Lupinus sect. Albus (Fabaceae): Taxonomic criticism and conservation value. The case of wild populations in central Italy

Taxonomy and distribution of Lupinus L. sect. Albus are discussed and updated with new data from Italy. The study of natural populations of Lupinus in the central Tyrrhenian Italy was based on the observations (in situ and ex situ) of the combination of the diagnostic characters (colour of corolla and seeds) mainly used by other authors, as well as the dehiscence of the pods, the dimension, shape and permeability of the seeds, according to the agronomic and genetic studies widely reported in the literature, to discriminate between the wild form (Lupinus albus subsp. graecus) and those escaped from cultivation (L. albus subsp. albus). Our results (1) led us to confirm the rank of subspecies to the wild form, L. albus L. subsp. graecus (Boiss. & Spruner) Franco & P. Silva, (2) confirm the presence of hybrids forms in Italy and (3) update the distribution area of subsp. graecus in Italy, including Apulia (Gargano). L. albus subsp. graecus can be considered as a flag species of the interesting form of the edaphophilous steppe, rare in central Italy, confirming its value as an indicator of habitat naturality.