Xylocopa valga Gerst. (Hymenoptera: Apidae) in Poland

In this article, we review the distribution and new data on the occurrence of Xylocopa valga Gerst. (Hymenoptera: Apidae) in Poland. This is also the first report of X. valga occurring in the Białowieża Forest, where it was captured visiting flowers of Lychnis flos-cuculi L. in a sandy grassland adjacent to the forest in the vicinity of Grudki, a small village near Białowieża. All 15 known records of this species in Poland are compiled into a detailed list, and the location of each sighting is presented on the map. In two cases, the known distributional data have been corrected and were brought up to date. The first case is a forgotten record of the species (Popov 1947) that was reconstructed based on museum specimens collected in the 1870s at Karolath, Silesia (formerly Germany, currently Poland: locality now named Siedlisko), and this record was added to the list. However, the second case concerns a record from Tuchla near Jarosław (Banaszak 1989), which was excluded from the list because it had been published as a result of misinterpretation of the label on the old museum specimens. Information on the species’ biology, especially on the preferred habitats and nesting in dead wood, are also presented. X. valga is regarded as a saproxylic species occurring in forests, but its ability to inhabit the steppe zone is also discussed in this article. Furthermore, a list of flowering plants (95 species representing 30 families) visited by this bee species has been prepared based on the data from the literature as well as our own observations. The new record of X. valga in the Białowieża Forest in combination with the recent data from Western Europe suggests that this subpontic-mediterranean species is expanding its natural range probably due to climate change. We are thus also discussing its potential to spread further north