Diversification patterns of the CES clade (Tribes Cremolobeae, Eudemeae, Schizopetaleae: Brassicaceae) along Andean South America.

DIEGO L. SALARIATO; FERNANDO O. ZULOAGA; ANDREAS FRANZKE; KLAUS MUMMENHOFF; IHSAN AL-SHEHBAZ

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2016 vol. 181 p. 543 - 566

0024-4074

Dated molecular phylogenies show that the Andean uplift had a major impact on South American biodiversity. For many Andean groups, accelerated diversifications (radiations) have been documented. However, not all Andean lineages appear to have diversified following the model of rapid radiation, particularly in the central and southern Andes. Here, we investigated the diversification patterns for the largest South American-endemic lineage of Brassicaceae, composed of tribes Cremolobeae, Eudemeae, and Schizopetaleae (CES clade). Species of this group inhabit nearly all Andean biomes and adjacent areas such as the Atacama-Sechura desert, the Chilean Matorral, and the Patagonian Steppe. First, we studied diversification times and historical biogeography of the CES clade. Second, we analysed diversification rates through time, lineages, and associated life forms. Results demonstrate that early diversification of the CES clade occurred in the Early-Mid Miocene (around 12?19 Mya) and involved the central Andes, the southern Andes together with the Patagonian Steppe, and the Atacama-Sechura desert. The Chilean Matorral and northern Andes were colonised subsequently in Early Pliocene (4?5 Mya). Diversification of the CES clade was recovered as a gradual process without any evidence for rate shifts or rapid radiation, in contrast to many other Andean groups analysed so far. Diversification time/rates and biogeographic patterns obtained for the CES clade are discussed and compared with patterns and conclusions reported for other Andean plant lineages.