Abstract Detail

Phylogenomics

Bacci, Lucas [1], Cellinese, Nico [2], Michelangeli, Fabian [3], Judd, Walter [4], Reginato, Marcelo [5], Majure, Lucas [6].

A phylogenomics approach to resolving one of the world’s most diverse, tropical angiosperm radiations: Melastomataceae.

Melastomataceae constitute one of the major radiations within the flowering plants. It is among the top ten largest clades across the angiosperms with around 5700 known species, consisting mostly of neotropical trees and shrubs, but also including herbs, lianas and epiphytes. The drivers of such a vast and rapid diversification have not been explored comprehensively across the clade, and current datasets do not allow further investigation. Diversification in the family appears to be related with the diverse habitats in which they are found and their associated pollinators (and consequently floral morphology variation), fruit types and dispersal agents. Moreover, there are several leaf morphological and anatomical traits, a huge diversity of trichome types, and a variety of other animal-plant interactions (e.g., mite and ant-domatia), and sexual systems (e.g., perfect flowers, dioecy, outcrossing, obligate selfing, agamospermy). Other potential mechanisms for diversification, including hybridization and polyploidy (neo- and paleopolyploidy), have not been explored in a comprehensive way for Melastomataceae. Thus, this family presents an ideal system to test hypotheses about the tempo and mode of evolution in a large clade of mostly tropical, montane angiosperms. The main reason why the diversification of this worldwide group has not been adequately explored is the lack of a comprehensive and well supported phylogenetic hypothesis to act as a framework to test these phenomena. Resolving the backbone phylogeny of Melastomataceae remains a challenge mainly because of continued use of just a few plastid and nuclear loci. Therefore, we propose to generate the largest and most comprehensive phylogenomic dataset consisting of both hundreds of single-copy nuclear loci and entire plastomes, across any major, pantropical, angiosperm family. Roughly half of all known samples (ca. 2500) and all genera (ca. 188) will be sampled, covering all major clades and subclades of the family. A single copy nuclear gene bait set derived from transcriptomes of two Melastomataceae lineages was developed, including exons and intronic regions. Preliminary analyses have shown high success rates for locus retrieval of the probes developed both at deep relationship levels and likewise for resolution at the species and population level. Here we present a subset of this data, together with comparative plastomes (a total of ca. 350 samples) to exemplify how this kind of data generated by our ongoing project will be crucial to understand the diversification of the family.

1 - University Of Florida, Florida Museum Of Natural History, Herbarium FLAS, 1659 Museum Rd, Gainesville, FL, 32611, United States
2 - University Of Florida, FLORIDA MUSEUM OF NAT. HISTORY, 1659 Museum Rd., 354 Dickinson Hall, Gainesville, FL, 32611, United States
3 - The New York Botanical Garden, Institute Of Systematic Botany, 2900 Southern Blvd., Bronx, NY, 10458, United States
4 - University Of Florida, Department Of Biology, 220 Bartram Hall, PO Box 118525, Gainesville, FL, 32611, United States
5 - Instituto de Biociências, Departamento de Botânica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, 90650-001, Brazil
6 - Florida Museum Of Natural History, Department Of Natural History, 1659 Museum Rd. , Gainesville, FL, 32611, United States

Keywords:
Comparative Phylogenetics
Neotropics
Paleotropics
radiation.

Presentation Type: Oral Paper
Session: PHYLOIII, Phylogenomics III
Location: Virtual/Virtual
Date: Thursday, July 22nd, 2021
Time: 10:30 AM(EDT)
Number: PHYLOIII003
Abstract ID:559
Candidate for Awards:None