First report of Nematus tibialis in Slovenia
The NPPO of Slovenia recently informed the EPPO Secretariat of the first record of Nematus tibialis (Hymenoptera: Tenthredinidae – locust sawfly) on its territory. A single larva was found in one location (Tivoli park in Ljubljana) but characteristic injuries on Robinia pseudoacacia leaves were also observed in several places in Slovenia. This insect makes characteristic holes in the leaves (larvae preferably eating the center of the leaf), causing only aesthetic damage. The larva and damage had been discovered by chance by a professional entomologist. The identify of the pest was confirmed by the official laboratory of the Slovenian Forestry Institute. The most likely origin of the introduction of N. tibialis into Slovenia is natural spread from neighbouring countries. No official phytosanitary measures will be taken.
The pest status of Nematus tibialis in Slovenia is officially declared as: Present, at low prevalence.
EPPO note: N. tibialis is a North American species developping on R. pseudoacacia which has been introduced into several European countries (e.g. Austria, Belgium, Bulgaria, Croatia, Czech Republic, Germany, Finland, France, Greece, Hungary, Italy, Lithuania, Moldova, Netherlands, Poland, Romania, Serbia, Slovakia, Spain, Switzerland, Ukraine, United Kingdom).
Pictures of N. tibialis can be viewed on the Internet:
https://www.invasive.org/browse/subthumb.cfm?sub=7066&host=3350
https://sl.wikipedia.org/wiki/Robinijeva_grizlica
Sources
NPPO of Slovenia (2018-04).
INTERNET
DAISIE. http://www.europe-aliens.org/speciesFactsheet.do?speciesId=50671#
Fauna Europaea. https://fauna-eu.org/cdm_dataportal/taxon/49efc2ce-6878-42a3-be1a-6b0828c3482b