O. Merkl szerk.: Folia Entomologica Hungarica 68. (Budapest, 2007)

The species was described from Japan. The original distribution area is East and Southeast Asia (Japan, Korea and the eastern part of China). It was introduced to the USA (1932), where it was discovered in imported wine stocks in greenhouses. The species escaped and became an important pest on different woody plants (ATKINSON etal. 1990). In Europe it was first recorded after the WWII in Germany (GROSCHKE 1953). The detailed investigations figured out, that the species might be introduced with wood pieces imported from Japan to South-Germany already at the beginning of the 20 century. The species expanded its distribution area slowly to natural beach (Fagus) and oak (Quercus) stands. The present distribution area includes France, Belgium (BRUGE 1995), Germany (GROSCHKE 1953), Switzerland (MAKSYMOV 1987, GRAF & MANSER 1996), Italy (FACCOLI 2000), Austria and Russia (MANDELSHTAM 2000). Many other countries must belong to the present distribution are too, but because of the lack of adequate information no details are available. X. germanus is highly polyphagous. In its native distribution area a great variety of broadleaved and evergreen wood and shrub species can be affected (e.g. tea shrub). The host range in the introduced areas (Europe and North America) also includes many plant species, like: Quercus, Fagus, Acer, Alnus, Betula, Buxus, Carpinus, Castanea, Corylus, Ficus, Juglans, Robinia (!), Ulmus, Picea, Pinus and Abies (POSTNER 1974). The judgement of X. germanus is still controversial. The high number of possible host plants and the reported damages especially in the USA - but also in the native areas - assume a high risk also for the European forest ecosystems. However, none of the investigations supported this assumption. The species is presented in many countries for many years, but until now no considerable damage was reported from Europe. It is considered everywhere as a secondary pest, which can feed only in freshly felled logs and stumps. We have excavated also the first individuals from freshly felled oak and linden logs, and reared from attacked tree parts at the Institute of Sylviculture and Forest Protection. Genetic analyses - the comparison of the 400bp fragment of the mitochondrial COI gene - also confirmed the high similarity of Hungarian and German individuals, e.g. Xylosandrus germanus was found. Bootstrap values calculated indicate the extension of both the length of COI fragment and the number of individuals. The method should be used for species identification also in other insect taxa.