New records of the invasive species Megachile sculpturalis, Smith, 1853 in Ukraine

Abstract

Background. Biological invasions are one of the recognized causes leading to the loss of native diversity. Among wild bees in Europe, only three invasive species are known, one of them being Megachile (Callomegachile) sculpturalis Smith, 1853 (Hymenoptera: Megachilidae) – the rapidly spreading giant resin bee whose impact on local diversity remains unexplored. Not only scientists, but also many naturalists are involved in monitoring this invasive species in Europe. The unique appearance of this species and the lack of similar species in the family Megachilidae in Europe makes it easy to identify it even by photo. This oriental species was first recorded in Europe in 2008, in Ukraine in 2018. The aim of our work was to study the distribution of M. sculpturalis in Ukraine and some features of its ecology. Material and Methods. The object of the study is the alien species of wild bees Megachile sculpturalis. For data analysis, we used records of amateur naturalists and their photographic evidence, as well as our own collection material. Insects were identified using binocular stereoscopic microscope Olympus SZX 12 and specialized keys. Results. The article presents analysis of records of the invasive species M. sculpturalis in Ukraine. Five new sites of its distribution were revealed: in the territory Zaporizhzhia region (Zaporizhzhia, Khortytsia island), Odesa region (Odesa, Chornomorsk, Kuyalnytskyi estuary) and Mykolaiv region (Mykolaiv). This allowed us to change the chronology of its settlement in Ukraine and expand the map of its distribution. Bees exhibited relative ecological plasticity when choosing nesting sites, and consistency of nesting cavities recolonization. Conclusions. Data analysis and observations have shown that the alien species M. sculpturalis was brought to Ukraine repeatedly and in different places, which enables it to establish itself in the secondary habitat, form viable offspring and successfully reproduce. Our study also shows the importance of citizen science and the importance of actively involving amateur naturalists in monitoring invasions.