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1.
Mol Biol Rep ; 51(1): 582, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678168

RESUMO

BACKGROUND: Hybridization associated with polyploidy studies is rare in the tropics. The genus Zygopetalum (Orchidaceae) was investigated here as a case study of Neotropical plants. In the rocky highlands of the Ibitipoca State Park (ISP), southeast Brazil, individuals with intermediate colors and forms between the species Z. maculatum and Z. triste were commonly identified. METHODS AND RESULTS: Chromosomal analysis and DNA quantity showed a uniform population. Regardless of the aspects related to the color and shape of floral structures, all individuals showed 2n = 96 chromosomes and an average of 14.05 pg of DNA. Irregularities in meiosis associated with chromosome number and C value suggest the occurrence of polyploidy. The genetic distance estimated using ISSR molecular markers revealed the existence of genetic variability not related to morphological clusters. Morphometric measurements of the flower pieces revealed that Z. maculatum shows higher variation than Z. triste although lacking a defined circumscription. CONCLUSION: The observed variation can be explained by the polyploid and phenotypic plasticity resulting from the interaction of the genotypes with the heterogeneous environments observed in this habitat.


Assuntos
Variação Genética , Orchidaceae , Fenótipo , Poliploidia , Orchidaceae/genética , Variação Genética/genética , Brasil , Cromossomos de Plantas/genética , Genótipo , Flores/genética , Flores/anatomia & histologia , Repetições de Microssatélites/genética , Hibridização Genética/genética
2.
Biodivers Data J ; 12: e105688, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38235164

RESUMO

Background: Inselbergs are granitic and/or gneissic rocky outcrops and, in Brazil, the dome-shaped ones in the Atlantic Forest Domain are called sugarloaves (pães de açúcar). They have an extremely specialised vegetation with high levels of endemism. Even though, they are poorly studied and highly degraded. In north-eastern Espírito Santo State, south-eastern Brazil, the Monumento Natural dos Pontões Capixabas (MONAPC) is a federal protected area created to guard some inselbergs mainly threatened by mining, which is one of the main economic activities in the State. In this work, we provide the first checklist of the vascular plant species in this protected area. New information: We recorded 108 species in 36 families and 75 genera that inhabit the vegetation islands on the inselbergs within the official limits of MONAPC. A new species of Pleroma (Melastomataceae) and a new species of Cololobus (Asteraceae) were discovered as new to science and they are being described in other articles.

3.
Environ Manage ; 71(2): 483-493, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36459196

RESUMO

The application of the mitigation hierarchy (MH) to mining projects is challenging in situations of locational overlap between endemic flora and mineral deposits. We review flora surveys conducted in connection with the environmental impact assessment of several iron ore mining projects in an area of high degree of endemism in Eastern Amazon to discuss the practical implications of anticipating conservation strategies. Desktop studies and secondary data review were conducted to guide field searches to determine the distribution of endemic flora, resulting in 45 out of 46 endemic plant species having their known distribution extended to new areas. A framework for positioning flora conservation strategies in the MH is presented. Specific habitat requirements and scarce knowledge about endangered and endemic flora species are a conservation obstacle, since essential information to define species conservation strategies may be lacking. We show that anticipating conservation strategies can minimize time-lag uncertainties related to restoration success and biodiversity offsets. The more effort is placed in the preventative steps of the MH, the smaller the time-lag between impact (biodiversity losses) and conservation outcomes (biodiversity gains), decreasing uncertainties and reducing risks to biodiversity.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Biodiversidade , Mineração
5.
Acta sci., Biol. sci ; Acta sci., Biol. sci;43: e54760, 2021. map, ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460970

RESUMO

Inselbergs are granitic or gneissic rocky outcrops prevalent in the landscape of southeastern Brazil. These ecosystems represent islands of isolated habitats that harbor a peculiar flora with high richness and endemism. The present study lists the species of vascular plants occurring in the Pedra da Andorinha Complex, located in the municipality of Jerônimo Monteiro/Cachoeiro de Itapemirim, southern Espírito Santo state, aiming to generate subsidies for the creation of a protected area. The survey was performed between July 2017 and October 2018, resulting in a record of 121 species, 96 genera, and 40 families. Bromeliaceae (17), Orchidaceae (12) and Fabaceae (10) were the richest families. The phytophysiognomy of exposed rock vegetation comprises a greater number of species (79 species) compared to the woody rupicolous communities (42). Eighteen of the collected species are threatened by extinction; a new species was discovered; and five were described based on materials previously collected in the studied location — Alcantarea patriae, Anthurium martinellii, Coleocephalocereus uebelmanniorum, Stigmatodon attenuatoides and Pitcairnia azouryi, the first four being endemic to the region. We also found Tabebuia reticulata, a rare species among Brazilian flora. Our results highlight the biological importance of the Pedra das Andorinhas Complex and reinforce the need to create a protected area to preserve biodiversity and the regional natural heritage.


Assuntos
Biodiversidade , Florestas , Traqueófitas/anatomia & histologia , Traqueófitas/crescimento & desenvolvimento
6.
Acta Sci. Biol. Sci. ; 43: e54760, 2021. mapas, ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-19166

RESUMO

Inselbergs are granitic or gneissic rocky outcrops prevalent in the landscape of southeastern Brazil. These ecosystems represent islands of isolated habitats that harbor a peculiar flora with high richness and endemism. The present study lists the species of vascular plants occurring in the Pedra da Andorinha Complex, located in the municipality of Jerônimo Monteiro/Cachoeiro de Itapemirim, southern Espírito Santo state, aiming to generate subsidies for the creation of a protected area. The survey was performed between July 2017 and October 2018, resulting in a record of 121 species, 96 genera, and 40 families. Bromeliaceae (17), Orchidaceae (12) and Fabaceae (10) were the richest families. The phytophysiognomy of exposed rock vegetation comprises a greater number of species (79 species) compared to the woody rupicolous communities (42). Eighteen of the collected species are threatened by extinction; a new species was discovered; and five were described based on materials previously collected in the studied location — Alcantarea patriae, Anthurium martinellii, Coleocephalocereus uebelmanniorum, Stigmatodon attenuatoides and Pitcairnia azouryi, the first four being endemic to the region. We also found Tabebuia reticulata, a rare species among Brazilian flora. Our results highlight the biological importance of the Pedra das Andorinhas Complex and reinforce the need to create a protected area to preserve biodiversity and the regional natural heritage.(AU)


Assuntos
Traqueófitas/anatomia & histologia , Traqueófitas/crescimento & desenvolvimento , Florestas , Biodiversidade
7.
Plant Biol (Stuttg) ; 19(4): 592-598, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28244194

RESUMO

Some parasitic plants are capable of vegetative propagation, which allows them access to new hosts and improves nutrient availability. We aimed to determine what factors positively influence this propagation in the xylem-tapping Struthanthus flexicaulis, focusing on the use of directed foraging as a means of optimising access to resources. The study site was a rupicolous plant community in southeast Brazil. We evaluated how the success of branch propagation (by contagion) of the mistletoe is influenced by the crown height and density of its main host, the legume Mimosa calodendron. Oriented foraging was tested through comparing the response of mistletoe branches toward a potential host (resources) or a plastic net (no resources). Successful contagion was related to high density and the departure height of a branch from a host crown. In a high-density area, 89% of branches reached a new host versus 21% in a low-density area. Formation of an appressorium on either the plastic nets or hosts elicited branch growth reorientation towards it, as well as development of new branches. These responses were significantly stronger towards hosts than nets, and attributed to effective xylem tapping. The foraging strategy of S. flexicaulis benefits from branch response (growth and reorientation) to the development of appressoria and their resulting haustoria. The growth of appressoria on non-resource substrates and the ensuing response optimises the mistletoe spread by allowing these substrates to act as physical support for spreading branches and to infect a host that was previously out of reach.


Assuntos
Loranthaceae/crescimento & desenvolvimento , Loranthaceae/fisiologia , Brasil , Fabaceae/parasitologia , Xilema/fisiologia
8.
Biota neotrop. (Online, Ed. port.) ; 13(4): 113-120, Oct-Dec/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-703571

RESUMO

Bromeliaceae is one of the most relevant taxonomic groups of the Atlantic Forest, where the Brazilian southeastern region stands out as a center of diversity and endemism for many taxa of the family. We present a checklist of the 12 genera and 44 species of Bromeliaceae from the Pedra dos Pontões, in Mimoso do Sul municipality, Espírito Santo state, southeastern Brazil. The Bromelioideae (22 species) was the subfamily with most taxonomic diversity, followed by Tillandsioideae (18 species) and Pitcairnioideae (four species). We also report the first occurrence of four species (A. squarrosa, N. antoineanum, V. pseudoatra and V. pardalina) for the Espírito Santo state. Almost half of the taxa surveyed inhabit exclusively the vegetation associated to the rocky outcrops, what points out the importance of this kind of environment in the maintenance of the diversity for many species of bromeliads. We also highlight that the documentation and study of the flora of Espírito Santo, which is considered a gap in the knowledge of the plant diversity along the entire Brazilian Atlantic Forest, assumes a relevant aspect in view of the high levels of degradation of the natural ecosystems observed in the state.


Bromeliaceae é um dos grupos taxonômicos mais relevantes da Floresta Atlântica, onde o sudeste do Brasil se destaca como um centro de diversidade e endemismo de muitos táxons da família. Nós apresentamos uma lista de 12 gêneros e 44 espécies de Bromeliaceae da Pedra dos Pontões, no município de Mimoso do Sul, estado do Espírito Santo, sudeste do Brasil. Bromelioideae (22 espécies) foi a subfamília com maior diversidade taxonômica, seguida por Tillandsioideae (18 espécies) e Pitcairnioideae (quatro espécies). Nós também reportamos a primeira ocorrência de quatro espécies (A. squarrosa, N. antoineanum, V. pseudoatra e V. pardalina) para o estado do Espírito Santo. Quase a metade dos táxons levantados habita exclusivamente a vegetação associada ao afloramento rochoso, o que ressalta a importância deste tipo de ambiente na manutenção da diversidade de muitas espécies de bromélias. Destacamos também que a documentação e estudo da flora do Espírito Santo, considerada uma lacuna no conhecimento da diversidade de plantas ao longo da Floresta Atlântica, assume um aspecto relevante tendo em vista os altos níveis de degradação dos ecossistemas naturais observados no estado.

9.
Iheringia, Sér. zool ; 101(4)Set. 2011.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1482657

RESUMO

New material of Pristimantis crepitans (Bokermann, 1965) was obtained from rocky outcrops located in southwestern borders of the Cerrado biome from central Brazil, and in the western border of the Pantanal wetlands, in the boundaries between Brazil and Bolivia. Individuals were collected and recorded in the type-locality and in four additional municipalities, in two mid-western Brazilian states: Mato Grosso and Mato Grosso do Sul. Besides range extension and morphometric data additional to those in the original description, we here provide a description of the topotypical vocalization of P. crepitans, as well as photographs of live specimens and of some of their habitats, for the first time in the literature.


Espécimes de Pristimantis crepitans (Bokermann, 1965) foram obtidos em áreas de afloramentos rochosos situadas na borda sudoeste do Cerrado e na borda oeste do Pantanal, próximo à fronteira entre o Brasil e a Bolívia. Indivíduos foram coletados e gravados na localidade-tipo e em outros quatro municípios, nos estados de Mato Grosso e Mato Grosso do Sul. Além da ampliação da área de ocorrência e de dados morfométricos adicionais aos da série-tipo, apresentamos pela primeira vez na literatura parâmetros da vocalização topotípica de P. crepitans, bem como fotografias de espécimes em vida e de alguns dos hábitats ocupados pelos mesmos.

10.
Biota neotrop. (Online, Ed. port.) ; 11(2): 255-268, Apr.-June 2011. graf, tab
Artigo em Inglês | LILACS | ID: lil-596881

RESUMO

Vascular species and their respective life-forms and coverage were recorded in a Brazilian quartzite and itabirite rocky outcrop site at Serra de Ouro Preto, producing the floristic, frequency and vegetational spectra. Three habitats in both lithologies were defined by geomorphology as: 1) Sloped areas near the mountain summit, with grasslands; 2) Plateaus in the middle of the slope, with grasslands; and 3) Lower and/or concave parts of the slopes, with woody savannas. The life-forms followed Raunkiaer's System. We aimed to answer the following questions: Do quartzite and itabirite rocky outcrops have different biological spectra? Are the biological spectra different in the geomorphologic habitats? Do the floristic, vegetational and frequency spectra differ from one another? What spectrum stacks up to a rocky outcrop physiognomy description? The results portrayed that: a) the most represented life-forms were the phanerophytes and hemicryptophytes; b) the floristic and frequency spectra did not differ from each other, but both differed from the vegetational one; c) all the floristic spectra were similar, but there were significant differences in the frequency and vegetational spectra among the lithology and geomorphology habitats; d) higher phanerophyte and lesser hemicryptophyte coverages were found in the itabirite areas and also in the lower or concave parts of the slopes of both lithologies; and e) the vegetational spectrum was more efficient for the studied rocky outcrop comparison. Relationships between the environmental aspects and life-form spectra are discussed. This study will help advance the development of restoration projects for these areas by adding knowledge of their flora composition, structure and function.


Realizou-se um levantamento das espécies vasculares e suas respectivas formas de vida e coberturas, em campos rupestres na Serra de Ouro Preto, sobre quartzito e itabirito, para construção dos espectros florísticos, de freqüência e vegetacional. Em cada litologia foram delimitados, pela geomofologia, três tipos de habitats: 1) Áreas inclinadas, nos topos das montanhas, com campos limpos; 2) Platôs, na parte mediana das encostas, com campos limpos e 3) Partes mais baixas ou côncavas das encostas, com campos sujos. As formas de vida seguiram o sistema de Raunkiaer. Averiguaram-se as seguintes questões: Campos rupestres sobre itabirito e quartzito possuem diferentes espectros biológicos? Os habitats estratificados pela geomorfologia diferem quanto aos espectros biológicos? Os espectros florísticos, de frequência e vegetacional diferem entre si? Qual espectro se destaca como descritor da fisionomia de campos rupestres? Os resultados evidenciaram que: a) fanerófitas e hemicriptófitas são as formas de vida predominantes; b) os espectros florísticos e de frequência não diferiram entre si e ambos foram estatisticamente diferentes do espectro vegetacional; c) os habitats estratificados pela litologia e geomorfologia apresentaram espectros florísticos similares, mas os espectros de frequência e vegetação mostraram diferenças significativas; d) maior cobertura de fanerófitas e menor cobertura de hemicriptófitas foram encontradas nas áreas sobre itabirito, assim como nas partes mais baixas ou côncavas das encostas, em ambas litologias; e e) o espectro vegetacional mostrou-se mais eficiente para comparação dos habitats. Aspectos do ambiente relacionados com a distribuição de formas de vida são discutidos. Este estudo subsidia programas de restauração ambiental, ampliando o conhecimento da vegetação de campos rupestres.

11.
Artigo em Português | VETINDEX | ID: vti-437813

RESUMO

New material of Pristimantis crepitans (Bokermann, 1965) was obtained from rocky outcrops located in southwestern borders of the Cerrado biome from central Brazil, and in the western border of the Pantanal wetlands, in the boundaries between Brazil and Bolivia. Individuals were collected and recorded in the type-locality and in four additional municipalities, in two mid-western Brazilian states: Mato Grosso and Mato Grosso do Sul. Besides range extension and morphometric data additional to those in the original description, we here provide a description of the topotypical vocalization of P. crepitans, as well as photographs of live specimens and of some of their habitats, for the first time in the literature.


Espécimes de Pristimantis crepitans (Bokermann, 1965) foram obtidos em áreas de afloramentos rochosos situadas na borda sudoeste do Cerrado e na borda oeste do Pantanal, próximo à fronteira entre o Brasil e a Bolívia. Indivíduos foram coletados e gravados na localidade-tipo e em outros quatro municípios, nos estados de Mato Grosso e Mato Grosso do Sul. Além da ampliação da área de ocorrência e de dados morfométricos adicionais aos da série-tipo, apresentamos pela primeira vez na literatura parâmetros da vocalização topotípica de P. crepitans, bem como fotografias de espécimes em vida e de alguns dos hábitats ocupados pelos mesmos.

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