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1.
Proc Natl Acad Sci U S A ; 114(40): 10695-10700, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28923966

RESUMO

Recent debates on the number of plant species in the vast lowland rain forests of the Amazon have been based largely on model estimates, neglecting published checklists based on verified voucher data. Here we collate taxonomically verified checklists to present a list of seed plant species from lowland Amazon rain forests. Our list comprises 14,003 species, of which 6,727 are trees. These figures are similar to estimates derived from nonparametric ecological models, but they contrast strongly with predictions of much higher tree diversity derived from parametric models. Based on the known proportion of tree species in neotropical lowland rain forest communities as measured in complete plot censuses, and on overall estimates of seed plant diversity in Brazil and in the neotropics in general, it is more likely that tree diversity in the Amazon is closer to the lower estimates derived from nonparametric models. Much remains unknown about Amazonian plant diversity, but this taxonomically verified dataset provides a valid starting point for macroecological and evolutionary studies aimed at understanding the origin, evolution, and ecology of the exceptional biodiversity of Amazonian forests.


Assuntos
Biodiversidade , Bases de Dados Factuais , Plantas/classificação , Floresta Úmida , Brasil
2.
Mol Phylogenet Evol ; 137: 44-63, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30999036

RESUMO

With 145 species, Turnera is the largest genus of Turneraceae (Malpighiales). Despite several morphotaxonomic and cytogenetic studies, our knowledge about the phylogenetic relationships in Turnera remains mainly based on morphological data. Here, we reconstruct the most comprehensive phylogeny of Turnera with molecular data to understand the morphological evolution within this group and to assess its circumscription and infrageneric classification. We analyzed two nuclear and six plastid markers and 112 taxa, including species and infraspecific taxa, 97 from Turnera, covering the 11 series of the genus. Bayesian inference, maximum parsimony and maximum likelihood analyses show that Turnera, as traditionally circumscribed, is not monophyletic. The genus is divided into two well-supported independent clades; one of them is sister to the genus Piriqueta and is here segregated as the new genus Oxossia. According to our reconstructions, Turnera probably evolved from an ancestor without extrafloral nectaries and with solitary, homostylous flowers with yellow petals. The emergences of extrafloral nectaries and distyly, both common in extant taxa, played an important role in the diversification of the genus. An updated infrageneric classification reflecting the relationships within Turnera is now possible based on morphological synapomorphies and is here designed for further studies.


Assuntos
Classificação , Filogenia , Turnera/anatomia & histologia , Turnera/genética , Teorema de Bayes , Biodiversidade , Sequência Consenso , Inflorescência/genética , Tricomas/genética , Turnera/classificação
3.
Am J Bot ; 102(6): 992-1007, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26101423

RESUMO

PREMISE OF THE STUDY: The Tetramerium lineage (Acanthaceae) presents a striking ecological structuring in South America, with groups concentrated in moist forests or in seasonally dry forests. In this study, we investigate the circumscription and relationships of the South American genera as a basis for better understanding historic interactions between dry and moist biomes in the Neotropics. METHODS: We dated the ancestral distribution of the Tetramerium lineage based on one nuclear and four plastid DNA regions. Maximum parsimony, maximum likelihood, and Bayesian inference analyses were performed for this study using 104 terminals. Phylogenetic divergences were dated using a relaxed molecular clock approach and ancestral distributions obtained from dispersal-vicariance analyses. KEY RESULTS: The genera Pachystachys, Schaueria, and Thyrsacanthus are nonmonophyletic. A dry forest lineage dispersed from North America to South America and reached the southwestern part of the continent between the end of the Miocene and beginning of the Pleistocene. This period coincides with the segregation between Amazonian and Atlantic moist forests that established the geographic structure currently found in the group. CONCLUSIONS: The South American genera Pachystachys, Schaueria, and Thyrsacanthus need to be recircumscribed. The congruence among biogeographical events found for the Tetramerium lineage suggests that the dry forest centers currently dispersed throughout South America are relatively old remnants, probably isolated since the Neogene, much earlier than the Last Glacial Maximum postulated by the Pleistocene Arc hypothesis. In addition to exploring the Pleistocene Arc hypothesis, this research also informs evolution in a lineage with numerous geographically restricted and threatened species.


Assuntos
Acanthaceae/classificação , Dessecação , Florestas , Modelos Biológicos , Filogenia , Estações do Ano , Teorema de Bayes , Intervalos de Confiança , América do Sul , Fatores de Tempo
4.
Ann Bot ; 114(5): 945-59, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25139428

RESUMO

BACKGROUND AND AIMS: Icacinaceae sensu stricto consist of a group of early branching lineages of lamiids whose relationships are not yet resolved and whose detailed floral morphology is poorly known. The most bizarre flowers occur in Emmotum: the gynoecium has three locules on one side and none on the other. It has been interpreted as consisting of three fertile and two sterile carpels or of one fertile carpel with two longitudinal septa and two sterile carpels. This study focused primarily on the outer and inner morphology of the gynoecium to resolve its disputed structure, and ovule structure was also studied. In addition, the perianth and androecium were investigated. METHODS: Flowers and floral buds of two Emmotum species, E. harleyi and E. nitens, were collected and fixed in the field, and then studied by scanning electron microscopy. Microtome section series were used to reconstruct their morphology. KEY RESULTS: The gynoecium in Emmotum was confirmed as pentamerous, consisting of three fertile and two sterile carpels. Each of the three locules behaves as the single locule in other Icacinaceae, with the placenta of the two ovules being identical, which shows that three fertile carpels are present. In addition, it was found that the ovules are bitegmic, which is almost unique in lamiids, and that the stamens have monosporangiate thecae, which also occurs in the closely related family Oncothecaceae, but is not known from any other Icacinaceae sensu lato so far. CONCLUSIONS: The flowers of Emmotum have unique characters at different evolutionary levels: the pseudotrimerous gynoecium at angiosperm level, the bitegmic ovules at lamiid level and the monosporangiate thecae at family or family group level. However, in general, the floral morphology of Emmotum fits well in Icacinaceae. More comparative research on flower structure is necessary in Icacinaceae and other early branching lineages of lamiids to better understand the initial evolution of this large lineage of asterids.


Assuntos
Evolução Biológica , Flores/anatomia & histologia , Magnoliopsida/anatomia & histologia , Flores/genética , Magnoliopsida/genética , Microscopia Eletrônica de Varredura , Óvulo Vegetal/anatomia & histologia , Óvulo Vegetal/genética , Filogenia
5.
BMC Ecol Evol ; 23(1): 13, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081378

RESUMO

Plants have demonstrated tremendous resilience through past mass extinction events. However, anthropogenic pressures are rapidly threatening plant survival. To develop our understanding of the impact of environmental change on plant ecology and evolution and help solve the current biodiversity crisis, BMC Ecology and Evolution has launched a new article Collection titled "Plants under Pressure".


Assuntos
Biodiversidade , Ecologia , Plantas , Extinção Biológica
6.
Mol Phylogenet Evol ; 65(3): 915-25, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22982434

RESUMO

Metastelmatinae is a neotropical subtribe of Asclepiadoideae (Apocynaceae), comprising 13 genera and around 260 species whose phylogenetic relationships are often unresolved or incongruent between plastid and nuclear datasets. The genus Minaria is one of the first lineages to emerge in the Metastelmatinae and is highly supported based on plastid markers. It comprises 21 species, most of which are endemic to small areas with open vegetation in the Espinhaço Range, Brazil. In the work presented here, we use plastid (rps16, trnH-psbA, trnS-trnG, and trnD-trnT) and nuclear (ITS and ETS) datasets to investigate the relationships within Minaria. We show that the three methods mostly used in phylogenetic studies, namely, maximum parsimony, maximum likelihood, and Bayesian Inference, have different performances and that a pluralistic analytical approach combining results from them can increase tree resolution and clade confidence, providing valuable phylogenetic information.


Assuntos
Apocynaceae/classificação , Evolução Molecular , Filogenia , Apocynaceae/genética , Teorema de Bayes , Brasil , Núcleo Celular/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Funções Verossimilhança , Análise de Sequência de DNA
7.
Biodivers Data J ; 8: e59664, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424242

RESUMO

BACKGROUND: Brazilian protected areas are essential for plant conservation in the Atlantic Forest domain, one of the 36 global biodiversity hotspots. A major challenge for improving conservation actions is to know the plant richness, protected by these areas. Online databases offer an accessible way to build plant species lists and to provide relevant information about biodiversity. A list of land plants of "Parque Nacional do Caparaó" (PNC) was previously built using online databases and published on the website "Catálogo de Plantas das Unidades de Conservação do Brasil." Here, we provide and discuss additional information about plant species richness, endemism and conservation in the PNC that could not be included in the List. We documented 1,791 species of land plants as occurring in PNC, of which 63 are cited as threatened (CR, EN or VU) by the Brazilian National Red List, seven as data deficient (DD) and five as priorities for conservation. Fifity-one species were possible new ocurrences for ES and MG states. NEW INFORMATION: "Parque Nacional do Caparaó" houses 8% of the land plant species endemic to the Brazilian Atlantic Forest, including 6% of its angiosperms, 31% of its lycophytes and ferns and 14% of its avascular plants. Twelve percent of the threatened species listed for the State of Espírito Santo and 7% listed for the State of Minas Gerais are also protected by PNC. Surprisingly, 79% of the collections analysed here were carried out in Minas Gerais, which represents just 21% of the total extension of the Park. The compiled data uncover a huge botanical collection gap in this federally-protected area.

8.
Biodivers Data J ; 8: e50837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508509

RESUMO

BACKGROUND: Brazil is one of the most biodiverse countries in the world, with about 37,000 species of land plants. Part of this biodiversity is within protected areas. The development of online databases in the last years greatly improved the available biodiversity data. However, the existing databases do not provide information about the protected areas in which individual plant species occur. The lack of such information is a crucial gap for conservation actions. This study aimed to show how the information captured from online databases, cleaned by a protocol and verified by taxonomists allowed us to obtain a comprehensive list of the vascular plant species from the "Parque Nacional do Itatiaia", the first national park founded in Brazil. All existing records in the online database JABOT (15,100 vouchers) were downloaded, resulting in 11,783 vouchers identified at the species level. Overall, we documented 2,316 species belonging to 176 families and 837 genera of vascular plants in the "Parque Nacional do Itatiaia". Considering the whole vascular flora, 2,238 species are native and 78 are non-native. NEW INFORMATION: The "Parque Nacional do Itatiaia" houses 13% of the angiosperm and 37% of the fern species known from the Brazilian Atlantic Forest. Amongst these species, 82 have been cited as threatened, following IUCN categories (CR, EN or VU), seven are data deficient (DD) and 15 have been classified as a conservation priority, because they are only known from a single specimen collected before 1969.

9.
PeerJ ; 7: e7333, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31367486

RESUMO

In a world where changes in land cover and climate happen faster than ever due to the expansion of human activities, narrowly distributed species are predicted to be the first to go extinct. Studies projecting species extinction in tropical regions consider either habitat loss or climate change as drivers of biodiversity loss but rarely evaluate them together. Here, the contribution of these two factors to the extinction risk of narrowly distributed species (with ranges smaller than 10,000 km2) of seed plants endemic to a fifth-order watershed in Brazil (microendemics) is assessed. We estimated the Regional Climate Change Index (RCCI) of these watersheds (areas with microendemics) and projected three scenarios of land use up to the year 2100 based on the average annual rates of habitat loss in these watersheds from 2000 to 2014. These scenarios correspond to immediate conservation action (scenario 1), long-term conservation action (scenario 2), and no conservation action (scenario 3). In each scenario, areas with microendemics were classified into four classes: (1) areas with low risk, (2) areas threatened by habitat loss, (3) areas threatened by climate change, and (4) areas threatened by climate change and habitat loss. We found 2,354 microendemic species of seed plants in 776 areas that altogether cover 17.5% of Brazil. Almost 70% (1,597) of these species are projected to be under high extinction risk by the end of the century due to habitat loss, climate change, or both, assuming that these areas will not lose habitat in the future due to land use. However, if habitat loss in these areas continues at the prevailing annual rates, the number of threatened species is projected to increase to more than 85% (2,054). The importance of climate change and habitat loss as drivers of species extinction varies across phytogeographic domains, and this variation requires the adoption of retrospective and prospective conservation strategies that are context specific. We suggest that tropical countries, such as Brazil, should integrate biodiversity conservation and climate change policies (both mitigation and adaptation) to achieve win-win social and environmental gains while halting species extinction.

10.
PhytoKeys ; (44): 1-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25698891

RESUMO

The taxonomic treatment of Begoniaceae for the state of Bahia, Brazil, led to the recognition of three new species of Begonia with narrow distributions, which are described and illustrated here: Begoniadelicata Gregório & J.A.S. Costa, sp. nov. is a herb restricted to the region of the Recôncavo; Begoniaelianeae Gregório & J.A.S. Costa, sp. nov. is a shrub endemic to the Atlantic forest of the southern part of the state; and Begoniapaganuccii Gregório & J.A.S. Costa, sp. nov. is a subshrub known only from the type material, collected in the Piedmont of Paraguaçu. Notes on morphology, comparisons with morphologically similar species, etymology, geographic distribution, habitat and phenological data for each species are also presented. Furthermore, keys are provided as an aid to separating the new species from congeneric species that occur in their surroundings. Due to the sparse knowledge of the new species, there is as yet insufficient data to accurately assess their conservation status.


ResumoO tratamento taxonômico das Begoniaceae do estado da Bahia, Brasil, resultou no reconhecimento de três espécies novas de Begonia com distribuição restrita, as quais são descritas e ilustradas aqui: Begoniadelicata Gregório & J.A.S. Costa, sp. nov. é uma erva restrita ao Recôncavo; Begoniaelianeae Gregório & J.A.S. Costa, sp. nov. é um arbusto endêmico da Mata Atlântica do sul do estado; e Begoniapaganuccii Gregório & J.A.S. Costa, sp. nov. é um subarbusto, conhecido apenas pelo espécime-tipo, coletado no Piemonte do Paraguaçu. São apresentados comentários morfológicos, comparações com espécies semelhantes, etimologia, distribuição geográfica, hábitat e dados fenológicos para cada espécie. Além disso, são fornecidas chaves de identificação para separá-las de espécies congenéricas que ocorrem na circunvizinhança dessas espécies. Devido ao conhecimento esparso das novas espécies, os dados ainda são insuficientes para classificá-las acuradamente quanto ao estado de conservação.

11.
Toxicon ; 58(6-7): 610-3, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21930141

RESUMO

Neurological signs were observed in cattle consuming the roots of Marsdenia hilariana and sheep consuming leaves of Marsdenia megalantha. Similar nervous signs to those observed in spontaneous poisoning were induced experimentally by the administration of roots of M. hilariana to goats, and by the administration of leaves and roots of M. megalantha to sheep. No lesions were observed at necropsies and on histological examination of the nervous system and other tissues.


Assuntos
Doenças dos Bovinos/etiologia , Doenças das Cabras/etiologia , Marsdenia/intoxicação , Intoxicação por Plantas/veterinária , Doenças dos Ovinos/etiologia , Animais , Brasil , Bovinos , Cabras , Ovinos
12.
Biota neotrop. (Online, Ed. port.) ; 13(3): 345-349, 2013. graf
Artigo em Português | LILACS | ID: lil-694008

RESUMO

Foi elaborada uma chave interativa para a identificação das 26 espécies da Aliança Tabebuia (Bignoniaceae) nativas do estado da Bahia, Brasil. A partir de uma página web, contendo caixas de seleção com caracteres botânicos, de marcação livre e não sequencial, vão se eliminando as espécies que não atendem aos critérios selecionados até a identificação completa do material. A chave está inserida em um site, contendo informações sobre Bignoniaceae, a Aliança Tabebuia e o estado da Bahia, bem como um glossário dos termos botânicos utilizados na chave e um banco de imagens. O sistema foi desenvolvido a partir das linguagens HTML e Javascript, é autoexecutável em CD-ROM e está disponível para download em: http://www.mendeley.com/profiles/alessandro-rapini/publications/ComputerProgram/. A utilização das chaves interativas facilita e dinamiza o processo de identificação dos táxons, contribuindo para a difusão do conhecimento biológico e elaboração de programas voltados ao reconhecimento e conservação da biota.


An interactive key to identify the 26 species of the Tabebuia Alliance (Bignoniaceae) from the state of Bahia, Brazil, was developed. From a web page containing check boxes with botanical characters, with free and not sequential marking, species which not match to the criteria are eliminated until the complete identification of the material. The key is hosted in a website, that also provides general information about the Bignoniaceae, the Tabebuia Alliance and the state of Bahia, as well as a glossary of the botanical terminology employed in the key and a bank of images. The system was created using HTML and Javascript languages. It runs from a CD-ROM and is available for download at: http://www.mendeley.com/profiles/alessandro-rapini/publications/ComputerProgram/. The use of interactive keys facilitates and streamlines the process of taxa identification, contributing to the dissemination of biological knowledge and preparation of programs to the recognition and conservation of biota.

13.
Neotrop Entomol ; 37(3): 338-41, 2008.
Artigo em Português | MEDLINE | ID: mdl-18641907

RESUMO

The presence of pollinaria of two species of Asclepiadoideae (Apocynaceae), possibly Tassadia cf. martiana Decne. and T. cf. obovata Decne., attached to the mouth parts of simulid black flies [Cerqueirellum amazonicum (Goeldi), C. argentiscutum (Shelley & Luna Dias), C. oyapockense (Floch & Abonnenc), and Cerqueirellum sp.] are reported for the first time. The frequency and distribution of simulids recorded with pollinaria suggest that removal of pollinaria by these flies is not casual. Simulids probably use nectar in flowers of Asclepiadoideae as source of sugar, being able to remove their pollinaria. This finding demonstrates that simulids are not only vector of pathogenic parasites, but also carry pollinaria, and thus may represent a group of pollinators for species of Asclepiadoideae with small flowers.


Assuntos
Apocynaceae/anatomia & histologia , Polinização/fisiologia , Simuliidae , Animais , Apocynaceae/fisiologia , Feminino , Flores/anatomia & histologia , Simuliidae/anatomia & histologia
14.
Neotrop. entomol ; 37(3): 338-341, May-June 2008. ilus, tab
Artigo em Português | LILACS | ID: lil-486572

RESUMO

Polinários de duas espécies de Asclepiadoideae (Apocynaceae), possivelmente de Tassadia cf. martiana Decne. e T. cf. obovata Decne., foram observados pela primeira vez presos ao aparelho bucal de simulídeos [Cerqueirellum amazonicum (Goeldi), C. argentiscutum (Shelley & Luna Dias), C. oyapockense (Floch & Abonnenc) e Cerqueirellum sp.]. A frequência e distribuição dos insetos observados com polinários sugerem que esse tipo de evento não é casual. Os simulídeos devem buscar néctar nas flores de Asclepiadoideae, sendo capazes de remover seus polinários. Essa descoberta demonstra que os simulídeos não carregam apenas parasitas patogênicos, mas também polinários, e assim podem representar um grupo de polinizadores de espécies de Asclepiadoideae com flores pequenas.


The presence of pollinaria of two species of Asclepiadoideae (Apocynaceae), possibly Tassadia cf. martiana Decne. and T. cf. obovata Decne., attached to the mouth parts of simulid black flies [Cerqueirellum amazonicum (Goeldi), C. argentiscutum (Shelley & Luna Dias), C. oyapockense (Floch & Abonnenc), and Cerqueirellum sp.] are reported for the first time. The frequency and distribution of simulids recorded with pollinaria suggest that removal of pollinaria by these flies is not casual. Simulids probably use nectar in flowers of Asclepiadoideae as source of sugar, being able to remove their pollinaria. This finding demonstrates that simulids are not only vector of pathogenic parasites, but also carry pollinaria, and thus may represent a group of pollinators for species of Asclepiadoideae with small flowers.


Assuntos
Apocynaceae , Pólen , Simuliidae
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