Molecular phylogenetics and historical biogeography of <i>Mansoa</i> DC. (Bignonieae, Bignoniaceae)

Abstract The Neotropics are well known for their exceptionally rich biodiversity, likely linked to the dynamic geological and climatic history of the region. The origin of such high diversity is best explored through comprehensive species-level phylogenies of lineages endemic to the region. The plant family Bignoniaceae includes c. 850 species, nearly half belonging to the tribe Bignonieae, the largest clade of neotropical lianas. The lianescent genus Mansoa is one of the 20 genera included in the tribe. The genus is widespread throughout the Neotropics and previous studies support the inclusion of 18 species. Mansoa is distinguished by both its strong garlic scent and showy magenta flowers. Sampling included 15 species and 30 individuals of Mansoa. We reconstructed a comprehensive time-calibrated phylogeny of the genus using both a combined dataset composed of targeted loci data generated through Sanger sequencing and high-throughput plastome data generated through genome skimming. Mansoa and most of its species are recovered as monophyletic, except for Mansoa angustidens and Mansoa hirsuta, which appeared as paraphyletic. We reconstructed the ancestral range and dispersal history of the genus, which was estimated to have an Amazonian origin during the Late Oligocene and Early Miocene, a time defined by the formation of the Amazonian lacustrine systems, including the Pebas and Acre systems. More recent diversification of the group was influenced by further climatic and landscape changes from the Miocene to the present, triggered by the Andean orogenesis. Our study sheds new light on the history of the Neotropical flora, highlighting the importance of species-level phylogenies for our understanding of the biogeographic history of the Neotropics.