Abstract Detail

Biogeography

Scherson, Rosa Amelia [1], Moreira-Muñoz, Andrés [2], Monge, Marcelo [3], Silva, Herman [4].

Molecular phylogeny of Mutisia (Asteraceae, Mutisieae) with biogeographic implications in the Neotropical disjunction.

Mutisia L.f. is a South American genus with two disjunct distribution centers: southeastern Brazil, Uruguay, Paraguay and NE Argentina (5 species) and the Andes from Colombia to Patagonia (around 55 species), with its highest richness in Central Chile. These taxa occupy several habitats, from humid to very dry environments. Characteristic life forms are lianas, but some of them are shrubs or subshrubs. The majority has compound leaves and the capitulum is always solitary, varying in size, with the pappus being plumose. The morphology of the capitula has a strong correlation with bird pollination and the pappus morphology with wind dispersion. Angel Cabrera in 1965 proposed a division of the genus in six different sections. Characters considered as primitive by Cabrera were simple leaves, isomorphic flowers, and little capitula, among others. No phylogenetic work has been done in the genus so far, even though some sequences were available in GenBank. The aim of this work was (1) test the monophyly of Mutisia; (2) discuss the sections proposed by Cabrera on a new phylogenetic framework and (3) discuss possible implications for biogeographical interpretations. The samples included all Brazilian and most Chilean taxa, and representatives of Colombia, Peru, Argentina and Bolivia. Bayesian phylogenetic analyses were performed using the nuclear regions ITS and ETS and the chloroplast spacer trnL-trnF. The ETS region, never amplified before in Mutisia, showed a very good resolution, suggesting its usefulness to resolve relationships at low taxonomic levels within the family. Trees obtained showed congruence between cellular compartments. A well-supported phylogeny was obtained confirming the monophyly of the genus. The Eastern group showed a derived position, sister to species that are endemic to NW Argentina, Bolivia and northern Chile. Interestingly, M. lutzii appears close to the species of the Mutisia section, challenging the position proposed for the species in the Guariruma section. That means that the Eastern species show a geographic coherence not reflected in the morphology. Species distributed in Chile and Chile/Argentina show a more basal phylogenetic position, suggesting a South-North invasion of the genus in South America, with probable extinctions in between, possibly related to the tendency towards aridity accompanying the Cenozioc Andean rise. This has been one of the main causes of W-E disjunctions between the Andes and southeastern Brazil that is to be seen in many different groups within Neotropical angiosperms. Acknowledgements: Fondecyt 1150425; Conicyt 7912010011, Fondecyt 1120261

1 - Universidad de Chile, Departamento de Silvicultura y Conservación de la Naturaleza, Santa Rosa 11315, Santiago, Chile
2 - Pontificia Universidad Católica de Valparaíso, Instituto de Geografía, Valparaíso, Chile
3 - Universidade Estadual de Campinas, Graduate Program of Plant Biology, Sao Paulo, Brazil
4 - Universidad de Chile, Departamento de Producción Agrícola, Laboratorio de Genómica Funcional y Bioinformática, Santiago, Chile

Keywords:
Mutisia
Asteraceae
biogeography
Disjunction.

Presentation Type: Poster:Posters for Topics
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PBG009
Abstract ID:1145
Candidate for Awards:None