Phylogenetic analyses of nrITS sequences of Asteraceae revealed that the Bellis group
is a natural assemblage comprising all the species of Bellis and Bellium, but not
Rhynchospermum. In contrast, we propose to include the genera Bellis, Bellium, and
Bellidastrum in the subtribe Bellidinae in the interest of circumscribing natural
groups. Our results also suggest an early diversification in the western Mediterranean
Basin of two monophyletic lineages, Bellis and Bellium. Three major groups can be
distinguished within BELLIS: (1) the B. perennis group, containing five annual and
perennial species with three ploidy levels (diploid, octoploid, and decaploid), which
are distributed throughout the Mediterranean Basin despite lack of pappus; (2) the
Bellis sylvestris group, with five annual and perennial species primarily from the
western Mediterranean, in which there are five ploidy levels (diploid, tetraploid,
hexaploid, octoploid, and decaploid); and (3) a basal grade consisting of three diploid,
perennial species which displays remarkable diversification of morphologies. Striking
characteristics, such as an annual life form, polyploidy, and loss of pappus, seem
to have occurred in parallel several times and in different geographical areas during
the early diversification of Bellis species in the western Mediterranean. Character
evolution reconstructions allow us to describe a putative ancestor of the genus Bellis
(proto-Bellis).