No abstract

Here we consider 274 alien Coleoptera species belonging to 41 of the 137 beetle families in Europe (Cerambycidae, Curculionidae sensu lato, Chrysomelidae sensu lato and Coccinelidae are treated separately elsewhere). Among the families we consider as having invaded the European fauna, Acanthocnemidae and Ptilodactylidae represent new arrivals. Many species-rich families have surprisingly few aliens, whereas some relatively minor families such as Dermestidae, Nitidulidae and Anobiidae have a relatively high representation of alien species. Since the start of the 19th century, the number of coleopteran aliens introduced into Europe has continued to increase. Alien species colonizing Europe derive from a wide range of geographic regions as well as ecozones, but the most important source area is Asia. Th e countries with the largest number of alien species established are France, Germany and Italy. Th e majority have been introduced accidentally via international transport mechanisms. Th e most important route for importation is stored products and crops, followed by transport of wood, then horticultural and ornamental plants. Most alien species in these families are found within anthropogenic habitats in Europe. Th e introduction of invasive alien beetles in these families has had signifi cant economic impacts, particularly as pests of stored foodstuff s, as well as serious ecological impacts. For example, the buprestid species Agrilus planipennis, recently recorded in Russia, is an important potential economic threat which may also impact the biodiversity associated with ash trees.

Carbon radicals from allyl O-(trimethylsilyl)-alpha-bromo-alpha,alpha-difluoroacetal can cyclize onto the olefinic part regiospecifically to give gamma-lactols in good yield. The lactols are then converted to the corresponding alpha,alpha-difluoro-gamma-lactones. Systematic synthesis of multifluorinated-alpha,alpha-difluoro-gamma-lactones has thus been accomplished through intramolecular radical cyclization as a key reaction. Semiempirical MO calculation study suggested a unique nature of alpha,alpha-difluoroacetate in that complete delocalization of the electrons in the SOMO orbital of alpha,alpha-difluoroacetyl radical occurred; this caused unsuccessful cyclization. To apply the present radical reaction, the first synthesis of both enantiomers of difluoroeldanolide, analogues of the sex pheromone of the male African sugarcane borer, has been demonstrated. Electrophysiological tests revealed that the difluorinated analogues were as active as the natural eldanolide on the olfactory receptors.

Male American palm weevils (APWs),Rhynchophorus palmarum (L.) produced two sex-specific compounds, which were disclosed by volatile collections on Supelpak-2 and gas chromatography. One was a minor compound, not always detected. The major male-produced volatile was identified as (2E)-6-methyl-2-hepten-4-ol through coupled gas chromatography-mass spectrometry and gas chromatography-Fourier transform infrared spectrometry, proton nuclear magnetic resonance spectrometry, and rational synthesis. We propose the trivial name rhynchophorol for this new molecule, which proved to be the essential component of the APW aggregation pheromone by electroantennography, coupled gas chromatography-electroantennography and behavioral bioassays.