Contribution to the Knowledge of Leontodon Sect. Asterothrix (Cass.) Ball in Italy and on the Balkan Peninsula

In order to better understand the Leontodon crispus group within L. sect. Asterothrix, we collected specimens belonging to this group during several journeys to the Apennines and the Balkan Peninsula, especially to Croatia, Albania, and Greece. In the present contribution, Leontodon biscutellifolius is lectotypified; the locus classicus of this taxon is located in the Abruzzo Mts (central Italy). As a consequence, the taxon is confirmed for the Italian flora (central and southern Apennines) and a new combination on variety rank is proposed: L. crispus var. biscutellifolius. Plants from the Balkan Peninsula, currently named L. biscutellifolius, were compared from a morphological point of view with the Apennines populations. Balkan populations show denser indumentum on the leaves, usually consisting of 4-fid hair vs. usually 3-fid hairs in the Apennines. Additionally, the ray number of marginal hairs on the external involucral bracts was found to be 3–5 in the Apennines vs. 4–6 in the Balkan Peninsula accessions. Morphological variation was found to be in correspondence with a variation in genetic respects based on DNA-based fingerprinting (AFLPseq). The oldest subspecific name that can be used for Greek and Albanian populations is L. crispus subsp. asper. A morphologically and genetically deviating population from Southern Pindus (Greece) is described here as L. hellenicus subsp. valeriae.