Latvis, Maribeth , Soltis, Pamela , Soltis, Douglas .
Biogeography and diversification shifts within Agalinis (Orobanchaceae): exploring a recent South American radiation.
Phylogenetic studies of clades from species-rich biomes provide a framework for understanding where these lineages originated geographically, how they have subsequently diversified, and how these biomes were assembled. We focus on phylogenetic relationships in Agalinis (Orobanchaceae), an angiosperm genus of ~70 species with a New Word distribution and with South American centers of diversity in two recognized biodiversity hotspots: the Andes and the Cerrado of Brazil. The broadly sampled phylogeny, generated from combined chloroplast (rbcL, matK, ndhF, rpoB, rps2, trnT-trnF, psbA-trnH) and nuclear data (ITS, PPR-AT1, PPR-AT3, PPR-AT5), reveals a pattern consistent with a rapid, recent radiation into South America. This pattern is also corroborated by estimates of divergence times within the clade, using the program BEAST. Agalinis is an ideal clade for investigating historical biogeography and diversification between North and South America and between the Andes and Cerrado. Several Brazilian species are endemic to the fragmented campos rupestres, a vegetation type within the Cerrado, the diversity of which has been underexplored phylogenetically. We discuss the historical biogeography of Agalinis based on reconstructions using RASP (S-DIVA) and the dispersal-extinction-cladogenesis likelihood model (DEC) implemented in Lagrange. We also explore putative diversification shifts in Agalinis within this biogeographic and paleoclimatic context. These results will be useful for future comparative phylogenetic studies on historical biome assembly in the Neotropics, especially those with an emphasis on the Andes Mountains and the Cerrado.
1 - Florida Museum Of Natural History, Florida Museum Of Natural History, Dickinson Hall, Museum Rd., Gainesville, FL, 32611, USA
2 - University Of Florida, Florida Museum Of Natural History, PO BOX 117800, Gainesville, FL, 32611-7800, USA
3 - University Of Florida, Department Of Botany, 220 BARTRAM HALL, Gainesville, FL, 32611, USA
Presentation Type: Oral Paper:Papers for Sections
Candidate for Awards:George R. Cooley Award