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1.
The 24 000+ described species of Vespoidea include many well-known stinging wasps, such as paper wasps and hornets (Vespidae), velvet ants (Mutillidae), spider wasps (Pompilidae) and ants (Formicidae). The compelling behaviours of vespoids have been instrumental in developing theories of stepwise evolutionary transitions, which necessarily depend on an understanding of phylogeny, yet, existing morphological phylogenies for Vespoidea conflict. We collected molecular data from four nuclear genes (elongation factor-1α F2 copy, long-wavelength rhodopsin, wingless and the D2–D3 regions of 28S ribosomal RNA (2700 bp in total)) to produce the first molecular phylogeny of Vespoidea. We analysed molecular data alone and in combination with published morphological data from Brothers and Carpenter. Parsimony analyses left many deeper nodes unsupported, but suggested paraphyly of three families. Total-evidence Bayesian inference produced a more resolved tree, in which the monophyly of Vespoidea was nevertheless ambiguous. Bayesian inference of molecular data alone returned a well-resolved consensus with posterior probabilities of over 95% for most nodes. We used this topology as the best estimate of phylogeny at the family and subfamily levels. Notable departures from previous estimates include: (i) paraphyly of Vespoidea resulting from the nesting of Apoidea within a lineage comprising Formicidae, Scoliidae and two subfamilies of Bradynobaenidae; (ii) paraphyly of Bradynobaenidae, Mutillidae and Tiphiidae; (iii) a sister relationship between Rhopalosomatidae and Vespidae; and (iv) Rhopalosomatidae + Vespidae as sister to all other vespoids/apoids. We discuss character evidence in light of the new phylogeny, and propose a new classification of Aculeata that recognizes eight superfamilies: Apoidea, Chrysidoidea, Formicoidea, Pompiloidea, Scolioidea, Tiphioidea, Thynnoidea and Vespoidea.  相似文献   

2.
The relationship between seed germination and ecological niche is determined by matching germination characteristics with environmental features. In this study, we selected tree species occurring in the largest savanna wetland in South America – the Pantanal. Very few species are endemic or exclusively found in savanna wetlands, and the majority of tree species occurring in the Pantanal are also found in the neighbouring Brazilian Cerrado, a drier vegetation type that does not flood. We investigated the relationship between germination characteristics and occurrence of savanna trees in wetlands testing the hypothesis that such seeds are tolerant to flooding. We also addressed the question of whether seed tolerance to flood, assessed by survival analysis, explains tree distribution along a gradient of flooding intensity. In this flooding gradient, widely distributed species are those that occur in areas subjected to low as well as to high flooding intensity whereas restricted distributed species are those that occur only in areas subjected to a low level of flood. Seeds from tree species occurring in areas subjected to different flooding intensities were collected. Seed tolerance and germination during and after both one and two months of simulated flood were evaluated. Our results show that seeds of most of the studied savanna species tolerated submergence, which helps to explain their occurrence and wide distribution in wetlands. Nevertheless, germination behaviour checked by survival functions (i.e. how germination is distributed over time) partially explained tree species distribution along a flooding gradient. We conclude that seed tolerance to flooding is one of the components of the regeneration niche that determines tree occurrence and distribution at the regional scale, from savanna to wetland, but not at a local scale along a flooding gradient.  相似文献   

3.
1. Dung beetles perform relevant ecological functions in pastures, such as dung removal and parasite control. Livestock farming is the main economic activity in the Brazilian Pantanal. However, the impact of cattle grazing on the Pantanal's native dung beetle community, and functions performed by them, is still unknown. 2. This study evaluated the effects of cattle activity on dung beetle community attributes (richness, abundance, biomass, composition, and functional group) as well as their ecological functions (dung removal and soil bioturbation) in the Pantanal. In January/February 2016, dung beetles were sampled and their ecological functions measured in 16 sites of native grasslands in Aquidauana, Mato Grosso do Sul, Brazil, 10 areas regularly grazed by cattle and six control ungrazed areas (> 20 years of abandonment). 3. In all, 1169 individuals from 30 species of dung beetles were collected. Although abundance, species richness, and biomass did not differ between grasslands with and without cattle activity, species composition and functional groups differed among systems. Large roller beetles were absent from non‐cattle grasslands, and the abundance, richness, and biomass of medium roller beetles was higher in those systems. 4. Despite causing changes in species/functional group composition, the results of this study show that a density compensation of functional groups in cattle‐grazed natural grasslands seems to have conserved the ecological functions (dung removal and soil bioturbation), with no significant differences between systems. 5. Therefore, these results provide evidence that cattle breeding in natural grasslands of the Brazilian Pantanal can integrate livestock production with the conservation of the dung beetle community and its ecological functions.  相似文献   

4.
Vespoidea are the most functionally diverse superfamily of Hymenoptera. Ecological studies involving this family are primarily based on eusocial groups, including ants and social paper wasps. In the present study, we examine stinging wasp (Vespoidea) faunal diversity in the Atlantic Rain Forest, which is one of the most diverse and threatened ecosystems in the World. Three conservation areas were sampled employing a standardized sample protocol. Families and functional groups of Vespoidea were collected in each area, with the exception ants (Formicidae), and analyzed using diversity analyses, to generate taxonomic diversity and distinctness indices. Results indicated Pompilidae was the most diverse family, and the idiobiont parasitoid type was the most diverse functional group in the three study areas. Núcleo Picinguaba of the Parque Estadual da Serra do Mar was taxonomically and functionally the most diverse and species rich area. Parque Estadual Intervales showed the highest number of dominant species and diversity of koinobiont parasitoids, while the Rebio Sooretama exhibited a decrease in several diversity parameters.  相似文献   

5.
Wetland seed banks comprise the propagules of plant species that have species-specific germination requirements for germination in either flooded or dry conditions. At the community level, wetland structure and succession during and after a seasonal flooding event depends upon the early life-history requirements of species, including germination under flooded and dry conditions. We examined the effects of simulated flood and post-flood scenarios on seedling emergence from a seed bank of seasonally flooded grassland in the Pantanal, Brazil. Field samplings were conducted in both wet and dry seasons, both of which were subject to flood and post-flood conditions. A total of 70 species emerged from the seed bank, dominated by Poaceae and Cyperaceae. Sixteen species were exclusive to the wet and one exclusive to the dry season. The richness of perennial species was higher under flood conditions, while the richness of annuals was greater post-flood. In general, the aquatic and amphibious species exhibited a significant germination response to flooding. Terrestrial species only germinated in post-flood conditions, with higher richness in the dry season. Four species had high seedling abundance in both treatments. The capacity of regeneration by seeds is high in these grasslands and can be increased by seasonal flooding and drawdown. In these seasonally flooded grasslands, we observed three main germination strategies: under flooded conditions, aquatic and amphibious species; post-flood conditions, an explosion of annual amphibious and terrestrial species; and in moist soil, perennial terrestrial species. The differential responses to flooding versus post-flood conditions help to maintain the structure and species richness in the community over time.  相似文献   

6.
The Brazilian Atlantic Forest is a highly threatened biodiversity hotspot that has been the subject of several complementary conservation assessments and priority-setting initiatives in the last 30 years. Results of these initiatives have relied on distinct types of distribution data for biodiversity features and differ in the objectivity and repeatability of their methodologies. Here we refine earlier priority-setting exercises using the key biodiversity areas (KBA) approach. We evaluate how well these KBAs are represented in the existing protected areas system, prioritize among them, and analyze critical aspects of the KBA methodology in the Brazilian Atlantic Forest context, such as its ability to guide specific conservation strategies. Building upon an extensive database with 1,636 species records and 122 previously identified Important Bird Areas, we demonstrate that conservation assessments in highly fragmented landscapes may be benefited by high resolution species data as is required by the KBA process. We identify 538 KBAs for 141 globally threatened vertebrate species. Prioritizing among these KBA, we highlight the 24 most irreplaceable sites for terrestrial vertebrate species conservation in the Atlantic Forest, based on existing data.  相似文献   

7.
A preliminary detective survey for the hymenopteran insect fauna of Jazan Lake dam region, Southwest Saudi Arabia, was carried out for one year from January 2018 to January 2019 using mainly sweep nets and Malaise traps. The survey revealed the presence of three hymenopteran Superfamilies (Apoidea, Vespoidea and Evanioidea) representing 15 species belonging to 10 genera of 6 families (Apidae, Crabronidae, Sphecidae, Vespidae, Mutillidae, and Evaniidae). The largest number of species has belonged to the family Crabronidae is represented by 6 species under 2 genera. While the family Apidae, is represented by 2 species under 2 genera. Family Vespidae is represented by 2 species of one genus. While, the rest of the families Sphecidae, Mutillida, and Evaniidae each is represented by only one species and one genus each. Eleven species are predators, two species are pollinators and two species are parasitics. Note for each family was provided, and species was provided with synonyms and general and taxonomic remarks and their worldwide geographic distribution and information about their economic importance are also included. All species were photographed with dorsal and lateral views.  相似文献   

8.
We studied the occurrence of Pseudoscorpiones in the soil, leaf litter, and in canopies of a monodominant forest of Attalea phalerata at different seasons in the northern region of the Brazilian Pantanal. A total of 1197 pseudoscorpions from nine families and 16 species were sampled. Olpiidae, Chernetidae, and Geogarypidae predominated in soil and leaf litter. Chernetidae was the most abundant family in canopies. Soil and canopy corresponded to distinct habitats in relation to pseudoscorpion abundance and richness, with the canopies being the most diversified environment. These habitats are occupied in different ways by pseudoscorpion populations. Geogarypus sp. occurs in the edaphic environment during receding water and dry season, but can be found in canopies of A. phalerata exclusively during high water. This alternation in the use of the edaphic environments and canopies in the same area by pseudoscorpion species probably happens due to the strong seasonality of the Brazilian Pantanal.  相似文献   

9.
In many parts of the world, replacement of natural grasslands by woody plants has resulted in a decrease of pasture areas and in habitat loss for a variety of animal species, including amphibians. Wetlands are especially susceptible to invasive plants, both native and exotic, but the effects of such invasions on animal assemblages remain poorly understood. Here, we present information on the impact of selected environmental variables, especially coverage by the native shrub Combretum laxum Jacq., on the structure of an anuran assemblage in the Pantanal, a huge flood‐pulsed South American wetland. Anurans were surveyed during the rainy season in 17 plots, which differed in extent of C. laxum coverage, leaf litter volume, soil moisture and distance to permanently wet areas. Effects of these environmental variables on the species number, relative abundance and composition of the anuran assemblage were evaluated using multivariate statistical analyses. We captured 1203 anurans, of 21 species from four families. Both the number of species and the relative abundance of anurans were lower in plots with greater C. laxum coverage, which also influenced anuran species composition. Number of species was highest in plots located closest to permanently wet areas, which provide protection from desiccation and other resources during the Pantanal dry season, and so could be considered source areas of anurans. While many anuran species were negatively affected by the homogenization of the landscape caused by shrub encroachment, some seemed to be favoured in such circumstances. For these, dense shrub encroachment into natural grasslands may provide safer migratory routes to permanently wet habitats. Thus, at the mesoscale, a mosaic of areas with different levels of coverage by C. laxum (shrub islands) may aid anuran assemblages in the Pantanal wetlands, facilitating the maintenance of higher beta and gamma diversity.  相似文献   

10.
Effective management and conservation of an ecosystem requires information on species assemblages as well as reliable estimates of population sizes to plan, implement and evaluate management strategies. The Brazilian Pantanal is one of the world's largest freshwater wetlands and considered a priority landscape for wildlife conservation. It is subject to pluri-annual extreme dry and wet periods, which cause extreme flood and drought events, which strongly affect wildlife. Using the line-transect method, this study examined the distribution of densities and metabolic biomass of medium- to large-sized nonvolant mammals in forest, cerrado and floodplain landscapes, in an area with low anthropogenic influence, in the central area of the Brazilian Pantanal during a prolonged drought. Comparisons with a previous survey conducted during years of average rainfall in part of the study area suggest that population fluctuations of certain species are closely associated with water due to the drought. Results from this study showed that mammal assemblages varied between landscapes. Forested landscapes have the highest densities of mammals and are the most important in terms of relative energy consumption. In addition, at the time of the study, frugivores were found to have higher energy consumption than browser/grazers across the three landscapes; most fruits are produced in forested areas stressing their importance. By converting forested landscapes into grasslands, the intensification of ranching practices seriously threatens biodiversity and ecological processes in the region.  相似文献   

11.
巴西植物遗传资源保护与对外交流管理   总被引:1,自引:1,他引:0  
巴西拥有高等植物55000种,居世界第一。植被分为6个区系,即亚马逊雨林、塞拉多(Cerrado)稀树草原、卡廷加(Caatinga)旱生植被、大西洋雨林、南方森林草原和潘塔纳尔(Pantanal)湿地植被。已建立554个原生境保护区和126个基因库,保存植物遗传资源25万份。对外交流由巴西农业科学院(EMBRAPA)遗传资源与生物技术中心(CENARGEN)统一管理。  相似文献   

12.
Conservation efforts are often aimed at one or a few species. However, habitat sustainability relies on ecological interactions among species, such as seed dispersal. Thus, a community-scale conservation strategy may be more valuable in some settings. We describe communities of primary (primates) and secondary (dung beetles) seed dispersers from 5 sites in the Brazilian Amazon. We estimate community biomass of these taxa and, using multivariate ordination, examine the potential for natural reforestation at each site, given the communities of seed dispersers present. Since disturbed habitat is increasingly common and increasingly the focus of conservation efforts, we also examine differences among seed disperser communities between primary forest and secondary growth at each site. Analyses of faunal biomass in different localities and habitats indicate that secondary growth receives nearly as much use by primates as primary forest; given the dominant groups of dung beetles in secondary growth, disturbed habitat should show a pattern of seed burial that is clumped and deep. Areas with high biomass of Alouatta spp. and the large nocturnal dung beetle species may have the greatest potential for natural reforestation of secondary growth particularly for large seeded species. The data suggest that knowledge of the biomass of primary and secondary dispersing fauna facilitates predictions for the likelihood of disturbed habitat to regenerate and comparisons of sites in broader geographical areas e.g., Neotropical vs. Paleotropical forests.  相似文献   

13.
Through their excavations, giant armadillos (Priodontes maximus) alter their physical surroundings and create new habitats, which influence resources for at least 24 other species of vertebrates in the Brazilian Pantanal. The role of this poorly known species as an ecosystem engineer may be of high value to the community of vertebrates.  相似文献   

14.
Understanding and predicting vegetation patterns in floodplains are essential for conservation and/or restoration of river floodplains subject to hydrological alterations. We propose a conceptual hydroecological model to explain the disturbance mechanisms driving species diversity across large river floodplains. These ecosystems harbor a unique set of flood-tolerant species different from the surrounding upland vegetation. In elevation gradients across pristine floodplains, the greater the flooding, the fewer the number of plant species. As terrain elevation increases, flood depth and duration decrease and it is more likely that species composition is influenced by external natural or human-driven disturbances. The spatial interaction between the natural flood regime and upland factors creates patterns of disturbance gradients that influence how floodplain vegetation establishes. In regions where upland conditions are subject to strong external disturbances, species diversity peaks at intermediate stages along the disturbance gradient. We demonstrate this concept with observations from the Central Amazon and Pantanal in Brazil, the Mekong’s Tonle Sap in Cambodia, and the Okavango Delta in Botswana. We discuss how this model could be further elaborated and validated to inform management of large river basins under the impact of upstream-induced flood pulse alterations.  相似文献   

15.
The pollen diet of Africanized honeybees Apis mellifera L. was studied during seven months (October 2006 to April 2007) in a natural forest fragment in the southern Pantanal, sub-region of Abobral, Mato Grosso do Sul. The analysis of the pollen diet was based on direct observations of the bees visiting flowers as well as through the use of a pollen trap installed in a wild colony in a tree hole in the same forest fragment. The total of 28 species in 15 botanical families were observed as potential sources of pollen for A. mellifera, with visits registered in 24 of these species in 13 botanical families. In the pollen trap we recorded 25 pollen types. This study is the first report to use this type of trap for pollen collection in the Neotropical region and aimed to identify the polliniferous bee plants of Brazilian Pantanal.  相似文献   

16.
We studied the species richness and composition of frogs in 10 restinga habitats (sand dune environments dominated by herbaceous and shrubby vegetation) along approximately 1500 km of coastal areas of three Brazilian States: Rio de Janeiro (Grumari, Maricá, Massambaba, Jurubatiba and Grussaí), Espírito Santo (Praia das Neves and Setiba) and Bahia (Prado and Trancoso). We estimated beta-diversity and similarity among areas and related these parameters to geographic distance between areas. All areas were surveyed with a similar sampling procedure. We found 28 frog species belonging to the families Hylidae, Microhylidae, Leptodactylidae and Bufonidae. Frogs in restingas were in general nocturnal with no strictly diurnal species. The richest restinga was Praia das Neves (13 species), followed by Grussaí and Trancoso (eight species in each). The commonest species in the restingas was Scinax alter (found in eight restingas), followed by Aparasphenodon brunoi (seven areas). Our data shows that richness and composition of frog communities vary consistently along the eastern Brazilian coast and, in part, the rate of species turnover is affected by the distance among areas. Geographic distance explained approximately 12% of species turnover in restingas and about 9.5% of similarity among frog assemblages. Although geographic distance somewhat affects frog assemblages, other factors (e.g. historical factors, disturbances) seem to be also involved in explaining present frog assemblage composition in each area and species turnover among areas. The frog fauna along restinga habitats was significantly nested (matrix community temperature = 26.13 degrees; p = 0.007). Our data also showed that the most hospitable restinga was Praia das Neves and indicated that this area should be protected as a conservation unit. Frog assemblage of each area seems to partially represent a nested subset of the original assemblage, although we should not ignore the importance of historical factors. This nestedness pattern, in part, probably results from the intensive fragmentation of restinga habitats. Possibly, many frog species may have been lost in some studied areas as a result of the extensive habitat degradation to which restinga habitats are presently exposed.  相似文献   

17.
The wetlands of the Brazilian Pantanal host large concentrations of diverse wildlife species and hematophagous arthropods, conditions that favor the circulation of zoonotic arboviruses. A recent study from the Nhecolândia sub-region of Pantanal reported serological evidence of various flaviviruses, including West Nile virus and Ilheus virus (ILHV). According to the age of seropositive horses, at least three flaviviruses, including ILHV, circulated in the Brazilian Pantanal between 2005 and 2009. To extend this study, we collected 3,234 adult mosquitoes of 16 species during 2009 and 2010 in the same sub-region. Mosquito pool homogenates were assayed for infectious virus on C6/36 and Vero cell monolayers and also tested for flaviviral RNA by a group-specific real-time RT-PCR. One pool containing 50 non-engorged female specimens of Aedes scapularis tested positive for ILHV by culture and for ILHV RNA by real-time RT-PCR, indicating a minimum infection rate of 2.5 per 1000. Full-length genomic sequence exhibited 95% identity to the only full genome sequence available for ILHV. The present data confirm the circulation of ILHV in the Brazilian Pantanal.  相似文献   

18.
The Brazilian biomes (Amazon, Atlantic Forest, Cerrado, Caatinga, Pantanal, and Pampa) comprise one of the highest levels of plant diversity in the world; however, non-sustainable practices, deforestation, and land use have resulted in significant losses and fragmentation of the native forests. These ecosystems are now threatened and protection of their native plants through ex situ conservation is an urgent necessity. Cryopreservation and in vitro conservation are complementary options for securing and protecting Brazil’s native plant species because their potential economic value is critically important to develop strategies that will (1) support their sustainable utilization, (2) protect against the over-exploitation of species growing in natural habitats, and (3) conserve the genetic diversity of germplasm from species of different provenances. Biotechnological approaches will help to address future economic and environmental demands placed upon already at-risk species. Conserving seed germplasm ex situ provides an additional safeguard against the risks (e.g., loss due to disease, climate change) of field conservation. Moreover, seed banks and cryobanks permit the long-term conservation of a wider genetic base; this offsets the labor and space intensive costs of conserving in the active growing state. This paper is a compilation of the current status of strategies applied for conserving Brazilian native plant species.  相似文献   

19.
This study presents the diversity and distribution of myriapod species associated with different habitats in a seasonally flooded forest composed predominantly of Vochysia divergens Pohl. (Vochysiaceae) in the Brazilian Pantanal. We evaluated species richness distribution across habitats and over different seasonal periods, and also identified possible survival strategies employed during periodic flooding that occur within this forest. A total of 1505 myriapods were sampled, representing four classes and 15 species. Diplopoda and Chilopoda were the most abundant and rich taxa. Pauropoda and Symphyla were represented by only one species each. Species richness was distinctly distributed across habitats evaluated in this forest, as well as over the different seasonal periods. Survival strategies observed in Diplopoda and Chilopoda were primarily associated with vertical migration ranging from the edaphic environment to tree trunks and canopies, and horizontal migration associated with water level before and during the flood period. Species richness was considered low; however, the survival strategies, especially vertical and horizontal migration, demonstrate the adaptation of these species to the seasonal floods of this ecosystem.  相似文献   

20.
Conservation status assessments are one of the key scientific measures to inform solutions aiming at minimizing the biodiversity crisis of the Anthropocene, being the IUCN’s Red List approach the most widely used and accepted tool for species-level assessment. However, Red Lists are time-consuming because they necessarily rely on expert evaluation. Thus, the development of automated tools, able to handle the huge increasingly amount of data in less time, are useful for guiding conservation actions. In this sense, the aim of this research is to evaluate an automated preliminary conservation status assessment for all known endemic flora from the megadiverse Brazil. Vascular taxa were derived from the Brazilian Flora 2020 project and occurrences were retrieved from GBIF and SpeciesLink. Data was filtered and then evaluated with the aid of ConR package and high resolution nationwide vegetation maps. The current approach estimates that 28.78 % (22.72–43.75 %) of the endemic flora is threatened by extinction, with different patterns between the six Brazilian ecoregions: from 30.75 % (Amazonia’s lower) to 100 % (Pantanal’s best/upper). The high variation in the estimate is because more than a fifth of the vascular flora is poorly known (<3 records). Accuracy assessment reveals a good agreement between the reference from the Brazilian Flora 2020 project and a binary classification (threatened/not- or near-threatened), with an overall accuracy of 61.67 % (58.84–64.47 %), but with limited capacity to distinguish between the IUCN’s threat levels (Critically Endangered, Endangered and Vulnerable to extinction). Bromeliaceae and Orchidaceae are the families with higher estimated number, proportion in relation to the whole family and uncertainty of estimated threatened species, reflecting that herb is the life form with far more threatened species, followed by shrubs. The presented approach can serve as rapid assessment tool for optimizing efforts and to identify potentially threatened species and hotspots of species that could be considered for timely and effective conservation actions. As a practical recommendation, botanists could prioritize the assessment of the species indicated here as threatened, as there is a high chance of confirming this status, and efforts can be properly addressed for their conservation. Moreover, the automated approach can be useful for monitoring the progress of conservation targets. Finally, further scientific research is urgent to fill the knowledge gap on the Brazilian flora aiming at its conservation.  相似文献   

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