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1.
PhytoKeys ; 227: 151-165, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37334177

RESUMEN

During surveys conducted on Neotropical Vanilla, a new endemic species was found in the Brazilian campos rupestres of the Espinhaço Range. Here, this new remarkable Vanilla species, namely V.rupicola Pansarin & E.L.F. Menezes, is described and illustrated. A phylogeny for Vanilla is presented and the relationships between Neotropical species are discussed. The position of V.rupicola among Neotropical Vanilla is discussed within an evolutionary context. Vanillarupicola is recognized by its rupicolous habit, its reptant stems, and its sessile and rounded leaves. This remarkable new taxon emerges in a clade that includes V.appendiculata Rolfe and V.hartii Rolfe. Vegetative and floral features support a close relationship between V.rupicola and sister taxa, mainly regarding the apical inflorescence (V.appendiculata), the type of appendages of the central crest of the labellum, and the labellar color pattern. Phylogenetic inference suggests that the circumscription of Neotropical Vanilla groups needs revision.

2.
Mol Ecol ; 32(12): 3165-3181, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36934376

RESUMEN

Mountains are renowned for their bountiful biodiversity. Explanations on the origin of such abundant life are usually regarded to their orogenic history. However, ancient mountain systems with geological stability also exhibit astounding levels of number of species and endemism, as illustrated by the Brazilian Quartzitic Mountains (BQM) in Eastern South America. Thus, cycles of climatic changes over the last couple million years are usually assumed to play an important role in the origin of mountainous biota. These climatic oscillations potentially isolated and reconnected adjacent populations, a phenomenon known as flickering connectivity, accelerating speciation events due to range fragmentation, dispersion, secondary contact, and hybridization. To evaluate the role of the climatic fluctuations on the diversification of the BQM biota, we estimated the ancient demography of distinct endemic species of animals and plants using hierarchical approximate Bayesian computation analysis and Ecological Niche Modelling. Additionally, we evaluated if climatic oscillations have driven a genetic spatial congruence in the genetic structure of codistributed species from the Espinhaço Range, one of the main BQM areas. Our results show that the majority of plant lineages underwent a synchronous expansion over the Last Glacial Maximum (LGM, c. 21 thousand years ago), although we could not obtain a clear demographic pattern for the animal lineages. We also obtained a signal of a congruent phylogeographic break between lineages endemic to the Espinhaço Range, suggesting how ancient climatic oscillations might have driven the evolutionary history of the Espinhaço's biota.


Asunto(s)
Variación Genética , Animales , Filogeografía , Filogenia , Teorema de Bayes , Brasil , Demografía
3.
Evolution ; 77(4): 946-958, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36688535

RESUMEN

Mountains play a crucial role in the origin and maintenance of Neotropical biodiversity, but there are still unanswered questions about the diversification of the campos rupestres (CR), an herbaceous-shrubby sky-island vegetation in eastern South America. For orchids distributed across this disjunct rock habitat, difficulties with distinguishing morphological taxa add an additional challenge to disentangling the history of divergence. Here, we combined the power of ddRAD genomic data with broad sampling of Bulbophyllum sect. Didactyle (Orchidaceae), across the CR and other Neotropical outcrops, to estimate evolutionary relationships and evaluate the biogeography of the group's diversification. Although genetic lineages generally align with geographic disjunctions, we also observe distantly related lineages within some previously recognized species. For such taxa, their lack of monophyly and a shared regional divergence pattern suggests a complex history that may include unrecognized diversity. When viewed through the lens of morphological variability, our study raises intriguing questions about the persistence and permeability of species barriers among orchid populations. These results, in addition to the recency of the divergence history of B. sect. Didactyle, provide insights about hypothesized community level vs. species-specific paths of diversification across the Neotropical sky-islands of the CR.


Asunto(s)
Evolución Biológica , Orchidaceae , Filogenia , Filogeografía , Brasil , Biodiversidad , Orchidaceae/genética , Orchidaceae/anatomía & histología
4.
Biota Neotrop. (Online, Ed. ingl.) ; 23(1): e20221384, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1429921

RESUMEN

Abstract Canga ecosystems are iron-rich habitats and pose a challenge for conservation and environmental governance in Brazil. They support high levels of biodiversity and endemism and, at the same time, have suffered intense losses and degradation due to large-scale iron ore mining. The Peixe Bravo River Valley in the Brazilian savanna is one of the last natural canga areas that has yet to face the irreversible impacts of mining. However, there are vast gaps in data on the vegetation cover, location, spatial distribution, and area of occurrence of this ecosystem. Therefore, more information is needed on the appropriate scale, without which it is difficult to establish conservation planning and strategies to prevent, mitigate or compensate for impacts on canga ecosystems. In this study, we provide the first map of canga ecosystems in Brazil using the U-Net deep learning model and Sentinel-2 images. In addition, we estimate the degree of direct threat faced by ecosystems due to the spatial overlap of the mapped cangas and the location of mining concession areas for iron ore exploitation. The deep learning algorithm identified and segmented 762 canga patches (overall accuracy of 98.5%) in an area of 30,000 ha in the Peixe Bravo River Valley, demonstrating the high predictive power of the mapping approach. We conclude that the direct threat to canga ecosystems is high since 99.6% of the observed canga patches are included in mining concession areas. We also highlight that the knowledge acquired about the distribution of cangas through the application of an effective method of artificial intelligence and the use of open-source satellite images is especially important for supporting conservation strategies and environmental public policies.


Resumo Os ecossistemas de Canga, habitats com elevadas concentrações de ferro, são um desafio para conservação e governança ambiental no Brasil. Eles sustentam uma alta biodiversidade e endemismo, e sofreram intensas perdas e degradações de áreas naturais devido à mineração de ferro em larga escala. O Vale do Rio Peixe Bravo, localizado no Cerrado brasileiro, é uma das últimas regiões com ecossistemas de canga que ainda não sofreu impactos irreversíveis da mineração. Mas ainda há ausência de dados sobre a cobertura vegetal, localização, distribuição geográfica e a área de ocorrência desse ecossistema. Portanto, a ausência de informações em escala adequada dificulta o planejamento em conservação e as estratégias para prevenir, mitigar ou compensar os impactos nos ecossistemas de canga. Neste estudo, nós fornecemos o primeiro mapa de ecossistemas de canga no Brasil elaborado a partir de deep learning segmentação U-Net e imagens de satélite Sentinel-2. Além disso, nós estimamos o grau de ameaça direta dos ecossistemas devido a sobreposição espacial das manchas de cangas preditas e a localização dos títulos de concessão minerária para exploração do minério de ferro. O algoritmo de aprendizado profundo identificou 762 manchas de canga (acurácia acima de 98,5%) em uma área de 30.000 ha no Vale do Rio Peixe Bravo, demonstrando o alto poder preditivo do método de mapeamento. Nós estimamos que há um alto grau de ameaça direta aos ecossistemas de canga, uma vez que 99,6% das manchas de cangas preditas estão incluídas em áreas de concessão de mineração. Nós também destacamos que o conhecimento adquirido sobre a distribuição das cangas por meio da aplicação de um método eficaz de inteligência artificial e do uso de imagens de satélite de código aberto é especialmente importante para apoiar estratégias de conservação e políticas públicas ambientais.

5.
Preprint en Inglés | SciELO Preprints | ID: pps-3717

RESUMEN

We present the taxonomic treatment for the Orobanchaceae family from Serra de São José and from Serra do Lenheiro, in Minas Gerais State, Brazil. Six species and four genera were recorded. Identification key, morphological descriptions, photos and comments on geographic distribution, ecology and taxonomy of the species are provided.


Nós apresentamos o tratamento taxonômico para a família Orobanchaceae da Serra de São José e da Serra do Lenheiro, no Estado de Minas Gerais, Brasil. Seis espécies e quatro gêneros foram registrados. Chave de identificação, descrições morfológicas, fotos e comentários sobre a distribuição geográfica, ecologia e taxonomia das espécies são apresentados.

6.
Ecol Evol ; 11(6): 2551-2560, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33815762

RESUMEN

Over 70% of the total channel length in all river basins is formed by low order streams, many of which originate on mountaintops. Headwater streams play fundamental roles in processing and transporting terrestrial and aquatic organic matter, often harboring high biodiversity in bottom leaf patches deposited from riparian vegetation. The objective of this study was to assess the variation in taxonomic composition (measured by beta diversity of aquatic macroinvertebrates) among stream sites located in the Espinhaço Meridional Mountain Range, part of a UNESCO Biosphere Reserve in eastern Brazil. We tested two hypotheses. (a) Taxa turnover is the main reason for differences in aquatic insect assemblages within stream sites; we predicted that turnover would be higher than nestedness in all stream sites. (b) Stream site altitude and catchment elevation range are the main explanatory variables for the differences in beta diversity; we predicted that local stream site variables would account for only minor amounts of variation. In both dry and wet seasons, we sampled twice in two habitat types (five leaf patches in pools and five in riffles) in each of nine stream sites distributed in three different river basins. We computed average pairwise beta diversity among sampling stations and seasons in each stream site by using Jaccard and Bray-Curtis indices, and calculated the percentages of diversity resulting from turnover and nestedness. Finally, we tested the degree that local- or catchment-level predictor variables explained beta diversity. We found that turnover was the main component of beta diversity and that both dissolved oxygen and elevation range best explained Bray-Curtis beta diversity. These results reinforce the importance of leaf patches in montane (sky islands) Neotropical savanna streams as biodiversity hotbeds for macroinvertebrates, and that both local and landscape variables explained beta diversity.

7.
Ecology ; 100(10): e02773, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31165481
8.
Mol Phylogenet Evol ; 132: 105-116, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30528540

RESUMEN

Even though Brazil is the world leader in amphibian diversity, a significant part of its richness remains unknown or hidden under cryptic taxa. Here, we used model-based species delimitation in an integrative taxonomic approach, by gathering molecular and morphometric data to assess cryptic taxa within the monkey frogs Pithecopus rohdei, from the Atlantic Forest, and P. megacephalus, from campos rupestres ecosystem. We sampled one mitochondrial, five nuclear loci, and 18 morphometric variables. Using species-delimitation methods with genetic and morphometric data, we recovered five divergent lineages within P. rohdei and no cryptic lineages were recovered for P. megacephalus. Morphometric data show differentiation only for one of the candidate species revealed by the delimitation approaches, suggesting that individuals from Doce River basin constitute a putative species for formal taxonomic description. The time-calibrated mtDNA tree shows that P. rohdei complex lineages began to diverge in late Miocene. However, dates from the multilocus species tree are more recent, occurring in Pleistocene, and suggesting their persistence in refuges of forest and sky islands within the Atlantic Forest biome. The existence of cryptic taxa within P. rohdei is, therefore, relevant for planning conservation strategies for this species complex in the Atlantic Forest biodiversity hotspot.


Asunto(s)
Anuros/clasificación , Biodiversidad , Animales , Teorema de Bayes , Brasil , Clima , Citocromos b/clasificación , Citocromos b/genética , ADN Mitocondrial/genética , Ecosistema , Bosques , Filogenia , Análisis de Componente Principal
9.
Front Plant Sci ; 9: 1745, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30564253

RESUMEN

Gomphrena marginata Seub. (Amaranthaceae) is an endemic species from Brazilian campos rupestres with a fructan accumulating underground reserve system. Analyses of high performance anion exchange chromatography (HPAEC-PAD) revealed the presence of the soluble carbohydrates glucose, fructose, sucrose, 1-kestose, 6-kestose, nystose and fructans with degree of polymerization (DP) up to approximately 40 fructose units. Data of 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopy, including Heteronuclear Single-Quantum Correlation (HSQC) and Heteronuclear Multiple-Bonds Correlation (HMBC) showed the presence of ß (2,6) linkages, characteristic of the linear molecule of levan-type fructan(2,6). These results confirmed previous studies suggesting that the reserve carbohydrate in the underground system of this species was levan-type fructans, similar to that of G. macrocephala. Structural analyses of the thickened underground system using light microscopy revealed a mixed origin system consisting mainly of a gemmiferous tuberous root with the upper region formed by short branched stems, both presenting vascular cylinders with unusual growth patterns. Fructan spherocrystals were visualized under polarized light and scanning electron microscopy (SEM) mostly in the cortex and vascular cylinder in both thickened stem and root. In addition to data reported in the literature concerning the occurrence of fructans in the Amaranthaceae, the results presented here suggest that fructans are a trait in this family while the levan-type fructan prevail in Gomphrena species.

10.
Ecol Evol ; 7(21): 8812-8828, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-29177033

RESUMEN

Protected areas (PAs) are essential for biodiversity conservation, but their coverage is considered inefficient for the preservation of all species. Many species are subdivided into evolutionarily significant units (ESUs) and the effectiveness of PAs in protecting them needs to be investigated. We evaluated the usefulness of the Brazilian PAs network in protecting ESUs of the critically endangered Pithecopus ayeaye through ongoing climate change. This species occurs in a threatened mountaintop ecosystem known as campos rupestres. We used multilocus DNA sequences to delimit geographic clusters, which were further validated as ESUs with a coalescent approach. Ecological niche modeling was used to estimate spatial changes in ESUs' potential distributions, and a gap analysis was carried out to evaluate the effectiveness of the Brazilian PAs network to protect P. ayeaye in the face of climate changes. We tested the niche overlap between ESUs to gain insights for potential management alternatives for the species. Pithecopus ayeaye contains at least three ESUs isolated in distinct mountain regions, and one of them is not protected by any PA. There are no climatic niche differences between the units, and only 4% of the suitable potential area of the species is protected in present and future projections. The current PAs are not effective in preserving the intraspecific diversity of P. ayeaye in its present and future range distributions. The genetic structure of P. ayeaye could represent a typical pattern in campos rupestres endemics, which should be considered for evaluating its conservation status.

11.
Braz. j. biol ; 77(4): 762-773, Nov. 2017. tab
Artículo en Inglés | LILACS | ID: biblio-888812

RESUMEN

Abstract Considering that the economic valuation of ecosystem services is a useful approach to support the conservation of natural areas, we aimed to estimate the monetary value of the benefits provided by a protected area in southeast Brazil, the Serra do Cipó National Park. We calculated the visitor's willingness to pay to conserve the ecosystems of the protected area using the contingent valuation method. Located in a region under intense anthropogenic pressure, the Serra do Cipó National Park is mostly composed of rupestrian grassland ecosystems, in addition to other Cerrado physiognomies. We conducted a survey consisting of 514 interviews with visitors of the region and found that the mean willingness to pay was R$ 7.16 year-1, which corresponds to a total of approximately R$ 716,000.00 year-1. We detected that per capita income, the household size, the level of interest in environmental issues and the place of origin influenced the likelihood that individuals are willing to contribute to the conservation of the park, as well as the value of the stated willingness to pay. This study conveys the importance of conserving rupestrian grassland and other Cerrado physiognomies to decision makers and society.


Resumo Dado que a valoração econômica de serviços ecossistêmicos é uma abordagem útil para incentivar a conservação de áreas naturais, tivemos como objetivo estimar o valor monetário dos benefícios fornecidos por uma área protegida no sudeste do Brasil, o Parque Nacional da Serra do Cipó. Calculamos a disposição a pagar dos visitantes pela conservação dos ecossistemas abrangidos pela área protegida, usando o método da valoração contingente. Localizado em uma região que sofre intensa pressão antrópica, o Parque Nacional da Serra do Cipó é composto majoritariamente por campos rupestres, além de outras fitofisionomias do Cerrado. Realizamos 514 entrevistas com os visitantes da região e encontramos uma disposição a pagar média de R$ 7,16 ano-1, o que corresponde ao total de aproximadamente R$ 716.000,00 ano-1. Detectamos que renda per capita, número de dependentes, nível de interesse por temas relacionados ao meio ambiente e local de origem influenciam a probabilidade de o indivíduo estar disposto a contribuir para a conservação do parque, assim como o valor da disposição a pagar declarada. Este estudo atrai atenção dos tomadores de decisão e da sociedade para a importância de se conservar os campos rupestres e outras fitofisionomias do Cerrado.


Asunto(s)
Ecosistema , Conservación de los Recursos Naturales/economía , Parques Recreativos/economía , Brasil
12.
Biota neotrop. (Online, Ed. port.) ; 17(1): e20160236, 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-838990

RESUMEN

Abstract Located in the municipalities of Ouro Preto and Mariana, in the Quadrilátero Ferrífero (QF) of Minas Gerais, the Itacolomi State Park (ISP) shelters more than 7,000 ha of remnants of Atlantic Forest and campos rupestres. The QF region has high biodiversity and is being highly impacted, mainly by mining activities. Aiming to organize the available floristic information and to support related research, this study presents the list of phanerogamic species of the ISP and the major vegetation types. This survey was carried out from October/1992 to July/2006, by monthly field trips. Besides authors´ personal collections, other records were assembled from herbarium databank. A total of 1623 taxons belonging to 122 families were listed. The families with higher species richness were Asteraceae, Fabaceae, Melastomataceae, Poaceae and Orchidaceae. The vegetation is represented by campos rupestres (51% of the total area), followed by montane forests (40%) and anthropogenic disturbed areas (9%). The greatest species richness occurs in campos rupestres. Several species are threatened and/or endemic. The knowledge of phanerogamic flora of ISP can help the Management Plan of this Unit of Conservation. It is also a contribution for future-related studies of the flora of ISP, Minas Gerais and Brazil.


Resumo O Parque Estadual do Itacolomi (PEIT) localiza-se nos municípios de Ouro Preto e Mariana, no Quadrilátero Ferrífero de Minas Gerais e abriga mais de 7.000 ha de remanescentes de mata atlântica e campos rupestres. A região do QF possui alta biodiversidade vegetal e está sobre alto impacto, principalmente pela mineração. O objetivo deste estudo foi apresentar a lista das espécies fanerogâmicas e os principais tipos vegetacionais desse Parque, no intuito de organizar a diversidade florística existente, além de servir como suporte para pesquisas correlatas subsequentes. O levantamento florístico foi realizado de outubro/1992 a julho/2006 por excursões mensais ao campo. Foram também incluídas na listagem registros ocorrentes em banco de dados de herbários. Foram identificados 1623 táxons, pertencentes à 122 famílias. As famílias mais representativas foram Asteraceae, Fabaceae, Melastomataceae, Poaceae e Orchidaceae. A vegetação do PEIT é constituída por campos rupestres (51% da área do parque), seguido pelas florestas montanas (40%) e por formações antrópicas (9%). A maior riqueza de espécies ocorre nos campos rupestres. Diversas espécies figuram em listas de espécies ameaçadas de extinção e outras são endêmicas. O conhecimento da flora fanerogâmica do Parque Estadual do Itacolomi pode subsidiar o Plano de Manejo dessa Unidade de Conservação e contribuir para futuros trabalhos correlatos nesta área, além de suprir conhecimentos para a flora de Minas Gerais e do Brasil.

13.
Mol Phylogenet Evol ; 97: 90-100, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26667031

RESUMEN

The remarkable diversity of Eupatorieae in the Brazilian flora has received little study, despite the tribe's very high levels of endemism and importance in the threatened Cerrado and the Atlantic Forest biodiversity hotspots. Eupatorieae are one of the largest tribes in Asteraceae with 14 of 19 recognized subtribes occurring in Brazil. We constructed the largest phylogeny of Brazilian Eupatorieae to date that sampled the nrITS and ETS, chloroplast ndhI and ndhF genes, and the ndhI-ndhG intergenic spacer for 183 species representing 77 of the 85 Brazilian genera of the tribe. Maximum likelihood and Bayesian phylogenetic analyses showed that these species are not collectively monophyletic, so their distribution reflects multiple introductions into Brazil. A novel clade was found that includes 75% of the genera endemic to Brazil (Cerrado-Atlantic Forest Eupatorieae, "CAFE" clade). This radiation of at least 247 species concentrated in the Cerrado and Atlantic Forest biomes of central eastern Brazil is <7 my old and exhibits several ecologically diverse life forms. Eight subtribes of Brazilian Eupatorieae (Ageratinae, Alomiinae, Ayapaninae, Critoniinae, Disynaphiinae, Eupatoriinae, Gyptidinae and Hebecliniinae) and 16 genera (Ageratum, Agrianthus, Austroeupatorium, Bejaranoa, Chromolaena, Critonia, Disynaphia, Grazielia, Hatschbachiella, Heterocondylus, Koanophyllon, Lasiolaena, Neocabreria, Praxelis, Stylotrichium, and Symphyopappus) were found to be polyphyletic. We attribute incongruities between the molecular phylogenetic results and the current classification of the tribe mostly to convergent evolution of morphological characters traditionally used in the classification of the tribe. We used these phylogenetic results to suggest changes to the classification of some subtribes and genera of Eupatorieae that occur in Brazil.


Asunto(s)
Asteraceae/clasificación , Asteraceae/genética , Bosques , Filogenia , Teorema de Bayes , Biodiversidad , Brasil , Cloroplastos/genética , Evolución Molecular , Funciones de Verosimilitud
14.
Braz. j. biol ; 75(1): 58-68, Jan-Mar/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-744325

RESUMEN

Interaction among species, like ants and plants through extrafloral nectaries (EFNs), are important components of ecological communities’ evolution. However, the effect of human disturbance on such specific interactions and its ecological consequences is poorly understood. This study evaluated the outcomes of mutualism between ants and the EFN-bearing plant Stachytarpheta glabra under anthropogenic disturbance. We compared the arthropod fauna composition between two groups of twenty plant individuals, one in an area disturbed by human activities and one in a preserved area. We also check the plant investment in herbivory defense and the consequential leaf damage by herbivore. Our results indicate that such disturbances cause simplification of the associated fauna and lack of proper ant mutualist. This led to four times more herbivory on plants of disturbed areas, despite the equal amount of EFN and ant visitors and low abundance of herbivores. The high pressure of herbivory may difficult the re-establishment of S. glabra, an important pioneer species in ferruginous fields, therefore it may affect resilience of this fragile ecological community.


As interações entre espécies, como por exemplo formigas e plantas através de nectários extraflorais (NEFs), são importantes componentes na evolução das comunidades. Entretanto, pouco é conhecido sobre os efeitos dos impactos antrópicos em interações específicas e suas consequências ecológicas. Este estudo avaliou os resultados do mutualismo entre formigas e NEF em Stachytarpheta glabra em área impactada pela atividade humana. Nós comparamos a composição e estrutura da fauna de artrópodes, em quarenta plantas de dois grupos, um impactado por atividades humanas e o outro preservado. Nós também avaliamos o investimento da planta em defesas contra herbívoros e os danos foliares causados por herbívoros. Nossos resultados indicam que os distúrbios causam a simplificação da fauna associada e a ausência de uma formiga mutualista anti-herbívoros. Isto leva a quatro vezes mais herbivoria nas plantas da área impactada, a despeito da mesma quantidade encontrada para NEF e formigas visitantes. A grande pressão de herbivoria pode dificultar o reestabelecimento de S. glabra, uma espécie pioneira importante nos campos ferruginosos, dessa forma, afetando a resiliência dessa comunidade ecológica ameaçada.


Asunto(s)
Animales , Humanos , Hormigas/clasificación , Simbiosis/fisiología , Verbenaceae/parasitología , Hormigas/fisiología , Conducta Animal , Actividades Humanas , Densidad de Población , Verbenaceae/clasificación
15.
Braz. j. biol ; 75(1): 39-48, Jan-Mar/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-744326

RESUMEN

Hummingbird communities tend to respond to variation in resources, having a positive relationship between abundance and diversity of food resources and the abundance and/or diversity of hummingbirds. Here we examined the influence of floral resource availability, as well as seasonality and type of habitat on the composition of hummingbird species. The study was carried out in two habitats of eastern Brazilian mountaintops. A gradient representative of the structure of hummingbird community, based on species composition, was obtained by the ordination of samples using the method of non-metric multidimensional scaling. The composition of hummingbird species was influenced by the type of habitat and floral resource availability, but not by seasonality. Hummingbird communities differ between habitats mainly due to the relative abundance of hummingbird species. The variation in composition of hummingbird species with the variation in floral resource availability may be related to differences in feeding habits of hummingbirds. Hummingbird species with the longest bills visited higher proportions of ornithophilous species, while hummingbirds with shorter bills visited higher proportions of non-ornithophilous species. The results demonstrate that at local-scale the composition of hummingbird species is affected by the type of habitat and floral resources availability, but not by seasonality.


Comunidades de beija-flores tendem a responder a variação em recursos, havendo uma relação positiva entre a abundância e diversidade de recurso alimentar com a abundância e/ou diversidade de beija-flores. Neste estudo nós analisamos a influencia da disponibilidade de recurso floral, bem como da sazonalidade e do tipo de habitat na composição de espécies de beija-flores. O estudo foi realizado em dois habitas de montanha do leste do Brasil. Um gradiente representativo da estrutura da comunidade de beija-flores, baseado na composição de espécies, foi obtido através da ordenação das amostras usando o método de escalonamento multidimensional não-métrico. A composição de espécies de beija-flores foi influenciada pelo tipo de habitat e disponibilidade de recurso floral, mas não pela sazonalidade. As comunidades de beija-flores variaram entre os habitas, principalmente devido a abundância relativa das espécies de beija-flores. A variação na composição de espécies de beija-flores com a variação na disponibilidade de recurso floral parece estar relacionada a diferenças nos hábitos alimentares dos beija-flores. Espécies de beija-flores com bicos de comprimentos maiores visitaram maiores proporções de espécies ornitófilas, enquanto beija-flores com bicos de comprimento menores visitaram maiores proporções de espécies não-ornitófilas. Os resultados demonstram que em escala local a composição de espécies de beija-flores é afetada pelo tipo de habitat e a disponibilidade de recurso floral, mas não pela sazonalidade.


Asunto(s)
Animales , Aves/clasificación , Ecosistema , Flores , Biodiversidad , Brasil , Conducta Alimentaria , Densidad de Población , Estaciones del Año
16.
Braz. j. biol ; 74(3)8/2014.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468200

RESUMEN

An inventory of the insect gall from Brazilian savanna (Cerrado) was elaborated based on samples of the collection of the Museu Nacional, Universidade Federal do Rio de Janeiro. Data on localities and host plants were obtained from the labels and information about the gall morphology (plant organ of occurrence, shape, and presence of trichomes) by observing the samples. The galling species was determined based on the literature. The collection includes 131 morphotypes of galls from Cerrado, obtained from 71 host plant species distributed in 50 genera and 30 botanical families (Table 1). All galls were collected in rupestrian fields (a rare vegetation physiognomy of the Brazilian Cerrado) in the state of Minas Gerais. As the collection comprises a great diversity of insect galls, it can be considered representative of this physiognomy.


Um levantamento de galhas de insetos do Cerrado brasileiro foi elaborado baseado em amostras da coleção do Museu Nacional/Universidade Federal do Rio de Janeiro. Dados de localidades e plantas hospedeiras foram obtidos das etiquetas e informações sobre a morfologia da galha (órgão vegetal de ocorrência, forma, e presença de tricomas) pela observação da amostra. As espécies galhadoras foram determinadas baseadas em literatura. A coleção inclui 131 morfotipos de galhas de Cerrado, obtidos de 71 espécies de plantas hospedeiras, distribuídas em 50 gêneros e 30 famílias botânicas (Tabela 1). Todas as galhas foram coletadas em campos rupestres (uma fisionomia vegetal rara do cerrado brasileiro) do Estado de Minas Gerais. Como a coleção compreende grande diversidade de galhas de insetos, pode ser considerada representativa para essa fisionomia.

17.
Braz. j. biol ; 74(3,supl.1): S207-S217, 8/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-732284

RESUMEN

An inventory of the insect gall from Brazilian savanna (Cerrado) was elaborated based on samples of the collection of the Museu Nacional, Universidade Federal do Rio de Janeiro. Data on localities and host plants were obtained from the labels and information about the gall morphology (plant organ of occurrence, shape, and presence of trichomes) by observing the samples. The galling species was determined based on the literature. The collection includes 131 morphotypes of galls from Cerrado, obtained from 71 host plant species distributed in 50 genera and 30 botanical families (Table 1). All galls were collected in rupestrian fields (a rare vegetation physiognomy of the Brazilian Cerrado) in the state of Minas Gerais. As the collection comprises a great diversity of insect galls, it can be considered representative of this physiognomy.


Um levantamento de galhas de insetos do Cerrado brasileiro foi elaborado baseado em amostras da coleção do Museu Nacional/Universidade Federal do Rio de Janeiro. Dados de localidades e plantas hospedeiras foram obtidos das etiquetas e informações sobre a morfologia da galha (órgão vegetal de ocorrência, forma, e presença de tricomas) pela observação da amostra. As espécies galhadoras foram determinadas baseadas em literatura. A coleção inclui 131 morfotipos de galhas de Cerrado, obtidos de 71 espécies de plantas hospedeiras, distribuídas em 50 gêneros e 30 famílias botânicas (Tabela 1). Todas as galhas foram coletadas em campos rupestres (uma fisionomia vegetal rara do cerrado brasileiro) do Estado de Minas Gerais. Como a coleção compreende grande diversidade de galhas de insetos, pode ser considerada representativa para essa fisionomia.


Asunto(s)
Animales , Insectos/clasificación , Tumores de Planta/clasificación , Brasil , Museos
18.
Braz. j. biol ; 74(3): 659-676, 8/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-723887

RESUMEN

The hummingbird-visited plant community located on the open-habitat mountaintop of the Espinhaço Range was studied for two years (from August 2007 to July 2009) in Serra do Cipó National Park, Southeastern Brazil (19° 15′ S and 43° 31′ W). The floral characteristics and flowering period of the hummingbird-visited plants was monthly recorded along trails located in three vegetation types: (1) typical campos rupestres (TCR), (2) open fields (OPF), and (3) capões de mata (CAM). Hummingbird visitation was observed in 51 plant species, 22 ornithophilous and 29 non-ornithophilous species. The TCR showed the greatest number of species visited (N = 38), followed by the OPF (N = 18) and CAM (N = 17). Six species of hummingbirds were recorded visiting flowers: Augastes scutatus, Campylopterus largipennis, Colibri serrirostris, Chlorostilbon lucidus, Eupetomena macroura and Phaethornis pretrei. This study demonstrates that the species richness and the number of ornithophilous species visited by the hummingbirds at the study site are more similar to hummingbird-plant communities of the Atlantic Forest than to those of the Cerrado communities and other Brazilian highland open-habitat communities. The plant families most visited by hummingbirds were Bromeliaceae and Asteraceae. Although the Asteraceae family is rarely used as a food resource for hummingbirds in other high and lowland communities, in the study site this family is used mainly by the endemic hummingbird Augastes scutatus. We found a large overlap of flowering throughout the year among the species visited by the hummingbirds. Thus, the nectar availability supports these resident hummingbirds. The present study also showed that the studied hummingbird-plant community is composed of many species endemic to the campos rupestres of the Espinhaço Range, some of which are considered to be in danger of extinction, thus constituting a unique and threatened community. Thus, understanding hummingbird-plant pollination dynamics becomes fundamental to the conservation of the campos rupestres.


A comunidade de flores visitadas por beija-flores em habitats abertos de montanhas da Serra do Espinhaço, sudeste do Brasil foi estudada por dois anos (de agosto de 2007 a julho de 2009) no Parque Nacional da Serra do Cipó (19° 15′ S e 43° 31′ W). As características florais e o período de floração das plantas visitadas foram registradas mensalmente ao longo de trilhas localizadas em três tipos vegetacionais: (1) campos rupestres típicos (TCR), (2) campos abertos (OPF), e (3) capões de mata (CAM). Foram observadas visitas de beija-flores a 51 espécies de plantas: 22 ornitófilas e 29 não-ornitófilas. O TCR apresentou o maior número de espécies visitadas (N = 38), seguido pelo OPF (N = 18) e CAM (N = 17). Seis espécies de beija-flores foram observadas visitando as flores: Augastes scutatus, Campylopterus largipennis, Colibri serrirostris, Chlorostilbon lucidus, Eupetomena macroura e Phaethornis pretrei. A riqueza de espécies e o número de espécies ornitófilas visitadas pelos beija-flores, neste estudo, foi mais similar à comunidades de plantas visitadas por beija-flores na Floresta Atlântica, que as comunidades do Cerrado, bem como de outras comunidades de ambientes abertos do Brasil. As famílias com maior número de plantas visitadas pelos beija-flores foram Bromeliaceae e Asteraceae. Apesar da família Asteraceae, raramente ser utilizada como fonte alimentar pelos beija-flores em outras comunidades, nas áreas amostradas neste estudo esta família foi utilizada, principalmente, pelo beija-flor endêmico A. scutatus. Nós registramos grande sobreposição de floração ao longo do ano entre as espécies visitadas pelos beija-flores. Portanto, a disponibilidade de néctar mantem os beija-flores residentes. Este estudo, demonstrou também, que a comunidade de plantas visitadas pelos beija-flores nesta área é composta por muitas espécies endêmicas dos campos rupestres da Serra do Espinhaço, algumas das quais consideradas em perigo de extinção, constituindo assim uma comunidade única e ameaçada. Portanto, o entendimento da dinâmica de polinização desta comunidade é fundamental para a conservação dos campos rupestres.


Asunto(s)
Animales , Aves/fisiología , Conducta Alimentaria/fisiología , Flores/clasificación , Brasil , Aves/clasificación , Néctar de las Plantas , Densidad de Población , Estaciones del Año
19.
Mol Ecol ; 23(12): 3044-63, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24803224

RESUMEN

The role of Pleistocene climate changes in promoting evolutionary diversification in global biota is well documented, but the great majority of data regarding this subject come from North America and Europe, which were greatly affected by glaciation. The effects of Pleistocene changes on cold- and/or dry-adapted species in tropical areas where glaciers were not present remain sparsely investigated. Many such species are restricted to small areas surrounded by unfavourable habitats, which may represent potential interglacial microrefugia. Here, we analysed the phylogeographic structure and diversification history of seven cactus species in the Pilosocereus aurisetus complex that are restricted to rocky areas with high diversity and endemism within the Neotropical savannas of eastern South America. We combined palaeodistributional estimates with standard phylogeographic approaches based on two chloroplast DNA regions (trnT-trnL and trnS-trnG), exon 1 of the nuclear gene PhyC and 10 nuclear microsatellite loci. Our analyses revealed a phylogeographic history marked by multiple levels of distributional fragmentation, isolation leading to allopatric differentiation and secondary contact among divergent lineages within the complex. Diversification and demographic events appear to have been affected by the Quaternary climatic cycles as a result of isolation in multiple patches of xerophytic vegetation. These small patches presently harbouring P. aurisetus populations seem to operate as microrefugia, both at present and during Pleistocene interglacial periods; the role of such microrefugia should be explored and analysed in greater detail.


Asunto(s)
Evolución Biológica , Cactaceae/clasificación , Filogenia , Teorema de Bayes , Cactaceae/genética , Cambio Climático , ADN de Cloroplastos/genética , ADN de Plantas/genética , Genética de Población , Repeticiones de Microsatélite , Modelos Biológicos , Datos de Secuencia Molecular , Filogeografía , Análisis de Secuencia de ADN , América del Sur
20.
Biota neotrop. (Online, Ed. port.) ; 14(1): 1-15, 2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-707022

RESUMEN

This study identified patterns of geographic distribution of 102 Leguminosae taxa within the Park, based on literature data and herbarium specimens. Among the taxa, 38 grow exclusively in Campos Rupestres (rocky fields) and 49 in the Semideciduous Forest. Eleven patterns of geographic distribution were identified, of which the West-East-Central South America pattern was the most representative, with 27 taxa. Of the 102 sampled taxa of Leguminosae, five are endemic to the Espinhaço Range and ten are included in lists of endangered species of the flora of Brazil and Minas Gerais. Information on these taxa is crucial to provide conservation practices for conserving the vegetation formations of the PEIT.


Neste estudo foram identificados os padrões de distribuição geográfica dos 102 táxons de Leguminosae ocorrentes no PEIT, com base nos dados obtidos na literatura e em material de herbário, sendo 38 exclusivos dos Campos Rupestres e 49 das Florestas Estacionais. Foram reconhecidos 11 padrões de distribuição geográfica, dos quais o padrão América do Sul Ocidental-Centro-Oriental foi o mais representativo com 27 táxons. Dos 102 táxons amostrados de Leguminosae, cinco são endêmicos da Cadeia do Espinhaço e 10 constam nas listas de espécies ameaçadas da flora brasileira ou da Flora de Minas Gerais, sendo consideradas importantes para fornecer subsídios na conservação das formações vegetacionais do PEIT.

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