First record of non-native Asian seed beetle, Megabruchidius dorsalis (Fåhræus, 1839) and its parasitoid, in Slovenia

Abstract

This contribution serves to formally report the first record of the non-native Asian seed beetle Megabruchidius dorsalis in Slovenia, found in 2017 and 2018 in Maribor. Within the range known at present in Europe this species has found a new food source - the seeds of the ornamental North American tree species Gleditsia triacanthos. From seeds collected in autumn of 2017 adult beetles emerged in the spring of 2018. Later in 2018, seeds in pods, which overwintered and were kept outdoors in summer, were collected in the beginning of autumn. Fully developed beetles were found and the inspection of 500 seeds showed heavy infestation from various life-stages, sometimes co-occurring, indicating that the multivoltine life cycle has been retained in the new range. Additionally, in two of seven locations both live and dead Hymenoptera parasitoids inside the pods with damaged seeds and beetle remains were observed.