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• Our results highlight the importance of the number of locules in Myrcia classification. • The widespread and taxonomically complex Myrcia guianensis is non-monophyletic. • Myrcia sect. Aguava appears to have originated in the Cerrado. • Transitions from Cerrado to humid forests occurred in the evolution of M. sect. Aguava. • Combination of NGS and Sanger data is possible and generates robust phylogenetic trees. 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. [ABSTRACT FROM AUTHOR]

Oxalis sect. Holophyllum (Oxalidaceae) is a small group of species that is endemic to the Brazilian Atlantic Forest in the states of Rio de Janeiro, Minas Gerais, Espírito Santo, and Bahia. Species of the section can be recognized by their unifoliolate leaves, one-seeded carpels, and the common presence of dorsiventrally flattened (and sometimes winged) peduncles and/or petioles. Circumscriptions of the currently accepted species needed to be revaluated, as the overlap in several features have blurred limits among morphologically similar taxa. In this study we evaluate the monophyly and phylogenetic relationships among species of O. sect. Holophyllum, and provide an updated taxonomic study of the section, aiming at improving species circumscriptions and facilitating species-level identification. For this task, we analyzed samples from herbaria and carried out fieldwork to observe the plants in loco, collect samples, and gather material for DNA extraction, amplification, and sequencing. Bayesian and maximum likelihood phylogenetic analyses were performed using sequences from three markers: nrITS, and plastid trnL-trnF, and petA-psbJ from 13 of the 17 currently accepted species, which corroborate the monophyly of the section. Among the species of O. sect. Holophyllum, ten are newly described here at species level: O. adpressipila Fiaschi & Bilk (based on O. kuhlmannii Lourteig var. adpressipila Lourteig), O. capixaba Fiaschi & Bilk, O. cornicarpa Fiaschi, O. inopinata Fiaschi & Bilk, O. itamarajuensis Fiaschi & Bilk (based on O. alata Mart. ex Zucc. var. hirta Lourteig), O. leonii Fiaschi & Bilk, O. occulta Fiaschi & Bilk, O. retrorsa Fiaschi & Bilk, O. sciophila Fiaschi & Bilk, and O. septentrionalis Fiaschi & Bilk. Lectotypes are chosen for nine names, and an epitype for O. impatiens Vell. An identification key to all species is provided, as well as descriptions, illustrations, geographic distribution maps, and preliminary conservation statuses following IUCN guidelines. Oxalis sect. Holophyllum (Oxalidaceae) é um pequeno grupo de espécies endêmicas à Mata Atlântica dos estados do Rio de Janeiro, Minas Gerais, Espírito Santo e Bahia. Espécies da seção podem ser reconhecidas pelas folhas unifolioladas, carpelos unisseminados, e geralmente pela presença de pedúnculos e/ou pedicelos achatados dorsiventralmente ou, às vezes, alados. As circunscrições das espécies atualmente aceitas precisam ser reavaliadas, já que a sobreposição observada em vários caracteres mascara limites entre táxons morfologicamente similares. Neste estudo nós investigamos o monofiletismo e as relações filogenéticas entre espécies de O. sect. Holophyllum e fornecemos uma atualização taxonômica da seção, com o intuito de aprimorar as circunscrições das espécies e facilitar a sua identificação. Para atingir esses objetivos, nós analisamos amostras de herbários e conduzimos expedições a campo para observar as plantas in loco, coletar amostras e recolher materiais para a extração, amplificação e sequenciamento de DNA. Análises filogenéticas bayesianas e de máxima verossimilhança foram conduzidas a partir de sequências do ITS (nuclear) e do trnL-trnF e petA-psbJ (plastidiais) de 13 das 17 espécies atualmente aceitas, o que corroborou o monofiletismo da seção. Entre as espécies de O. sect. Holophyllum, dez são pela primeira vez descritas em nível específico: O. adpressipila Fiaschi & Bilk (baseada em O. kuhlmannii Lourteig var. adpressipila Lourteig), O. capixaba Fiaschi & Bilk, O. cornicarpa Fiaschi, O. inopinata Fiaschi & Bilk, O. itamarajuensis Fiaschi & Bilk (baseada em O. alata Mart. ex Zucc. var. hirta Lourteig), O. leonii Fiaschi & Bilk, O. occulta Fiaschi & Bilk, O. retrorsa Fiaschi & Bilk, O. sciophila Fiaschi & Bilk e O. septentrionalis Fiaschi & Bilk. Lectótipos são escolhidos para nove nomes e um epítipo para O. impatiens Vell. Uma chave de identificação para todas as espécies é fornecida, bem como descrições, ilustrações, mapas de distribuição geográfica e análises preliminares do status de conservação segundo as normas da IUCN. [ABSTRACT FROM AUTHOR]

[Display omitted] • A large portion of Miconia from the Atlantic Forest were assigned to a new section and supersection. • Glomerulate inflorescences in Miconia were derived from scorpioid ones. • Indument on young branches and leaves are useful for supersection and sections circumscriptions. • Miconia biogeography suggests independent dispersals to Atlantic Forest. 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 (atp F-H, psb K-I, and psa I- acc D) 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. [ABSTRACT FROM AUTHOR]