Tribe Eudemeae comprises a morphologically heterogeneous group of genera distributed along the Andes of South America from Colombia southward into southern Chile and Argentina. The tribe currently includes seven genera: Aschersoniodoxa, Brayopsis, Dactylocardamum, Delpinophytum, Eudema, Onuris, and Xerodraba, and exhibits a wide morphological diversification in growth habit, inflorescences, and fruits. However, little is known about the phylogenetic relationships and evolution of the tribe. We present here a molecular phylogeny of representative sampling of all genera, utilizing sequence data from the nuclear ribosomal ITS region and chloroplast regions trnL-F, trnH-psbA, and rps16. Additionally, climatic niches of the tribe and its main lineages, along with the evolution of diagnostic morphological characters, were studied. All analyses confirmed the monophyly of Eudemeae, with the exception of Delpinophytum that was included with genera of the lineage I of Brassicaceae. Eudemeae is divided into two main lineages differentiated by their geographical distribution and climatic niche: the primarily north-central Andean lineage included Aschersoniodoxa, Brayopsis, Dactylocardamum, and Eudema, and the Patagonian and southern Andean lineage included Onuris and Xerodraba. Finally, ancestral-state reconstructions in the tribe generally reveal multiple and independent gains or losses of diagnostic morphological characters, such as growth form, inflorescence reduction, and fruit type. Relevant taxonomic implications stemming from the results are also discussed.
Bibliographical noteFunding Information:
Funding of this work was provided by ANPCyT (Agencia Nacional de Promoción Científica y Tecnológica) Grant PICT- 2013-1042 , CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas) Grants PID 11220100100207, PIP 11220100100155, and D4541-12, and the National Geographic Society Grants 8365-07 and 8862-10, for which we are profoundly grateful. Fieldwork and visits to herbaria were supported by the Myndel Botanical Foundation grants in 2010, 2011, and 2012. Asunción Cano is also grateful for funding from the National Science Foundation grant to Kenneth Young (CNH # 1010381 ). Funding to Al-Shehbaz to visit herbaria was supported by the US NSF Grant DEB-1252905 , for which he is prfoundly grateful. We especially appreciate the help of the Associate Editor Jocelyn Hall and two anonymous reviewers who provided useful suggestions to improve an early version of this paper. We are also profoundly grateful to the directors, curators, and collection managers of the visited herbaria. We also thank E. Navarro, H. Trinidad, C. Ulloa, and C. Zannoti for the photographs used in this work.
- South America