Authors: Omar FizPalacios Virginia Valcarcel
Publish Date: 2011/05/31
Volume: 295, Issue: 1-4, Pages: 109-118
Abstract
The Daisies Bellis and Bellium form a monophyletic complex within the core Astereae Asteraceae Although most early diverging lineages show an African distribution the core Astereae is today widespread on five continents with the Bellis/Bellium complex as the only representative in the Mediterranean basin Molecular clock estimates placed the divergence of Astereae from its sister tribe Anthemideae in the Oligocene Using a combination of three plastid genes we estimated divergence times for different lineages of the tribe Astereae This together with temporal and biogeographical reconstructions using the nrITS region allows placing and timing of the major lineages of the Bellis/Bellium complex The age reconstruction places the divergence of the tribe Astereae in the late Miocene 18–19 million years ago followed by an outofAfrica dispersal into Asia where the worldwide expansion may have started Our results suggest that the colonization of the Mediterranean basin by the Astereae started from Eurasia some 10 million years ago A Messinian early divergence of the Bellis/Bellium complex in the Mediterranean was estimated However a parallel 4millionyear delay for the withingenera diversification was inferred probably related to the establishment of the sclerophyllous Mediterranean forest Despite a similar time frame for the withingenera diversification today’s species numbers differ considerably between Bellis 15 spp and Bellium five sppWe thank P Vargas for his help with phylogenetics and taxonomy H Schaefer for helpful discussion J Aldasoro for field assistance and G Atkinson for help with the manuscript This research was partly supported by the Spanish Ministry of Education and Culture through the project REN200304397
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