%0 Journal Article
%T Temporal origins and diversification of Artemisia and allies (Anthemideae, Asteraceae)
%A Sanz
%A M.
%A Schneeweiss
%A G. M.
%A Vilatersana
%A R.
%A Vall豕s
%A j.
%J Collectanea Botanica
%D 2011
%I Consejo Superior de Investigaciones Cient赤ficas
%X Temporal origins and diversification of Artemisia and allies (Anthemideae, Asteraceae).- To assess temporal origins and diversification of lineages within subtribe Artemisiinae and Artemisia group a penalized likelihood analysis was applied on nrDNA ITS and ETS of 63 representatives. The tree was calibrated at the stem node of the Kaschgaria/ Artemisia lineage with the most reliable early Artemisia fossil pollen record from Late Oligocene (23 Ma). The results from this study suggest that the origin of the subtribe goes back to the Late Oligocene (24.6 ㊣ 2.6 Ma) whilst the onset of differentiation of the genus Artemisia and most closely related genera is dated to the Early Miocene (19.8 ㊣ 2.3 Ma). Divergence ages for lineages within the Artemisia group are often between the Early and Middle Miocene, whereas their radiations mostly occurred in the Late Miocene and Pliocene. The temporal context was also used to examine biogeographic and morphological (capitula and pollen type) evolution. Within the Artemisia group all lineages except the North American endemic have colonized the Mediterranean Basin at different epochs from Asian ancestors. Our analyses suggest the divergence of the North American endemic group from Asian ancestors (10.8 ㊣ 1.5 Ma) in the Late Miocene Homogamous-discoid capitula, characteristic of subgenera Seriphidium and Tridentatae, evolved not only in different geographic regions, but also at different times (2.0 ㊣ 0.8 Ma and 7.9 ㊣ 0.9 Ma respectively) within the Artemisia group. The loss of fertility of central flowers of disciform capitula should be considered as an ancient event in the genus since subgenus Dracunculus is one of the first groups that diverged (17.6 ㊣ 2.1 Ma). Evoluci車n temporal y diversificaci車n en Artemisia y g谷neros relacionados (Anthemideae, Asteraceae).- Con el objetivo de estimar el tiempo de diversificaci車n de los linajes de la subtribu Artemisiinae y el grupo Artemisia se aplic車 un an芍lisis de verosimilitud penalizado en base a las secuencias de ADNrn, ITS y ETS, de 63 representantes. El 芍rbol se calibr車 en el nodo del linaje de Kaschgaria/Artemisia con el polen f車sil de Artemisia que se consider車 m芍s fiablemente datado, siendo esta dataci車n del Oligoceno Superior (23 Ma). Los resultados de este estudio datan el origen de la subtribu en el Oligoceno Superior (24,6 ㊣ 2,6 Ma), mientras que la diferenciaci車n del g谷nero Artemisia y los g谷neros relacionados es datada en el Mioceno Inferior (19,8 ㊣ 2,3 Ma). El tiempo de divergencia de los linajes dentro del grupo Artemisia est芍 situado entre el Mioceno Inferior y el M
%K Anthemideae
%K Artemisia
%K Artemisiinae
%K Biogeograf赤a
%K Compositae
%K Dataci車n molecular
%K Evoluci車n morfol車gica
%U http://collectaneabotanica.revistas.csic.es/index.php/collectaneabotanica/article/view/180/182