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1.
Mol Ecol ; 32(12): 3165-3181, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36934376

RESUMO

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.


Assuntos
Variação Genética , Animais , Filogeografia , Filogenia , Teorema de Bayes , Brasil , Demografia
2.
An Acad Bras Cienc ; 93(suppl 4): e20200973, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730616

RESUMO

Hohenbergia lanata Pereira & Moutinho is an endemic bromeliad of the State of Bahia (Brazil), occurring in an altitudinal transition forest between Caatinga dry woodland and Atlantic Forest. The type material was collected by Roberto Burle-Marx, who introduced it into cultivation in his gardens, but lacking the accurate provenance, only mentioning that it was collected between Milagres and Amargosa municipalities. It was later described by Pereira & Moutinho based on a cultivated specimen. In this work, we present new specimens found in natural populations in an area that coincides with the type locality description, enabling us to expand the description of the species, as well as to provide images of the living plants in the field, adding information about its habitat. The herbarium collections revision and the new population found in the field enabled us to propose an updated conservation status and to better characterize the habit, plant architecture, and to add new morphological comparisons and geographical distribution.


Assuntos
Bromeliaceae , Ecossistema , Brasil , Florestas , Plantas
3.
PhytoKeys ; (86): 43-74, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29033668

RESUMO

A National Forest Inventory (NFI) encompassing the entire territory of Brazil is in progress. It is coordinated and promoted by the Brazilian Forest Service of the Ministry of Environment. In each state, the NFI collaborates with local herbaria by receiving collected plant material and performing species identification. Consultants are hired by the NFI and work at the local herbaria under the supervision of a curator. In exchange for curatorial assistance, the NFI provides equipment and consumables for the herbarium. Other public projects collaborating with NFI are Reflora and the Brazilian Biodiversity Information System (SiBBr). Both projects have online platforms that seek to connect herbaria and make all their data freely available, including high quality digital images of specimens. Through inter-institutional collaboration, the joint interests of NFI, Reflora, SiBBr and local herbaria have improved collections, expanded the online Reflora database, and provided the NFI with verified species lists. These strategic uses of public funding are positively affecting Botany, particularly during a period of economic crisis and cuts in research. Here, we illustrate the increase in floristic knowledge through the improvement of a herbarium collection in Rio Grande do Norte (RN) - the Brazilian state with the lowest levels of plant richness. We report 71 new occurrences of vascular plants for RN, belonging mainly to the Poaceae, Fabaceae and Malvaceae. Most of the species with new occurrences have a Neotropical distribution (21 spp.) and only seven are restricted to the Brazilian Northeast. Our findings highlight previous gaps in RN's floristic knowledge. The partnership NFI, Reflora, SiBBr and the UFRN herbarium improved herbarium curation, digital collection, and quality of data. Finally, a fellowship provided by Reflora and SiBBr allowed improving curation by distributing duplicates and incorporating the Herbarium of Câmara Cascudo Museum.

4.
Am J Bot ; 101(7): 1167-1175, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25030351

RESUMO

• Premise of the study: Knowledge about genetic variability in plant populations is one of the main branches of conservation genetics, linking genetic data to conservation strategies. Vriesea minarum is a bromeliad endemic to the Iron Quadrangle region (southeastern Brazil), occurring on mountaintop rock outcrops. It is listed as endangered due to habitat loss, particularly from iron ore mining. Thus, determining the structure and genetic diversity of V. minarum populations could help develop strategies to conserve the species.• Methods: We studied the genetic structure of 12 populations of V. minarum using 10 microsatellite loci transferred from other species of Bromeliaceae. Statistical analyses to compare and describe the genetic diversity of each population were performed, and genetic structure within and among populations, isolation by distance, and Bayesian structure were also analyzed.• Key results: Our results show high inbreeding (GIS = 0.376) and low population structure (FST = 0.088), possibly related to high gene flow due to great pollinator efficiency and/or efficient seed dispersal, thus leading to high connectivity among populations of these fragmented rock outcrops. Two clusters were observed, corresponding to the basins of rivers São Francisco and Doce.• Conclusions: Gene flow among populations is high but, given the rate of habitat loss to mining, most populations are vulnerable and will become increasingly isolated if no action is taken to preserve them. Thus, conservation of this species depends on in situ and ex situ actions, such as controlling overexploitation and creating a germoplasm bank.

5.
Mol Phylogenet Evol ; 64(1): 177-89, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22491070

RESUMO

The genus Alcantarea comprises near 30 species endemic to rocky outcrops from eastern Brazil. Most species are ornamental and several are threatened due to habitat loss and over collection. In this paper we examine the phylogenetics of Alcantarea and its relationship with the Brazilian members of Vriesea, a genus of which Alcantarea has been treated as a subgenus. We discuss the morphological evolution of the stamen position and its implication for pollination and the occurrence of Alcantarea in the Espinhaço mountain range rocky savanna-like habitat vegetation. DNA sequence data derived from two plastid markers (trnK-rps16, trnC-petN) and from a low copy nuclear gene (Floricaula/Leafy) together with 20 nuclear microsatellite loci were the data source to perform analyses and construct phylogenetic and Neighbor Joining trees for the genus. Alcantarea is well supported as monophyletic in both Bayesian and parsimony analyses, but sections of Vriesea, represented by the eastern Brazilian species, appear paraphyletic. Microsatellites delimit geographically isolated species groups. Nevertheless individuals belonging to a single species may appear related to distinct clusters of species, suggesting that hybridization and/or homoplasy and/or incomplete lineage sorting are also influencing the analysis based on such markers and may be the reasons for some unexpected results. Alcantarea brasiliana is hypothesized as putative hybrid between A. imperialis and A. geniculata. Spreading stamens, a morphological floral characteristic assumed to be related to Chiropterophily, apparently evolved multiple times within the genus, and invasion of rocky savanna-like habitat vegetation by Atlantic rainforest ancestors seems to have occurred multiple times as well.


Assuntos
Evolução Biológica , Bromeliaceae/anatomia & histologia , Bromeliaceae/genética , Ecossistema , Filogenia , Sequência de Bases , Teorema de Bayes , Brasil , Núcleo Celular/genética , DNA de Cloroplastos/genética , Flores/anatomia & histologia , Hibridização Genética , Repetições de Microssatélites/genética , Modelos Genéticos , Dados de Sequência Molecular , Filogeografia , Análise de Sequência de DNA
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