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Miconia is among the largest plant genera in the Neotropics and a taxonomically complex lineage. Indeed, molecular phylogenetic data shows that none of its traditionally accepted sections are monophyletic, preventing taxonomic advances within the genus. Miconia is the largest plant genus in the Brazilian Atlantic Forest, including three main lineages, the Leandra s.s. clade (ca. 215 spp.), the Miconia sect. Chaenanthera (24 spp.), and the Miconia discolor clade (estimated 77 spp.). Out of these lineages, the Miconia discolor clade is the only currently lacking phylogenetic data, complicating its taxonomy. In this study, we reconstruct the phylogeny of the Miconia discolor clade, using three plastid (atpF-H, psbK-I, and psaI-accD) and two nuclear (ETS and ITS) markers. We sampled 60 out of the 77 species of the group, representing 78% of its diversity. Taxa were selected considering their distribution, morphology, and previous phylogenetic knowledge. We used the newly reconstructed phylogeny to better understand phylogenetic relationships among Atlantic Forest species and morphologically similar taxa, and to propose a new infrageneric classification for the Miconia discolor clade: the Miconia supersection Discolores. We further studied the evolution of seven morphological characters using a Maximum Likelihood approach, and estimated the ancestral range distribution of various lineages in order to understand the biogeographic history of this clade. We found that dichasial inflorescences represent the ancestral condition within Miconia, subsequently giving rise to scorpioid and glomerulate inflorescences in the studied group. We describe Miconia supersect. Discolores, originated in the Amazon region, which is recognized by a dense layer of branched tricomes covering young branches and non-dichasial inflorescences, including three main lineages: (i) Miconia sect. Albicantes, characterized by persistent bracts and arachnoid indument on the abaxial surface of leaves, mainly distributed in the Amazon basin; (ii) Miconia sect. Discolores, characterized by caducous calyx lobes and glomerulate inflorescences, centered in the Atlantic Forest; and (iii) Miconia sect. Multispicatae, characterized by leaves not completely covered with indument, and capitate stigma, mainly distributed in the Atlantic Forest. All three sections and the supersection originated in the Neogene, between the Late Miocene and the Early Pliocene., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Myrcia is one of the largest exclusively Neotropical angiosperm genera, including ca. 800 species divided into nine sections. Myrcia sect. Aguava is one of most complex sections of Myrcia due to high morphological variation and wide distribution range of some species, including M. guianensis, with distribution throughout South America and a complex taxonomic history. We used complete plastid DNA sequences data generated using next-generation sequencing of 45 terminals, mostly from Myrcia sect. Aguava. These data were combined with five target DNA regions (ITS, psbA-trnH, trnL-trnF, trnQ-rps16, ndhF) of additional terminals to increase taxonomic coverage. Phylogenetic analyses were conducted using a maximum likelihood approach, and divergence times and ancestral range distributions were estimated. Myrcia sect. Aguava is monophyletic and exclusively comprises species with trilocular ovaries but has no relationship with other groups within Myrcia that possess trilocular ovaries. Three main lineages that correspond to geographical distribution are recognized within Myrcia sect. Aguava. Multiple accessions reveal a non-monophyletic Myrcia guianensis and stress the biogeographical structure inside the group. Myrcia sect. Aguava had a probable mid-Miocene origin in the Cerrado, but lineages that persisted there diversified only more recently, when the present-day vegetation started to stabilize. Posterior migrations to Atlantic Forest, Amazon and Caribbean occurred at the end of Miocene, evidencing transitions from open and dry to forested and more humid areas that are less frequent in the Neotropics. Overall, it is observed that related lineages remained in ecologically similar environments. Future perspectives on Myrcia and Myrteae in the phylogenomic era are also discussed., (Crown Copyright © 2020. Published by Elsevier Inc. All rights reserved.)

Myrteae (c. 2500 species; 51 genera) is the largest tribe of Myrtaceae and an ecologically important groups of angiosperms in the Neotropics. Systematic relationships in Myrteae are complex, hindering conservation initiatives and jeopardizing evolutionary modelling. A well-supported and robust phylogenetic hypothesis was here targeted towards a comprehensive understanding of the relationships within the tribe. The resultant topology was used as a base for key evolutionary analyses such as age estimation, historical biogeography and diversification rate patterns. One nuclear (ITS) and seven chloroplast (psbA-trnH, matK, ndhF, trnl-trnF, trnQ-rps16, rpl16 and rpl32-trnL) DNA regions for 115 taxa representing 46 out of the 51 genera in the tribe were accessed and analysed using maximum likelihood and Bayesian inference tools for phylogenetic reconstruction. Dates of diversification events were estimated and contrasted using two distinct fossil sets (macro and pollen) in BEAST. The subsequent dated phylogenies were compared and analysed for biogeographical patterns using BioGeoBEARS and diversification rates using BAMM. Myrteae phylogeny presents strong statistical support for three major clades within the tribe: Australasian group, Myrtus group and Main Neotropical Lineage. Dating results from calibration using macrofossil are an average of 20 million years older and show an early Paleocene origin of Myrteae, against a mid-Eocene one from the pollen fossil calibration. Biogeographic analysis shows the origin of Myrteae in Zealandia in both calibration approaches, followed by a widespread distribution throughout the still-linked Gondwana continents and diversification of Neotropical endemic lineages by later vicariance. Best configuration shift indicates three points of acceleration in diversification rates, all of them occurring in the Main Neotropical Lineage. Based on the reconstructed topology, several new taxonomic placements were recovered, including: the relative position of Myrtus communis, the placement of the Blepharocalyx group, the absence of generic endemism in the Caribbean, and the paraphyletism of the former Pimenta group. Distinct calibration approaches affect biogeography interpretation, increasing the number of necessary long distance dispersal events in the topology with older nodes. It is hypothesised that biological intrinsic factors such as modifications of embryo type and polyploidy might have played a role in accelerating shifts of diversification rates in Neotropical lineages. Future perspectives include formal subtribal classification, standardization of fossil calibration approaches and better links between diversification shifts and trait evolution., (Copyright © 2017 Elsevier Inc. All rights reserved.)