Update on the situation of Euwallacea fornicatus sensu lato in Europe
A recent article by Schuler et al. reviews the recent findings of Euwallacea fornicatus sensu lato (Coleoptera: Scolytinae, EPPO A2 List) in tropical greenhouses in Europe and the eradication measures applied. A comparative genetic analysis of insects from different locations in Europe was performed to trace back the introduction pathway of these beetles in Europe. In addition, several NPPOs have recently reported successful eradication of outbreaks detected in tropical greenhouses.
Euwallacea fornicatus sensu lato was found in greenhouses in Poland (EPPO RS 2019/030), in Italy (RS 2020/094), in Germany (RS 2021/033, RS 2021/059) and in the Netherlands (RS 2021/078, RS 2022/082). The outbreaks in Poland, Italy and the Netherlands are now eradicated. In Germany, the outbreak in Erfurt is eradicated, and the one in Berlin is still under eradication as beetles were still trapped in September 2022. Trace back investigations showed that infested host plants had been imported through the Netherlands, but infestation was only detected several months after they had been planted.
Molecular analyses of the beetles showed that individuals from Poland and Italy are genetically identical and belong to a different mitochondrial clade to individuals in Germany. The specimens from Germany were identical to most individuals from two greenhouses in the Netherlands. However, in the two greenhouses in the Netherlands some beetles belonged to another haplotype of E. fornicatus and to two haplotypes of E. perbrevis, a species in the E. fornicatus complex which had not previously been detected in Europe. The finding of several haplotypes from various geographic regions highlighted that both Euwallacea species had likely been introduced by multiple introduction events.
In the infested greenhouse in Italy, a total of 28 trees of 21 different species (Annona muricata, Artocarpus heterophyllus, Averrhoa carambola, Bixa orellana, Bulnesia arborea, Cananga odorata, Clausena lansium, Crescentia cujete, Debregeasia edulis, Dimocarpus longan, Ficus altissima, Ficus sp., Justicia sp., Kigelia africana, Melicoccus bijugatus, Magnolia champaca, Millettia brandisiana, Persea americana, Terminalia catappa, Terminalia buceras, Theobroma cacao) showed boreholes and ejection of wooden debris. Most of them were not yet recorded as hosts elsewhere.
The pest status of Euwallacea fornicatus sensu lato in Italy is officially declared as: Absent, pest eradicated.
The pest status of Euwallacea fornicatus sensu lato in the Netherlands is officially declared as: Absent, pest eradicated.
The pest status of Euwallacea fornicatus sensu lato in Germany is officially declared as: Present, only in some parts of the Member State concerned, only in greenhouse, under eradication.
Sources
Schuler H, Witkowski R, van de Vossenberg B, Hoppe B, Mittelbach M, Bukovinszki T, Schwembacher S, van de Meulengraaf B, Lange U, Rode S, Andriolo A (2022) Recent invasion and eradication of two members of the Euwallacea fornicatus species complex (Coleoptera: Curculionidae: Scolytinae) from tropical greenhouses in Europe. Biological Invasions. https://doi.org/10.1007/s10530-022-02929-w
NPPO of Italy (2022-07).
NPPO of the Netherlands (2022-10).
NPPO of Germany (2022-10).