Recent distribution and phytosociological affiliation of Ludwigia palustris in Slovakia

Abstract

Ludwigia palustris has always been a very rare species in Central Europe. In Slovakia, its occurrence remained unconfirmed for over 60 years and it was therefore considered extinct. Te paper reports its rediscovery on two sites in SE Slovakia. Both localities were found in the Latorica River catchment area in 2015 when persistent summer droughts enabled the development of natural mudflat vegetation in the dried oxbows. Confirmation of this historic site indicates the long-term survival ability of the species. We assigned L. palustris dominated vegetation in the class Isoëto-Nanojuncetea, association Ludwigio palustris-Lindernietum procumbentis. Tis association is new to Slovakia as well as for Central Europe. Te stands of this association developed on the exposed muddy shores of disconnected oxbow lake.