Recent and local diversification of Central American understorey palms

Aim Central America is largely covered by hyperdiverse, yet poorly understood, rain forests. Understorey palms are diverse components of these forests, but little known about their historical assembly. It not clear when in reached present diversity levels and whether most species arrived from neighbouring regions or evolved locally. We addressed questions using the species-rich American palm clades indicative reconstructed compared phylogenomic biogeographical history with diversification 54 other plant lineages, to gain a better understanding processes that shaped assembly Location America. Time period Cretaceous present. Major taxa studied Arecaceae: Arecoideae: Bactridinae, Chamaedoreeae, Geonomateae. Methods sampled 218 through fieldwork living collections. sequenced genomic DNA target sequence-capture procedures. Using 12 calibration points, we dated phylogenies under three approaches (multispecies coalescent, maximum likelihood Bayesian inference), conducted analyses (dispersal–extinction–cladogenesis) estimated phylogenetic metrics. Results Dated revealed intense Ma. Local events were four times more frequent than dispersal events, found strong clustering relationship Main conclusions Our results suggest understorey characterize forests today locally after repeated mostly South diversified primarily closure Seaway at c. 13 Ma, suggesting Great Biotic Interchange was major trigger for This recent contrasts much earlier existence forest since 58 similar timings seed an unexpectedly hyperdiverse flora.