Guilherme M. Antar

Angiosperms are the cornerstone of most terrestrial ecosystems and human livelihoods,. A robust understanding of angiosperm evolution is required to explain their rise to ecological dominance. So far, the angiosperm tree of life has been determined primarily by means of analyses of the plastid genome,. Many studies have drawn on this foundational work, such as classification and first insights into angiosperm diversification since their Mesozoic origins, –. However, the limited and biased sampling of both taxa and genomes undermines confidence in the tree and its implications. Here, we build the tree of life for almost 8,000 (about 60%) angiosperm genera using a standardized set of 353 nuclear genes. This 15-fold increase in genus-level sampling relative to comparable nuclear studies provides a critical test of earlier results and brings notable change to key groups, especially in rosids, while substantiating …

The hexane extract from twigs of Piper truncatum Vell (Piperaceae) displayed activity against Trypanosoma cruzi and was subjected to chromatographic steps to afford six dibenzylbutyrolactolic lignans, being four knowns: cubebin (1), (‐)‐9α‐O‐methylcubebin (2), (+)‐9β‐O‐methylcubebinin (3) and 3,4‐dimethoxy‐3,4‐demethylenedioxycubebin (4) as well as two new, named truncatin A (5) and B (6). Initially, in vitro activity against trypomastigotes was evaluated and compounds 1, 4 and 6 exhibited EC50 values of 41.6, 21.0 and 39.6 μM, respectively. However, when tested against amastigotes, the relevant clinical form in the chronic phase of Chagas disease, compounds 1 – 6 displayed activities with EC50 values ranging from 1.6 to 13.7 μM. In addition, the mammalian cytotoxicity of compounds 1 – 6 was evaluated against murine fibroblasts (NCTC). Compounds 2, 3 and 4 exhibited reduced toxicity against …

Piriqueta velutina is described as a new species, illustrated, geographically mapped and its diagnostic characteristics and taxonomic affinities are described. The new species can be recognised mainly by the presence of serial branches (branches from serial buds predominantly in the apical portion of the plant), the short internodes and oblique or erect leaves which partially overlap in dried specimens; the ovate to elliptic leaf blade with a golden brown velutinous indumentum, and the conical or bulbous bases of the glandular setiform trichomes, frequently darkened on young leaf margins and on the abaxial surface. Its conservation status is preliminarily assessed as Endangered, it occurs in Brazilian Cerrado (savanna vegetation), in the Jalapão region, state of Tocantins, North region of Brazil.

Salvia sect. Angulatae and S. sect. Nobiles are among the sections of Salvia L. (Lamiaceae) with most of their Brazilian species represented in the Atlantic Forest and the Cerrado domains, which are important regions of species richness for the genus. After extensive evaluation of the literature, populations in situ and specimens in herbaria, including nomenclatural types, we identified a requirement for taxonomic and nomenclatural changes in S. arenaria and S. sellowiana, and for updated identification keys and taxonomic notes for the other members of these sections, particularly S. rivularis in S. sect. Nobiles. Two names are synonymised, Salvia articulata = S. sellowiana and S. itatiaiensis = S. arenaria and notes on the nomenclature and morphology of these species are provided. A first-step lectotypification (S. arenaria var. sellowii) and a second-step lectotypification (S. itatiaiensis) are also presented, as well as …

Endemic in 21 countries, Chagas disease, also known as American Trypanosomiasis, is a neglected tropical disease (NTD) caused by the protozoan parasite Trypanosoma cruzi. The available drugs for the treatment of this disease, benznidazole and nifurtimox, are outdated and display severe side effects. Thus, the discovery of new drugs is crucial. Based on our continuous studies aiming towards the discovery of natural products with anti-T. cruzi potential, the MeOH extract from aerial parts of Baccharis sphenophylla Dusén ex. Malme (Asteraceae) displayed activity against this parasite and was subjected to high-performance countercurrent chromatography (HPCCC), to obtain one unreported syn-labdane diterpene — sphenophyllol (1) — as well as the known compounds gaudichaudol C (2), ent-kaurenoic acid (3), hispidulin (4), eupafolin (5), and one mixture of di-O-caffeoylquinic acids (6–8). Compounds 1–8 were characterized by analysis of nuclear magnetic resonance (NMR) and mass spectrometry (MS) data. When tested against trypomastigote forms, isolated labdane diterpenes 1 and 2 displayed potent activity, with EC50 values of 20.1 μM and 2.9 μM, respectively. The mixture of chlorogenic acids 6–8, as well as the isolated flavones 4 and 5, showed significant activity against the clinically relevant amastigotes, with EC50 values of 24.9, 12.8, and 2.7 μM, respectively. Nonetheless, tested compounds 1–8 displayed no cytotoxicity against mammalian cells (CC50 > 200 μM). These results demonstrate the application of HPCCC as an important tool to isolate bioactive compounds from natural sources, including the antitrypanosomal …

Calyceraceae apresenta ervas ou subarbustos de com talos radicantes. Suas folhas são simples, alternas e/ou em rosetas basais, ovais, lineares ou lanceoladas, limbo inteiro, lobado e geralmente dentado, não apresentam estípula. Inflorescências em capítulo involucrados centrípetos, sendo sésseis ou pedunculadas, as flores são raramente zigomorfas,(4)-5-(6)-meras, gamopétalas e gamossépalas, infundibuliforme, alva a amarelada. Fruto diclesio, cálice persistente, às vezes espinescente na maturação, coalescente ou não aos adjacentes. A família possui oito gêneros e 46 espécies endêmicas do sul da América do Sul. No Brasil são registrados dois gêneros e seis espécies (sendo duas endêmicas), das quais, segundo levantamento preliminar, apenas uma ocorre no estado do Espírito Santo. O projeto Flora do Espírito Santo objetiva realizar o tratamento taxonômico para todos os táxons de plantas e …

Lamiaceae apresenta 236 gêneros e cerca de 7.200 espécies com distribuição cosmopolita, principalmente em regiões tropicais. No Brasil são registrados 50 gêneros e 527 espécies nativas, das quais 358 são consideradas endêmicas. Apesar de considerável riqueza no Espírito Santo, com 45 espécies nativas listadas, nenhum estudo florístico recente foi realizado com a família no estado. A Reserva Biológica do Córrego do Veado, localizada no município de Pinheiros, é um dos poucos remanescentes florestais conservados do Norte do ES, sendo sua flora ainda pouco explorada. Esse estudo teve como objetivo apresentar um levantamento florístico de Lamiaceae para a Reserva Biológica Córrego do Veado. Coletas de campo foram realizadas na reserva desde 2019, compreendendo diversos períodos do ano, com a coleta de material fértil, o qual, após processamento, foi depositado no herbário SAMES …

A new species of Lamiaceae, Marsypianthes dunensis, from the restingas of the Brazilian Atlantic Forest is described and illustrated. The new species is compared to M. foliolosa and M. chamaedrys, the most polymorphic and widely distributed species of the genus. A geographic distribution map is provided, plus a preliminary conservation assessment and a key for the identification of all Marsypianthes species.

Hyptis albolanata is here described and illustrated. This new species is morphologically similar to Hyptis tetragona due to having ovate to elliptic leaves and a pedunculate capitula, differing mainly in the indumentum, leaf base, and calyx morphology. We provide a full description, a line drawing, and photographs of Hyptis albolanata, as well as a distribution map, a preliminary conservation status assessment, comments on the species ecology and comparison with morphologically similar taxa.

Amazonia, despite being famous as the most prominent tropical forest, is currently suffering high rates of degradation, with recurrent fires and deforestation, which could shortly lead it to be classified as a biodiversity hotspot for conservation. Although the known flora of the domain displays exceptional richness, its diversity is far from being well known, with several new species being described each year and lots of areas still poorly collected. During the preparation of a revision of Hyptidendron (Lamiaceae, subtribe Hyptidinae), a small genus with 21 species, unidentified and unmatched specimens from the Amazonian domain were uncovered. Here we describe and illustrate these specimens as Hyptidendron dorothyanum sp. nov., named in honor of Sister Dorothy Stang, murdered for her support for the biodiversity of the Amazon and her defence of the rights of local people. The new species, currently known from …

Menthinae, one of the five subtribes of Mentheae (Lamiaceae), with ca. 735 species, is represented in Brazil by a wide range of herbs and shrubs. During an investigation of the taxonomic history of the group for the Flora e Funga do Brasil project, several nomenclatural issues with typifications in the group have been identified. This study attempts to resolve them, making suggestions of new types and re-evaluation of synonyms. Thirteen lectotypifications and one neotypification are being proposed, along with the recognition of Thymus selloi Spreng. ex J.A.Schmidt as a nomen nudum. Most of the suggested changes are due to the loss of many of Sellow’s types at B during WWII, lack of specific herbaria references and collector numbers in the protologues, or to existence of designated syntypes in the referred collections. Our study is a contribution to the nomenclatural and taxonomic knowledge of Menthinae …

Chemical investigation of ethyl acetate and n-butanol fractions from methanol extracts from leaves of Hydrocotyle leucocephala Cham. & Schltdl. and aerial parts of H. bonariensis Comm. ex Lam. resulted in the identification of 6 compounds and a putative identification of 12 more, including thirteen glycosylated flavonols (1–13), two dibenzylbutyrolactone lignans (14 and 15) and three diacetylenes (16–18) based on UPLC-ESI-QToF-MS/MS analysis in the positive and negative ionization modes. In the case of compounds 3, 14–18, their structures were confirmed by analysis of NMR spectra. Compounds 5, 7, 10–12 or isomeric compounds of them were identified for the first time in this genus. The obtained results contribute with chemotaxonomy of Hydrocotyle since flavonoids, dibenzylbutyrolactone lignans, and diacetylenes were characterized, in consonance with other species previously investigated.

As the adverse impacts of hydrological extremes increase in many regions of the world, a better understanding of the drivers of changes in risk and impacts is essential for effective flood and drought risk management and climate adaptation. However, there is currently a lack of comprehensive, empirical data about...

As the adverse impacts of hydrological extremes increase in many regions of the world, a better understanding of the drivers of changes in risk and impacts is essential for effective flood and drought risk management and climate adaptation. However, there is currently a lack of comprehensive, empirical data about...

Book Contribution | Rhamnaceae. | ID: eae2b43c-bded-41cc-b5de-ddf96d2dddf8 | Hyku Skip to Content Shared Research Repository Home About Help Contact Switch language English Switch language Deutsch English Español Français Italiano Português do Brasil 中文 Login Home About Help Contact Research Repository 1.Home Book chapter Rhamnaceae. Public Deposited Creator Cahan, Daniel ( ORCID ) 2023 You do not have access to any existing collections. You may create a new collection. Close There are no publicly available items in this Book Contribution. Metadata Resource Type Book chapter Creator Cahan, Daniel ( ORCID ) Date published 2023-04 Institution Royal Botanic Gardens, Kew Organisational unit Science Project name Priority 4: Accelerated Taxonomy Book title The Kew Temperate Plant Families Identification Handbook. Editor Bramley, Gemma ( ORCID ISNI ) Trias-Blasi, Anna ( …

As the adverse impacts of hydrological extremes increase in many regions of the world, a better understanding of the drivers of changes in risk and impacts is essential for effective flood and drought risk management and climate adaptation. However, there is currently a lack of comprehensive, empirical data about...

The subtribe Hyptidinae (Lamiaceae) is predominantly Neotropical with ca. 400 species, most diverse in the Cerrado domain, the Brazilian savanna. Mato Grosso state, located in the core of the Cerrado, owns a remarkable richness in the subtribe with 71 species recognized. Robert Pilger, who accompanied Hermann Meyer on an expedition to the state in 1898, collected about 700 angiosperm specimens that were mostly deposited in the Berlin Herbarium and many subsequently destroyed during the 2nd World War, with few if any duplicates surviving. Five species of Hyptidinae were described by Pilger based on these materials from Mato Grosso, subsequently were lectotypified by Epling, and later destroyed. They are: Hyptis helophila Pilg. (= H. petiolaris Pohl ex Benth.), H. indivisa Pilg. (= Cantinoa indivisa (Pilg.) Harley & J.F.B.Pastore), H. lasiocalyx Pilg. (= Cyanocephalus desertorum (Pilg.) Harley & J.F.B …

O estudo de Caricaceae integra o projeto “Flora da Serra do Cipó, Minas Gerais, Brasil''. A família está representada na área por apenas uma espécie: Jacaratia heptaphylla (Vell.) A. DC. São apresentadas uma descrição e uma ilustração da espécie, além de comentários sobre distribuição geográfica, variabilidade e aspectos ecológicos.

O estudo taxonômico de Hydroleaceae é aqui apresentado como parte do projeto “Flora da Serra do Cipó, Minas Gerais, Brasil”. A família está representada na área por uma espécie: Hydrolea spinosa L., para a qual apresentamos uma descrição, ilustração, além de comentários sobre a distribuição geográfica, habitat e fenologia.

The shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive …