On the genuine identity of Hieracium amplexicaule (Asteraceae) in Belgium and neighboring territories

The xenophyte Hieracium amplexicaule s.l. has been known since at least 1867 from the surroundings of Tongeren (Belgium) and Maastricht (the Netherlands). Its populations have been attributed to both H. amplexicaule s.str. and H. speluncarum. A critical review of the herbarium samples, including the type material of the relevant taxa, has shown that these populations belong to yet another species, H. pulmonarioides. Other populations, more recently discovered (e.g. in northern France), also belong to this (micro-)species. Hieracium amplexicaule s.str. does not exist in the territory of the Nouvelle Flore de la Belgique.