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1.
Cladistics ; 37(4): 442-458, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34478191

RESUMEN

Brazil has high levels of biodiversity and has received strong criticism for the increasing country-wide deforestation that threatens it. Although a significant percentage of land area in Brazil is protected, the areas are insufficient and unevenly distributed. Many studies have contributed to the biogeographical knowledge of Brazilian flora, but no endemicity analysis (EA) has been conducted including all endemic angiosperms. We investigated the spatial component, drawing on a huge and taxonomically diverse dataset based on 827 016 records collected over the last two centuries. We conducted an EA for 15 034 species from 173 families using an optimality criterion with 2° and 3° grid sizes, in order to search for distributional concordance, to identify the biogeographical units and discuss the implications for conservation. Six analyses were run for basal angiosperms, monocots and eudicots. The EA recovered 66 consensus areas (CAs). The concordance of CAs enabled the identification of five best-supported areas of endemism--three in the Atlantic and Parana Forest and two areas in the Cerrado province--supported by species of 120 families. The age of divergence for some genera that contributed significantly to the identification of areas recovered in the Cerrado coincides with the recent, <10 Ma, estimated age of that province. By contrast, the areas in the Atlantic and Parana Forest are supported by genera with earlier diversification >30 Ma, supporting an ancient origin. Most areas in the Atlantic Forest are partially superimposed with the limits of the protected areas, however, big gaps were identified in the Cerrado. Protecting Brazilian biomes was at the heart of Brazil's environmental policy. Regrettably, this scenario has radically changed based on misleading divergences in conservation policy. Areas of endemism are pivotal for biodiversity conservation due to the common evolutionary history shared by their endemic taxa. Thus, we hope that these congruent patterns of endemism support the establishment of biodiversity priorities.


Asunto(s)
Biodiversidad , Evolución Biológica , Conservación de los Recursos Naturales , Magnoliopsida/fisiología , Filogenia , Brasil , Bosques
2.
Proc Natl Acad Sci U S A ; 114(40): 10695-10700, 2017 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-28923966

RESUMEN

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.


Asunto(s)
Biodiversidad , Bases de Datos Factuales , Plantas/clasificación , Bosque Lluvioso , Brasil
3.
J Hered ; 106(1): 93-101, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25472982

RESUMEN

Encholirium horridum is a bromeliad that occurs exclusively on inselbergs in the Atlantic Forest biome of Brazil. These rock outcrops form natural islands that isolate populations from each other. We investigated gene flow by pollen through paternity analyses of a bromeliad population in an area of approximately 2 ha in Espírito Santo State, Brazil. To that end, seed rosettes and seedlings were genotyped using nuclear microsatellite loci. A plot was also established from the same population and specimens were genotyped to evaluate their fine-scale spatial genetic structure (SGS) through analyses of spatial autocorrelation and clonal growth. Paternity analysis indicated that 80% of the attributed progenitors of the genotyped seedlings were from inside the study area. The pollen dispersal distances within the area were restricted (mean distance of 45.5 m, varying from 3 to 156 m) and fine-scale SGS was weak (F(ij) = 0.0122, P < 0.001; Sp = 0.009). Clonal growth was found to be a rare event, supporting the monocarpy of this species.


Asunto(s)
Bromeliaceae/genética , Demografía , Especies en Peligro de Extinción , Flujo Génico/genética , Variación Genética , Dispersión de Semillas/fisiología , Brasil , Bromeliaceae/crecimiento & desarrollo , Bosques , Genética de Población , Genotipo , Repeticiones de Microsatélite/genética , Polen/genética , Dispersión de Semillas/genética
4.
Rev Biol Trop ; 62(2): 829-41, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25102662

RESUMEN

The Brazilian Atlantic Forest presents high levels of richness and endemism of several taxonomic groups. Within this forest, the Orchidaceae may be highlighted as the richest family of Angiosperms found there, and is highly threatened due to collection and habitat destruction. The inselbergs of the Brazilian Atlantic Forest are mostly unknown regarding their floristic composition, but the available information points to occurrence of endemic species, with adaptations to survive to this dry environment. The objectives of this study were to conduct a floristic survey of the Orchidaceae species on the Maciço do Itaoca, an inselberg located in the Northern region of the State of Rio de Janeiro, make a comparative analysis with other sites in Eastern Brazil, and discuss the geographic distribution, floristic relationships and conservation status of the orchid species present on the inselbergs. The floristic composition of the study area was compared with 24 other locations in Eastern Brazil (of which 13 are inselbergs) and the influence of the types of surrounding vegetation on the composition of the Orchidaceae flora on the inselbergs. On Maciço do Itaoca we recorded 18 species from 17 genera: Brasiliorchis picta, Brassavola tuberculata, Campylocentrum robustum; C sellowii, Catasetum luridum, Cattleya guttata, Cyclopogon congestus, Cyrtopodium glutiniferum, Leptotes bicolor, Lophiaris pumila, Miltonia moreliana, Oeceoclades maculata, Phymatochilum brasiliense, Prescottia plantaginifolia, Pseudolaelia vellozicola, Sarcoglottis fasciculata, Sophronitis cernua. and Vanilla chamissonis. The highest floristic similarity was with the Pedra da Botelha (0.43), an inselberg located in the North of Espírito Santo. This result is probably due to the similarity in altitude and distance from the coast in both areas despite the geographical distance between them. Apparently, little influence is exerted by the types of surrounding vegetation on the composition of the flora of inselbergs, due to their unique environmental characteristics which exert a strong selection pressure on plants that are adapted to survive on these inselbergs. The threats observed to the species on this inselberg are the same as for other inselbergs and include the collection of ornamental species, fire and quarrying. Specifically for the Maciço do Itaoca, a possibility for conservation may be the annexation of this area to the Desengano State Park, an important conservation area in the Northern of the State of Rio de Janeiro.


Asunto(s)
Conservación de los Recursos Naturales , Orchidaceae/clasificación , Árboles , Biodiversidad , Brasil , Geografía
5.
Biodivers Data J ; 12: e105688, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38235164

RESUMEN

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.

6.
PhytoKeys ; 243: 137-148, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38957681

RESUMEN

Strychnos (Loganiaceae, Gentianales) is a large and pantropical genus of woody plants, ethnobotanically important as a source of many toxic alkaloids, including strychnine. Unfortunately, the status of numerous names at various ranks of Strychnos remains unresolved, including that of many specific or infraspecific taxa in the Neotropics. In this study, we address Strychnosbredemeyeri (basionym Lasiostomabredemeyeri), a species described in 1827 based on type material collected in Venezuela during the poorly documented Austrian Märter expedition (1783-1788). Strychnosbredemeyeri is an unarmed liana with solitary tendrils and axillary inflorescences that occurs in Neotropical rainforests and savannas in Brazil, Guyana, Trinidad and Tobago, and Venezuela. We clarify here the nomenclatural status of Lasiostoma Schreb., an illegitimate and superfluous genus currently in synonymy under Strychnos, and its former species Lasiostomabredemeyeri [= Strychnosbredemeyeri]. Also, we lectotypify S.pedunculata and S.trinitensis, both taxa currently synonyms of S.bredemeyeri.

7.
Biodivers Data J ; 9: e66043, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34121849

RESUMEN

BACKGROUND: Herbarium collections and the data they hold are the main sources of plant biodiversity information. These collections contain taxonomical and spatial data on living and extinct species; consequently, they are the fundamental basis for temporal and spatial biogeographical studies of plants. Mega projects focused on providing digital and free access to accurate biodiversity data have transformed plant science research, mainly in the past two decades. In this sense, researchers today are overwhelmed by the many different datasets in online repositories. There are also several challenges involved in using these data for biogeographical analyses. Analyses performed on the data available in the repositories show that 70-75% of the total amount of data have spatial deficiencies and a high number of records lack coordinates. This shortage of reliable primary biogeographical information creates serious impediments for biogeographical analyses and conservation assessments and taxonomic revisions consequently produces obstacles for evaluations of threats to biodiversity at global, regional and local levels. With the aim of contributing to botanical and biogeographical research, this paper provides georeferenced spatial data for angiosperm species endemic to Brazil. The information from two reliable online databases, i.e. the Flora do Brasil 2020 floristic database (BFG) and Plantas do Brasil: Resgate Histórico e Herbário Virtual para o Conhecimento e Conservação da Flora Brasileira (REFLORA), which are both based on records collected over the course of the last two centuries, is used to create this spatial dataset. NEW INFORMATION: We provide three taxonomically-edited and georeferenced datasets for basal angiosperms, monocots and eudicots, covering a total of 14,992 endemic species from Brazil. Producing this consolidated dataset involved several months of detailed revision of coordinates and nomenclaturally updating of the names in these datasets. The information provided in this geo-referenced dataset, covering two centuries of specimen collections, will contribute to several botanical and mainly biogeographical studies.

8.
PhytoKeys ; 165: 115-126, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33192150

RESUMEN

Thinouia is a Neotropical genus of lianas with approximately 12 species and is the only genus in tribe Paullinieae with actinomorphic flowers. During a taxonomic revision of the genus and fieldwork in south-western Amazonia, we found a new species that appears similar to Thinouia trifoliata (ex Allosanthus) because of its racemiform inflorescence. However, before describing the new species, we had to confirm that Allosanthus was congeneric with Thinouia so we could place the new species in the correct genus. The results of the phylogenetic analysis, based on molecular data (trnL intron and ITS sequences), show that Allosanthus should be included in Thinouia. Thus, the new taxon is described here as Thinouia cazumbensis sp. nov. The new species is described, illustrated and phylogenetic trees showing relationships within supertribe Paulliniodae and Thinouia and the congeneric Allosanthus are given.

9.
Ecol Evol ; 10(11): 4562-4569, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32551043

RESUMEN

Pseudolaelia is a genus endemic to the eastern Brazilian Atlantic Forest, consisting of 12 accepted species. Some Pseudolaelia species, such as P. vellozicola, P. aguadocensis, P. oliveirana, and P. regentii, referred to here as the PV complex, present extensive intra- and interpopulation morphological polymorphism, raising uncertainty regarding their circumscriptions. Although previous morphological analyses were used to solve the generic boundaries in the PV complex, persuasive genetic evidence is lacking. In order to test the hypothesis that the group under investigation contains only one taxon, amplification profiles of five intersimple sequence repeat (ISSR) markers were used to evaluate genetic diversity, genetic structure, and the relationships among the PV complex species. A total of 134 reproductive individuals were sampled in eight insular populations. Intrapopulation genetic analysis indicated low levels of genetic diversity. Analysis of genetic structure revealed that each of the eight sample locations can be considered unique biological populations as they are highly differentiated from each other. The Mantel test showed a high and positive correlation between genetic and geographic distance (r = .841, p < .002), indicating isolation by distance. The results are consistent with that expected for plants with insular geographical distribution. When testing for the null hypothesis, the low levels of genetic variation among species (F CT = 0.155) suggest that the populations constitute only one highly polymorphic species with a wide distribution.

10.
Biodivers Data J ; 8: e53135, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32617070

RESUMEN

BACKGROUND: Isolated monoliths of granitic and/or gneissic rock rising abruptly from the surrounding landscape are known as inselbergs. Dome-shaped inselbergs are common throughout the Atlantic Forest in south-eastern Brazil, a region known as Sugarloaf Land (SLL). This study aimed to create the first checklist of vascular plant species occurring on lowland inselbergs in SLL, with a focus on vegetation islands. We used information from online databases, our own field sampling and data from previously-published studies. We found 548 vascular plant species (505 angiosperms; 43 ferns and lycophytes) belonging to 69 families and 212 genera. Of all identified species, 536 are native and 12 are naturalised. NEW INFORMATION: We updated the information currently available in Flora do Brasil 2020, as 59% of the angiosperms and 63% of the ferns and lycophytes on our checklist were not previously characterised as occurring on rock outcrops. As a first step towards generating a Virtual Herbarium of lowland inselberg vascular plants, we added barcode vouchers with images available online for 75% of the total number of vascular species. In the official lists of endangered species, 115 angiosperms and five ferns and lycophytes are mentioned. However, the conservation status of many species have not yet been evaluated (77% angiosperms; 88% ferns and lycophytes), thus this list is an important step towards their conservation. The information provided herein is essential for management programmes related to rock outcrops in Brazil as they are facing serious threats to conservation.

11.
Biodivers Data J ; 7: e38248, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31619939

RESUMEN

BACKGROUND: This article provides a quantitative description of flora specimens stored in the Jardim Botânico of Rio de Janeiro Herbarium that belongs to the Federal Conservation Units of Caatinga's phytogeography domain. The Caatinga represents 11% of Brazilian territory and is, in South America, the largest and most biodiverse semi-arid tropical ecoregion, yet only 5% of its territory is covered by Federal Conservation Units, with few collections of flora samples. Thus, providing a georeferenced inventory of existing collections is essential for purposes of species distribution, environmental management and conservation. The aim of this data paper is to gauge, by means of geographic coordinates correction and retrieval of the flora specimens present in the RB Herbarium, the amount of specimen gatherings performed in the Federal Conservation Units belonging to the Caatinga domain. NEW INFORMATION: Currently, the RB data is publicly available online at several biodiversity portals, such as our institutional database JABOT, the Reflora Virtual Herbarium, the SiBBr and the GBIF portal (Lanna et al. 2019). However, a description of the dataset that belongs to the Federal Conservation Units of Caatinga's phytogeography domain as a whole is not yet available in the literature.

12.
PhytoKeys ; (78): 59-81, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28781552

RESUMEN

A synopsis for the genus Commelina in the state of Rio de Janeiro, Brazil, is presented here, including a new species, ten new synonyms, five designated lectotypes, two designated epitypes and an excluded name. Commelina huntii, a new species, is remarkable due to the combination of rusty to rusty-brown hairs at the margin of its leaf-sheaths, connate spathes, white flowers with auriculate medial petal, ovaries with sparse black papillae and dehiscent fruits. Additionally, we provide an identification key, illustrations, and conservation status for the species of Commelina recorded in the state of Rio de Janeiro.

13.
Ecol Evol ; 7(13): 4704-4716, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28690800

RESUMEN

Here, we explore the historical and contemporaneous patterns of connectivity among Encholirium horridum populations located on granitic inselbergs in an Ocbil landscape within the Brazilian Atlantic Forest, using both nuclear and chloroplast microsatellite markers. Beyond to assess the E. horridum population genetic structure, we built species distribution models across four periods (current conditions, mid-Holocene, Last Glacial Maximum [LGM], and Last Interglacial) and inferred putative dispersal corridors using a least-cost path analysis to elucidate biogeographic patterns. Overall, high and significant genetic divergence was estimated among populations for both nuclear and plastid DNA (ΦST(n) = 0.463 and ΦST(plastid) = 0.961, respectively, p < .001). For nuclear genome, almost total absence of genetic admixture among populations and very low migration rates were evident, corroborating with the very low estimates of immigration and emigration rates observed among E. horridum populations. Based on the cpDNA results, putative dispersal routes in Sugar Loaf Land across cycles of climatic fluctuations in the Quaternary period revealed that the populations' connectivity changed little during those events. Genetic analyses highlighted the low genetic connectivity and long-term persistence of populations, and the founder effect and genetic drift seemed to have been very important processes that shaped the current diversity and genetic structure observed in both genomes. The genetic singularity of each population clearly shows the need for in situ conservation of all of them.

14.
PhytoKeys ; (58): 65-79, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26884706

RESUMEN

Knowledge of the geographic distribution of plants is essential to underpin the understanding of global biodiversity patterns. Vascular epiphytes are important components of diversity and functionality of Neotropical forests but, unlike their terrestrial counterparts, they are under-represented in large-scale diversity and biogeographic analyses. This is the case for the Atlantic Forest - one of the most diverse and threatened biomes worldwide. We provide the first comprehensive species list of Atlantic Forest vascular epiphytes; their endemism patterns and threatened species occurrence have also been analyzed. A list with 2,256 species of (hemi-)epiphytes - distributed in 240 genera and 33 families - is presented based on the updated Brazilian Flora Checklist. This represents more than 15% of the total vascular plant richness in the Atlantic Forest. Moreover, 256 species are included on the Brazilian Red List. More than 93% of the overall richness is concentrated in ten families, with 73% represented by Orchidaceae and Bromeliaceae species alone. A total of 78% of epiphytic species are endemic to the Atlantic Forest, in contrast to overall vascular plant endemism in this biome estimated at 57%. Among the non-endemics, 13% of epiphytic species also occur either in the Amazon or in the Cerrado - the other two largest biomes of Brazil - and only 8% are found in two or more Brazilian biomes. This pattern of endemism, in addition to available dated phylogenies of some genera, indicate the dominance of recent radiations of epiphytic groups in the Atlantic Forest, showing that the majority of divergences dating from the Pliocene onwards are similar to those that were recently reported for other Neotropical plants.

15.
Appl Plant Sci ; 1(4)2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25202537

RESUMEN

PREMISE OF THE STUDY: We developed a set of primers for Encholirium horridum, a species closely associated with inselbergs of the Atlantic Forest, to assess genetic diversity, genetic structure, and gene flow between populations of this species. • METHODS AND RESULTS: From an enriched genomic library, 10 primer pairs for polymorphic microsatellite regions were developed. The average number of alleles ranged from eight to 20, and the observed and expected heterozygosities ranged from 0.000 to 1.000, and from 0.000 to 0.929, respectively, across the populations. • CONCLUSIONS: These markers will be useful in evaluating genetic diversity, spatial genetic structure, analysis of gene flow by paternity, and characterization of mating system of E. horridum.

16.
Biota neotrop. (Online, Ed. port.) ; 9(4): 131-148, Oct.-Dec. 2009. ilus, tab, mapas, graf
Artículo en Portugués | LILACS | ID: lil-543230

RESUMEN

A Toca dos Urubus localiza-se no município de Baependi, sul de Minas Gerais, e faz parte da região do Alto Rio Grande. Sua cobertura vegetal compreende um mosaico formado por cerrado, campo rupestre e floresta estacional semidecidual. Foi realizado um levantamento florístico, restrito às espécies vasculares, e uma descrição das três fisionomias encontradas na área. Foram registradas 403 espécies (395 angiospermas e 8 pteridófitas) distribuídas em 77 famílias e 260 gêneros. As famílias mais ricas em número de espécies foram Asteraceae (66 spp.), Poaceae (52 spp.), Fabaceae (32 spp.), Cyperaceae (19 spp.), Melastomataceae e Rubiaceae (16 spp.). O cerrado apresentou o maior número de espécies (322 spp.), seguido pelo campo rupestre (247 spp.) e pelo fragmento de floresta estacional (71 spp.). Apesar da pequena área abordada no presente estudo, aproximadamente 25 ha, uma grande riqueza de espécies foi encontrada, dentre estas 10 são citadas na Lista Vermelha das Espécies Ameaçadas de Extinção da Flora de Minas Gerais, o que reforça ainda mais a necessidade de conservação dessa região.


Toca dos Urubus is located in Baependi municipality, Minas Gerais State, and belong the Alto Rio Grande region. The vegetation comprised a mosaic with cerrado, rocky grassland and seasonally dry tropical forest. A floristic survey was undertaking, restrict to vascular plants, and a descriptive characterization of vegetation is presented. A total of 403 species distributed in 260 genus and 77 families were sampled. Angiosperms comprised 395 species, while pteridophytes comprised eight species. The richest families were Asteraceae (66 spp.), Poaceae (52 spp.), Fabaceae (32 spp.), Cyperaceae (19 spp.), Melastomataceae and Rubiaceae (16 spp.). Most of the species (322 spp.) occur on cerrado, while 247 occur on rocky grassland, and 71 species on seasonally dry tropical forest. Despite the small area studied, approximately 25 ha, high species diversity was found, and 10 of these are included at the Red List of Minas Gerais, strengthening the need for conservation planning within the region.

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