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To investigate how plant-pollinator ecological interactions are affected by habitat modification, and to provide information to support restoration efforts, we characterized trophic interaction networks between bees and plants in a natural regeneration area and forest edge environments in a post-bauxite mining area in the eastern Amazon. For this purpose, bees were collected on the flowers of Gouania cornifolia Reissek (Rhamnaceae), an ordinary native liana in the studied areas, which plays a crucial role in post-mining regeneration by enhancing ecosystem interaction networks between plants and pollinators, and attracting a diversity of floral visitors. The pollen deposited on the bees’ bodies was removed, and through palynology, the plant species that bees visited to collect food were identified. Subsequently, a presence-absence matrix was constructed, trophic interaction networks were created, and metrics analyses were performed. Forest edge areas showed greater native bee diversity, a higher richness of pollen types, and a more nested interaction network with the exclusion of the exotic species Apis mellifera compared to natural regeneration areas. Apis mellifera exploited a greater richness of floral sources due to its wide foraging range, which allowed for movement between different environments, including preserved forest, forest edge, and natural regeneration. This exotic bee alters the structure of interaction networks, being more evident in areas of natural regeneration. We found that bee-plant networks at forest edges demonstrated greater resilience compared to those in natural regeneration areas, emphasizing the importance of preserved forest environments in the recovery of ecological networks. [ABSTRACT FROM AUTHOR]

Stingless bees (Meliponini) are expected to play a central role in structuring mutualistic networks in the Neotropics, as they are generalist and often abundant pollinators. Living in populous social colonies with a perennial life cycle, they require continuous large amounts of resources and often forage on abundant flowerings such as mass‐flowering throughout the year.In this field research, we seek to understand how temporal variations on foraging activity of stingless bees and abundance of mass‐flowering partner plants affect the topology of the plant–pollinator mutualistic networks. The networks were compared between spring and summer, periods of high and low abundances of flowerings and mass‐flowering, respectively.Bees were sampled on flowers, in replicates of floodplain fields in Atlantic Forest of southern Brazil. Interactions with partner plants were considered effective only when bees had pollen on their bodies (potential pollinators). Through analysis of pollen grains attached to their bodies, several topological metrics of networks and functional categories were obtained. The robustness or networks resistance to secondary species loss due to simulated focal species extinction was also measured.The networks maintained similar general structure throughout the year (high nestedness, moderate modularity and connectance, low community‐level specialisation and negative dependency asymmetry). Particularly, nestedness and dependency asymmetry did not change between the two seasons. Community‐level specialisation was higher in summer, contrary to expectations, when there was a collapse in the supply of floral resources and also a reduction in the abundance and foraging pressure of stingless bees. As there was also a greater number of specialist pollinators in summer, the hypothesis of temporal displacement due to foraging pressure from generalists was proposed. At the same time, stingless bees oscillated between network hubs in spring and connectors in summer, reflecting the variation in their abundance between these two seasons. In spring, the greater concentration of foraging by these generalists in the abundant mass‐flowering probably attenuated their diffuse competitive pressure on all other pollinators, even though the foraging overlap was higher in this period. In this period of high abundance of floral resources, specialist pollinators capable of expanding the realised niche are active.Based on recent theoretical conclusions of dynamic model of mutualistic networks structure that incorporated effects of inter‐specific competition and adaptive foraging, we argue that the adaptive foraging of generalist and abundant stingless bees contributes in an important way to the high nestedness and robustness of networks, which ultimately favour the coexistence of species in the long term. Particularly, taking the high intra‐annual turnover of bee and plant species between the two seasons, and the similar floral constancy of both generalist stingless bees and specialist pollinators, we also infer that stingless bees act as generalised pollinators in the networks rewiring throughout the year. [ABSTRACT FROM AUTHOR]

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We describe the nesting biology of Centris (Paracentris) burgdorfi, a solitary bee that nests in sandstone in northeastern Brazil. The nest consists of a shallow tunnel with access to the brood cells. Females of C. burgdorfi made 1–7 brood cells per nest with each cell requiring 2.58 ± 0.40 ( X ¯ ± SD) days to construct. The average cell-building construction time was longer when compared to other Centris species. Females were larger than males, and this difference was reflected in the size of their respective emergence cells. The temperature within C. burgdorfi nests was lower when compared to ambient temperature. Our study is the first to report the nesting biology of C. burgdorfi. The detailed behavior of the female inside the nest was also described, which is unusual in the study of solitary bee nesting biology. [ABSTRACT FROM AUTHOR]

We conducted several tests on the stingless bee Melipona quadrifasciata aiming to determine the impact of the glue used for applying radio frequency identification (RFID) tags on this bee species. The study was organized in three experimental sets, in which we evaluated the effects of a synthetic glue, a natural glue (shellac), and the effects of the bee manipulation alone (control group). We performed (i) an in vitro experiment (bioassay), in which we tested five different experimental treatments in triplicate: chip plus synthetic glue, chip plus shellac, synthetic glue, shellac, and control, totaling 150 bees (n = 30 per treatment); (ii) field experiments, in which we tested the RFID tracking system composed of RFID tags, reading units, antennas, and circuit boards; and (iii) the morphological and histochemical analyses of the flight muscles of bees collected from each experimental treatment (n = 5 per treatment) at 48 h after the beginning of bioassay. Use of the natural glue, as opposed to the synthetic glue, promoted an increase of the bees' longevity while inhibiting detrimental impacts on their foraging activities, as observed by both the bioassay and field experiments. We found negative responses to the synthetic glue treatment combined with the electronic tags, showing that the natural glue induces less morphological damage to the flight muscles of tagged stingless bees. [ABSTRACT FROM AUTHOR]

Context: Human disturbances are one of the main reasons for the recent deficit of pollinators, which can cause severe habitat loss, decreasing food availability and nesting resources for pollinators. However, few studies show how landscapes composition and configuration can impact the pollen foraging of bees. Objectives: We aimed to evaluate how landscape structure and local characteristics can influence the pollen foraging patterns of the stingless bee Melipona quadrifasciata anthidioides in agricultural landscapes of Chapada Diamantina, a region of the Bahia state in Brazil. Methods: Pollen samples were collected from fourteen M. quadrifasciata anthidioides colonies to evaluate how pollen collection varies according to different proportions of human land-use, landscape heterogeneity, plant richness and distance from crops. To explain the richness and diversity of pollen collected by bees, we used generalized linear models, and linear models, compared through the Akaike information criteria corrected for small samples (AICc). Results: Pollen richness can be explained by the distance from crops, plant richness and human land-use proportion. Bees will collect pollen from more plant species when they are in a natural and diverse landscape. Conclusions: Pollinator friendly crop areas must be planned to be surrounded by diverse natural nearby environments, guaranteeing yearlong pollen resources available for bees' maintenance. [ABSTRACT FROM AUTHOR]

Centris species collect floral oil and use this resource in larval food and for waterproofing their cells. We investigated the trophic niche of three distinct populations of Centris burgdorfi, a widely distributed bee in Brazil, by using pollen collected from female bees. Our goal was to determine whether there is versatility regarding sources of oil, nectar, and pollen in different regions of Brazil. By using the pollen, we also determined whether the source of oil used corresponded to the collection apparatus of the females. In total, we sampled 150 C. burgdorfi females and their associated pollen in three distinct habitat types across Brazil. We prepared pollen by acetolysis and performed quantitative analysis on 400 grains per bee. We identified 41 plant species belonging to 18 families that were used by C. burgdorfi. Although none of the plant species used by C. burgdorfi were shared among areas, the Chamaecrista genus was present in the diet at all three sites. The probable oil source came from plants of the genus Krameria, a genus with epithelial elaiophores. In regions where the Krameriaceae family was not present (e.g., southern Brazil), bees used Angelonia integerrima, a plant with trichomate elaiophores, demonstrating that C. burgdorfis exhibited versatility in its dietary breadth among the studied regions. C. burgdorfi proved to be locally specialized in oil floral source and selectivity in pollen sources, but a generalist when evaluated the wide geographic distribution. [ABSTRACT FROM AUTHOR]

The article discusses a study that investigated plants used by the Centris tarsata bee species for its larval food supply in southern Brazil and determined if the bee is polylectic or oligolectic in the region. The study was conducted from March 2002 to December 2003 in the Parque Municipal das Araucárias, Guarapuava (PR) in southern Brazil. It was found that the Solanaceae plant family was visited most often, and that two members of the family were the primary pollen sources for the bees in the study area. The selective behavior of females of the bee species suggests that the bees are oligolectic in their larval provisioning.

Sterols are essential molecules in the membrane lipid composition and precursors of important sterol hormones that regulate many developmental processes. Insects are unable to synthesize sterols de novo and, thus, all phytophagous insects depend on an exogenous source of sterols for growth, development, and reproduction. The sterol requirements of social bees are not fully known due to the fact that there is no well-defined diet available throughout the year with regard to floral resources. Our study aimed to characterize the sterols present in pollen stored in Melipona marginata and Melipona scutellaris colonies, as well as evaluating their presence in the mandibular, hypopharyngeal, and cephalic salivary gland secretions. We analyzed the chemical composition of pollen stored in the colonies and the composition of the cephalic glands of workers in three adult functional phases (newly emerged, nurses, and foragers) by gas chromatography and mass spectrometry. The results showed that the pollen analyzed contained campesterol, stigmasterol, sitosterol, isofucosterol, lanosterol, and small amounts of cholesterol. The glands showed the same compounds found in the pollen analyzed, except lanosterol that was not found in M. scutellaris glands. Surprisingly, cholesterol was found in some glands with relative ratios greater than those found in pollen. [ABSTRACT FROM AUTHOR]

Aiming at promoting interaction among researchers and the integration of data from their pollen collections, herbaria and bee collections, RCPol was created in 2013. In order to structure RCPol work, researchers and collaborators have organized information on Palynology and trophic interactions between bees and plants. During the project development, different computing tools were developed and provided on RCPol website (http://rcpol.org.br), including: interactive keys with multiple inputs for species identification (http://chaves.rcpol.org.br); a glossary of palinology related terms (http://chaves.rcpol.org.br/profile/glossary/eco); a plant-bee interactions database (http://chaves.rcpol.org.br/interactions); and a data quality tool (http://chaves.rcpol.org.br/admin/data-quality). Those tools were developed in partnership with researchers and collaborators from Escola Politécnica (USP) and other Brazilian and foreign institutions that act on palynology, floral biology, pollination, plant taxonomy, ecology, and trophic interactions. The interactive keys are organized in four branches: palynoecology, paleopalynology, palynotaxonomy and spores. These information are collaboratively digitized and managed using standardized Google Spreadsheets. All the information are assessed by a data quality assurance tool (based on the conceptual framework of TDWG Biodiversity Data Quality Interest Group Veiga et al. 2017) and curated by palynology experts. In total, it has published 1,774 specimens records, 1,488 species records (automatically generated by merging specimens records with the same scientific name), 656 interactions records, 370 glossary terms records and 15 institutions records, all of them translated from the original language (usually Portuguese or English) to Portuguese, English and Spanish. During the project's first three years, 106 partners, among researchers and collaborators from 28 institutions from Brazil and abroad, actively participated on the project. An important part of the project's activities involved training researchers and students on palynology, data digitization and on the use of the system. Until now six training courses have reached 192 people. [ABSTRACT FROM AUTHOR]

The Online Pollen Catalogs Network (RCPol) (http://rcpol.org.br) was conceived to promote interaction among researchers and the integration of data from pollen collections, herbaria and bee collections. In order to structure RCPol work, researchers and collaborators have organized information on Palynology in four branches: palynoecology, paleopalynology, palynotaxonomy and spores. This information is collaboratively digitized and managed using standardized Google Spreadsheets. These datasets are assessed by the RCPol palynology experts and when a dataset is compliant with the RCPol data quality policy, it is published to http://chaves.rcpol.org.br. Data quality assessment used to be performed manually by the experts and was timeconsuming and inconsistent in detecting data quality problemas such as incomplete and inconsistent information. In order to support data quality assessment in a more automated and effective way, we are developing a data quality tool which implements a series of mechanisms to measure, validate and improve completeness, consistency, conformity, accessibility and uniqueness of data, prior to a manual expert assessment. The system was designed according to the conceptual framework proposed by Task Group 1 of the Biodiversity Data Quality Interest Group Veiga et al. 2017. For each sheet in the Google Spreadsheet, the system generates a set of assertions of measures, validations and amendments for the records (rows) and datasets (sheets), according to a profile defined for RCPol. The profile follows the policies of data quality measurement, validation and enhancement. The data quality measurement policy encompassess the dimensions of completeness, consistency, conformity, accessibility and uniqueness. RCPol uses a quality assurance approach: only data that are compliant with all the quality requirements are published in the system. Therefore, its data quality validation policy only considers datasets with 100% completeness, consistency, conformity, accessibility and uniqueness. In order to improve the quality in each relevant dimension, a set of enhancements was defined in the data quality enhancement policy. Based on this RCPol profile, the system is able to generate reports that contain measures, validations and amendments assertions with the method and tool used to generate the assertion. This web-based system can be tested at h ttp://chaves.rcpol.org.br/admin/data-quality with the dataset https://docs.google.com/spreadsheets/u/1/d/1gH0aa2qqnAgfAixGom3Gnx6Qp 91ZvWhUHPb_QeoIreQ. This system is able to assure that only data compliant with the data quality profile defined by RCPol are fit for use and can be published. This system contributes significantly to decreasing the workload of the experts. Some data may still contain values that cannot be easily automatically assessed, e.g. validate if the content of an image matches the respective scientific name, so expert manual assessment remains necessary. After the system reports that data are compliant with the profile, a manual assessment must be performed by the experts, using the data quality report as support, and only after that will the data be published. The next steps include archival of the data quality reports in a database, improving the web interface to enable searching and sorting of assertions, and to provide a machine readable interface for the data quality reports. [ABSTRACT FROM AUTHOR]