Insights into the Tribe Duranteae (Verbenaceae): A molecular phylogenetic approach to the systematics of the New World genus Duranta L.

MORONI, PABLO; O'LEARY, NATALY

Ohio

Conferencia; BOTANY2020; 2020

Botanical Society of America

The Neotropical region has intrigued scientists since the first explorations, and will most probably continue to do so for years to come. Plant diversity in this area has been a challenge, especially for taxonomically complex and diverse genera such as Duranta L. This genus is the second largest clade from Duranteae, after Stachytarpheta, and comprises a notable element in tropical and subtropical zones of the New World. It includes shrubs and small trees widely distributed from southern North America and the Caribbean to northern Argentina in South America. Since Linnaeus erected Duranta, studies on the genus have so far been largely restricted to partial taxonomic treatments based on morphological data. Duranta has not been rigorously tested in a phylogenetic context and so we here present the results of a phylogenetic analysis based on data from two plastidic (psba-trnh and trnL-F) loci and one nuclear (ETS) locus for twenty Duranta samples that represent about two-thirds of its known diversity. This research aimed to (1) test the monophyly of Duranta; and (2) elucidate the phylogenetic relationships within the genus. The molecular analysis strongly supports the monophyly of Duranta in its current circumscription, its position within Duranteae tribe, and provides the basis for addressing some taxonomical problems and inferring the ancestral area of distribution. Diversification of Duranta seems to have taken place in the Central Andes of the Americas, with its distribution being shaped by the geologically defined structural units of the Andes. The crown estimated divergence time for the genus Duranta is set in the late Miocene. In this framework, we posit that the uplift of the Andes led to the diversification of lineages in the New World, in which different species radiated and colonized new environments. This work will be of great help to botanists in the Americas, and will hopefully stimulate interest in the study and conservation of these plants.