Lycopus lucidus Turcz. ex Benth. var. hirtus Regel (Lamiaceae) in Italy: a new naturalized alien species for the European flora.
Lycopus lucidus Turcz. ex Benth. var. hirtus Regel (Lamiaceae), a neophyte native to Asia, is recorded for the first time in Europe. A naturalized population was discovered in the Milan railway area (Italy). Diagnostic characters and an updated identification key for the genus Lycopus in Europe are presented. Furthermore, the invasive status and the possible means of introduction are discussed.