About Bidens subalternans DC.
Bidens subalternans DC. is a newly naturalized exotic species in Umbria. In Panicale, Perugia, near the inhabited center of Panicale (UTM WGS 84: 33 T 263.4768), on the rural road margin, with calcareous soil at 440 m, it was collected on 24 Nov 2015 by F. Falcinelli (APP). In Trevi, Perugia, near the inhabited center of Manciano (UTM WGS 84: 33 T 317.4752), on the roadside, with calcareous soil at 480 m, it was collected on 2 Dec 2015 by F. Falcinelli (APP). In Italy, it is considered naturalized in Lombardia, Liguria, Marche, and Campania, and invasive in Friuli Venezia Giulia (Conti et al., 2005; Croce & Scopece, 2006; Celesti Grapow et al., 2009 a; Marchetti, 2012).
