The northernmost findings of the Alcathoe bat (Myotis alcathoe von Helversen & Heller, 2001) in Poland

Abstract

The Alcathoe bat Myotis alcathoe (von Helversen, Heller, 2001) is a newly described species of the cryptic complex of whiskered bat species living in sympatry across Europe. The habitats preferred by this species are natural, moist and deciduous forests with old trees and water streams. The majority of known locations of this species come from highlands, foothills and mountainous regions while practically not occurring in the lower elevations. They come mainly from cave areas, where bats were caught during autumn swarming, while records in other seasons are much less frequent. Currently, individual sites in Poland also come from lowlands, beyond the range of the mountains and uplands, which indicates a possible wider range of this species. The bats were captured using mist-nests in the Silesian Lowlands for three consecutive years (2013–2015). The localities were placed in various forest environments, ranging in elevation from 100 to 260 m a.s.l. Bats were initially identified based on morphological features, then the correctness of identification was confirmed by molecular methods. Two females and five males of Myotis alcathoe were captured into four new locations from the lowlands of Poland: Przemków, Głębowice, Chodlewo, and Dalkowskie Jary (Silesian Lowland). Old trees and a small watercourse were important elements in all these locations. Currently, these findings are the northernmost locations of the species in Poland and one of the northernmost locations in Central Europe. The latest findings of the species are located about 50 km to the south, but the vast majority of the rest of locations is from the foothills belt. This finding suggests that the species may inhabit regions much further north than previously suggested, and the limiting factor is the presence of old trees in wet environments.