalef’s index) as well as the estimated habitat fidelity index, feeding habits, and zoogeographical distribution. Similarity between the assemblages was evaluated applying cluster analysis. Dependence between dead wood resources and the diversity and species richness indices were analysed; Results: A total of 2006 individuals classified to 216 species were captured. Assemblages show considerable similarity on the local scale. Higher values of species diversity indicators were observed in unmanaged stands, in which no sanitation cuttings are performed; Conclusions: The decision to refrain from sanitation logging in pine monocultures results in increased CWD resources, which nevertheless does not lead to a marked increase in the values of biodiversity indicators. Unmanaged stands were characterised by a high share of zoophagous, mycetophagous, and saproxylic species. In contrast, managed stands were characterised by a high share of xylophagous beetles.

Gnathotrichus materiarius is listed as an alien ambrosia beetle in European fauna. This is an invasive species from North America, which was found in Europe (France) in the 1930s. In Poland, it was recorded in 2015. Already in 2017 numerous infestations of G. materiarius on lying Pinus sylvestris wood were obsereved. G. materairius is a xylomycophagous species and wood damage to its feeding is similar to that caused by striped ambrosia beetle Trypodendron lineatum. The paper presents sites of G. materairius occurrence found in 2016 and 2017. These include 15 sites located in managed forests (5 forest districts) as well as in 2 national parks situated along south-western border of Poland. G. materairius beetles were found in pheromone-baited traps used to monitor Ips duplicatus and I. amitinus or collected from infested Scots pine wood. The paper presents the description and characteristics of wood damage due to G. materiarius as well as its distinguishing features.

Gnathotrichus materiarius (Fitch, 1858) is an alien ambrosia beetle from North America, that has been spreading across Europe since the 1930s. The species infests coniferous trees, excavating galleries in sapwood. However, to date very few studies have predicted changes in ambrosia beetle habitat suitability under changing climate conditions. To fill that gap in the current knowledge, we used the MaxEnt algorithm to estimate areas potentially suitable for this species in Europe, both under current climate conditions and those forecasted for the years 2050 and 2070. Our analyses showed areas where the species has not been reported, though the climatic conditions are suitable. Models for the forecasted conditions predicted an increase in suitable habitats. Due to the wide range of host trees, the species is likely to spread through the Balkans, the Black Sea and Caucasus region, Baltic countries, the Scandinavian Peninsula, and Ukraine. As a technical pest of coniferous sapwood, it can cause financial losses due to deterioration in quality of timber harvested in such regions. Our results will be helpful for the development of a climate-change-integrated management strategy to mitigate potential adverse effects.

The Juniperus phoenicea complex consists of three taxa: J. phoenicea sensu stricto (s.s.), J. turbinata, and J. canariensis. A review of the literature on the biology of these taxa was conducted, focusing on taxonomy with paleo-data, structure, and geographical distribution to present current knowledge on these topics. Information on ecology, disease, utilization, and conservation will be presented in forthcoming parts of this monograph. Each of the three species included in the J. phoenicea complex is a monoecious or sometimes dioecious, evergreen gymnosperm with scale leaves when adult. The morphological differences between them are minor and mainly quantitative. This enables separation of taxa using a combination of traits. However, genetic features such as isozymes and nuclear microsatellites allow adequate differentiation from each other. Juniperus phoenicea s.s. occurs in the western part of the Mediterranean region, J. turbinata is circum-Mediterranean, while J. canariensis exists only on the Canary Islands, except Lanzarote and Fuerteventura, and on the Madeira archipelago. All species contain volatile oils which are used as traditional remedies for many various human and animal diseases, primarily in African and Asiatic countries. The published information for these topics is reviewed.

Gnathotrichus materiarius Fitch, 1858 is an invasive bark beetle that colonizes conifers and has spread widely in Europe. The beetle was introduced from North America to Western Europe, where it was first detected in France in 1933. In countries of Western and Northern Europe, the first detections were found at ports or airports, which probably served as sources of further spread. Gnathotrichus materiarius spread eastward to the Czech Republic and other countries in Central Europe from Germany and Poland and spread northward from Italy to Slovenia. The presence of wilting spruces, outbreaks dominated by Ips typographus Linnaeus, 1758, and the subsequent transport of timber have probably accelerated the spread of G. materiarius. It is possible that G. materiarius was imported with timber to Austria, the Czech Republic, and Poland. Although G. materiarius has been present in Europe for almost 100 yr, and even though its host trees include Picea and Pinus spp., which are abundant in Central European forests, no significant damage caused by this beetle has been detected or reported. Gnathotrichus materiarius is a typical secondary pest in that it multiplies on decaying trees or trees already infested and killed by other bark beetle species. It has 2 generations a year in Central Europe. The beetles of G. materiarius occur the whole year, but the flight of adults starts in early May and the offspring beetles emerge in mid-July. The adults of F2 generation overwinter in wood. The best method for monitoring and detecting the presence of G. materiarius is the use of ethanol-baited traps.