Wolffia globosa (Araceae s. l. / Lemnaceae s. str.), a new aquatic alien species in the flora of Ukraine

Abstract

In Europe, Wolffia globosa was first recorded in 2002 in the RF, and not in Bulgaria, as it was previously believed. Over the past 20 years, the species has expanded its secondary range. As of 2023, it is known from seven European countries. In Ukraine, W. globosa was first found in 2023 in two localities in Zhytomyr Region (Zhytomyr Polissia). The plant communities with W. globosa in Ukraine belong to the association Lemno-Spirodeletum polyrhizae of the alliance Lemnion minoris of the class Lemnetea. In the reported localities W. globosa occurs in eutrophic stagnant waterbodies with depths of 0.2–0.5 m and weakly flowing waterbodies with depths of 1.2–1.5 m; silty bottom is covered by a silt layer 5–20 cm thick, lighting is full. It is suggested that due to the observed climate warming, further migrations of W. globosa to other regions of Ukraine are possible.