Abstract
New Italian populations of Knautia dinarica, formerly known only for Sila (Calabria, Southern Italy), were discovered in Abruzzo (Central Italy) and Basilicata (Southern Italy). In order to correctly classify these populations, a taxonomic study was carried out, including morphological and karyological analyses and the typification of the names Knautia sylvatica var. dinarica and K. arvensis f. silana. We conclude that in Italy only K. dinarica subsp. silana occurs, to be considered as endemic to central-southern Apennines and vicariant of K. dinarica subsp. dinarica, occurring in the Balkan peninsula. Both subspecies can be either diploid (2n = 20) or tetraploid (2n = 40), and are distinguished by the different mean shape of the basal leaves (the ratio length/width is higher in Italian plants).