Melipona Scutellaris Research Articles

Major chemical contituents of geopropolis from Melipona scutellaris

Geopropolis is a different kind of propolis collected by the stingless bee Melipona scutellaris that is made up of plant resins, wax and soil. Its crude extract was cytotoxic to colon cancer cells, however its chemical profile has not been thoroughly studied so far. We used bioguided fractionation against two colon cancer cell lines to purify the major bioactive compounds. We isolated and identified prenylated coumarins, benzophenones and cinnamic acid derivatives from geopropolis. Most of those compounds are found in plants from the genus Kielmeyera (Guttiferae), which is widely distributed in the Northeast Brazil, the area of collection of geopropolis.

Morphology of mandibular and intramandibular glands in workers and virgin queens of Melipona scutellaris

The interactions of insect societies are associated with chemical signals released by the exocrine glands that control some insect behaviors. Exocrine glands can be classified into different classes: class I release substances that cross the body cuticle and class III glands that have a conducting canal. This study compares the morphology of intramandibular and mandibular glands in virgin queens of different ages, as well as in nurses and forager workers of Melipona scutellaris. We have found the occurrence of two types of glands inside the mandible; glands of class I, corresponding to a well-developed epithelium, secretory only in virgin queens, and glands of class III. On the other hand, mandibular glands have been found to be well-developed in workers and queens and they also have high amounts of mitochondria and smooth endoplasmic reticulum. Together, these data show that the mandibular and intramandibular glands of M. scutellaris virgin queens have morphological features that indicate the synthesis of compounds that are lipid in nature. Furthermore, both glands have a similar developmental degree in newly emerged and 7-day-old ones.

Susceptibility of Melipona scutellaris Latreille, 1811 (Hymenoptera: Apidae) worker bees to Beauveria bassiana (Bals.) Vuill.

Entomopathogenic fungi are often used as an alternative method for insect pest control. However, few studies mention the action of these fungi on bees and selectivity to beneficial organisms in agroecosystems. The objective of the present study was to assess the susceptibility of Melipona scutellaris bees to the isolate of the entomopathogenic fungus Beauveria bassiana. The experiment was carried out by applying fungus suspension on the back and by contact on recently emerged bees. A complete randomized design was used with five treatments (four concentrations: 1 x 105, 1 x 106, 1 x 107, 1 x 108 conidia/ml and a control of distilled water) with five replications. The mortality data were subjected to variance analysis, regression Probit analysis Statistic software, obtaining the estimate of the lethal dose to 50% of the population (LD50). The curves adjustment to model was evaluated by Pearson test chi-squared test and differences between the curves evaluated by test of parallelism. The B. bassiana was virulent uruçu bees (M. scutellaris) causing mortality at lower dose. Based on these results, it can make recommendations to minimize the impact, contributing to maintenance of naturalpopulations of these insects.

Communities of Social Bees (Apidae: Meliponini) in Trap-Nests: the Spatial Dynamics of Reproduction in an Area of Atlantic Forest.

As most stingless bee species depend on preexisting cavities, principally tree hollows, nesting site availability may represent an important restriction in the structuring of their forest communities. The present study examined the spatial dynamics of stingless bee communities in an area of Atlantic Forest by evaluating their swarming to trap-nests. The field work was performed in the Michelin Ecological Reserve (MER) on the southeastern coast of the state of Bahia, Brazil. Seven hundred and twenty trap-nests were distributed within two forest habitats in advanced and initial stages of regeneration. The trap-nests were monitored between September 2009 and March 2011. Twenty-five trap-nests were occupied by five bee species, resulting in a capture ratio of 0.035 swarms/trap (approximately 0.14 swarms/ha), corresponding to 10 swarms/year (0.056 swarms/ha/year). According to previous study at MER, the most abundant species in natural nests were also the most common in trap-nests in the two forest habitats examined, with the exception of Melipona scutellaris Latreille. Swarms of higher numbers of species were captured in initial regeneration stage forests than in advanced regeneration stage areas, and differences in species compositions were significant between both habitats (p = 0.03); these apparent differences were not consistent, however, when considering richness (p = 0.14) and total abundance (p = 0.08). The present study suggests the existence of a minimum cavity size threshold of approximately 1L for most local species of stingless bees and sustains the hypothesis of a mass effect of Tetragonisca angustula Latreille populations from surrounding disturbed habitats on the MER forest community in terms of propagule (swarm) pressure. Examining swarm densities with trap-nests can be a promising technique for comparative analyses of the carrying capacities of forest habitats for stingless bee colonies, as long as size thresholds of cavities for nesting are taken into consideration.

Meliponiculture in Quilombola communities of Ipiranga and Gurugi, Paraíba state, Brazil: an ethnoecological approach

BackgroundThe Quilombola communities of Ipiranga and Gurugi, located in Atlantic Rainforest in Southern of Paraíba state, have stories that are interwoven throughout time. The practice of meliponicultura has been carried out for generations in these social groups and provides an elaborate ecological knowledge based on native stingless bees, the melliferous flora and the management techniques used. The traditional knowledge that Quilombola have of stingless bees is of utmost importance for the establishment of conservation strategies for many species.MethodsTo deepen study concerning the ecological knowledge of the beekeepers, the method of participant observation together with structured and semi-structured interviews was used, as well as the collection of entomological and botanical categories of bees and plants mentioned. With the aim of recording the knowledge related to meliponiculture previously exercised by the residents, the method of the oral story was employed.Results and discussionResults show that the informants sampled possess knowledge of twelve categories of stingless bees (Apidae: Meliponini), classified according to morphological, behavioral and ecological characteristics. Their management techniques are represented by the making of traditional cortiço and the melliferous flora is composed of many species predominant in the Atlantic Rainforest. From recording the memories and recollections of the individuals, it was observed that an intricate system of beliefs has permeated the keeping of uruçu bees (Melipona scutellaris) for generations.ConclusionAccording to management techniques used by beekeepers, the keeping of stingless bees in the communities is considered a traditional activity that is embedded within a network of ecological knowledge and beliefs accumulated by generations over time, and is undergoing a process of transformation that provides new meanings to such knowledge, as can be observed in the practices of young people.

Genetic variability and population structure in Melipona scutellaris (Hymenoptera: Apidae) from Bahia, Brazil, based on molecular markers

Melipona scutellaris is an important pollinator in natural and cultured areas from northeastern Brazil. Therefore, the goal of this work was to investigate the genetic diversity and population structure of M. scutellaris within its Bahia range, relating putative geographical influences on population dynamics. A total of 111 colonies from 13 municipalities in Bahia from sea level up to 1,011 m of altitude were sampled. Five species-specific codominant (microsatellites) and ten dominant (ISSR) primers were amplified, yielding from 2 to 13 alleles and 94 bands, respectively. The mean genetic diversity (He) was 0.50 for microsatellites and 0.33 for ISSR markers. AMOVA revealed that most of genetic variation is found within localities (82.6 % for microsatellites and 73.6 % for ISSR), and UPGMA and Bayesian analysis revealed the formation of two genetic groups related to altitude. Therefore, conservation strategies should take altitude variation into consideration to assure the genetic integrity of M. scutellaris.

Sneaky queens in Melipona bees selectively detect and infiltrate queenless colonies

Insect societies are characterized by advanced cooperation, but at the same time the complexity of their colonies renders them susceptible to reproductive parasitism. Recently, a genetic study on the Brazilian stingless bee Melipona scutellaris showed that unrelated queens frequently invade and take over colonies in which the mother queen had died. In the present study, we investigated this phenomenon using radio frequency identification (RFID) tags. We confirmed that alien queen take-overs are common within this species, and demonstrated that mated queens actively seek out colonies without a queen to reproduce in. Furthermore, we found that queens only penetrate their target colonies in the evening, when guarding efficiency is significantly reduced. We hypothesize that this strategy reduces the chance of the queens being attacked by entrance guards, thus maximizing their chance of successful infiltration.

Differences of the Daily Flight Activity Rhythm in two Neotropical Stingless Bees (Hymenoptera, Apidae)

Stingless bees are mainly tropical and subtropical, eusocial bees and perform activities that are both internal and external to the nest. This study aims to investigate and compare the daily flight activities of Melipona scutellaris Latreille and Frieseomelitta doederleini (Friese). The daily flight activities of the two Meliponini species was regular for both initial and final activities and for preferential time of activity throughout the months, which may indicate the presence of a biological rhythm synchronized by the daily light-dark cycle. Temperature, light intensity and relative humidity probably influenced the rhythms of activity during the day, in a way that may act as a modulator of bee rhythms. M. scutellaris was the larger and darker bees and showed earlier activities and in lower temperatures when compared to F. doederleini, which were smaller bees.

Antimicrobial and antiproliferative activities of stingless bee Melipona scutellaris geopropolis

BackgroundGeopropolis is a type of propolis containing resin, wax, and soil, collected by threatened stingless bee species native to tropical countries and used in folk medicine. However, studies concerning the biological activity and chemical composition of geopropolis are scarce. In this study, we evaluated the antimicrobial and antiproliferative activity of the ethanolic extract of geopropolis (EEGP) collected by Melipona scutellaris and its bioactive fraction against important clinical microorganisms as well as their in vitro cytotoxicity and chemical profile.MethodsThe antimicrobial activity of EEGP and fractions was examined by determining their minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against six bacteria strains as well as their ability to inhibit Streptococcus mutans biofilm adherence. Total growth inhibition (TGI) was chosen to assay the antiproliferative activity of EEGP and its bioactive fraction against normal and cancer cell lines. The chemical composition of M. scutellaris geopropolis was identified by reversed-phase high-performance liquid chromatography and gas chromatography–mass spectrometry.ResultsEEGP significantly inhibited the growth of Staphylococcus aureus strains and S. mutans at low concentrations, and its hexane fraction (HF) presented the highest antibacterial activity. Also, both EEGP and HF inhibited S. mutans biofilm adherence (p < 0.05) and showed selectivity against human cancer cell lines, although only HF demonstrated selectivity at low concentrations. The chemical analyses performed suggest the absence of flavonoids and the presence of benzophenones as geopropolis major compounds.ConclusionsThe empirical use of this unique type of geopropolis by folk medicine practitioners was confirmed in the present study, since it showed antimicrobial and antiproliferative potential against the cancer cell lines studied. It is possible that the major compounds found in this type of geopropolis are responsible for its properties.

Genetic variability in Melipona scutellaris from Recôncavo, Bahia, Brazil

Bees play a key role in pollination and thereby help maintain plant diversity. The stingless bee Melipona scutellaris is an important pollinator in northeastern Brazil because it is endemic to this region. Both deforestation and timber harvesting have reduced the nesting sites for this species, thus reducing its population and range. Genetic studies may help reverse this process by providing important tools for their proper management with a view to conservation of this species. Microsatellite markers have proven to be ideal for mapping genes and population genetic studies. Our aim was to study, using microsatellite markers, the interpopulation genetic variability of M. scutellaris in different parts of the Recôncavo region in Bahia State, Brazil. In all, 95 adult workers from 11 localities in Recôncavo Baiano (Amargosa, Cabaceiras do Paraguaçu, Conceição da Feira, Conceição do Almeida, Domingos Macedo Costa, Governador Mangabeira, Jaguaripe, Jiquiriça, Maragojipe, São Felipe, and Vera Cruz) were analyzed using 10 pairs of microsatellite primers developed for different Meliponini species. The total number of alleles, allele richness, and genetic diversity ranged from 2 to 7 per locus (average = 4.4), 1.00 to 4.88, and 0.0 to 0.850, respectively. The expected and observed heterozygosities varied from 0.0 to 0.76 and 0.0 to 0.84, respectively. No locus showed deviation from the expected frequencies in the chi-square test or linkage disequilibrium. The fixation index, analysis of molecular variance, and unweighted pair-group method using the arithmetic average revealed the effects of human activities on the populations of M. scutellaris, as little genetic structure was detected.

Cobalt chloride induces metaphase when topically applied to larvae and pupae of the stingless bee Melipona scutellaris (Hymenoptera, Apidae, Meliponini)

In order to optimize preparations of bee metaphases, we tested cobalt chloride, which has been used as a metaphase inducer in other organisms, such as hamsters and fish. Four microliters of 65 mM cobalt chloride aqueous solution was topically applied to larval and pupal stages of the stingless bee Melipona scutellaris. The cerebral ganglion was removed after treatment and prepared for cytogenetic analysis. Identically manipulated untreated individuals were used as controls. The number of metaphases was increased 3-fold in treated individuals compared to controls. The micronucleus test showed no mutagenic effects of cobalt chloride on M. scutellaris cells. We concluded that cobalt chloride is a metaphase-inducing agent in M. scutellaris, thus being useful for cytogenetic analyses.

Insights into the Melipona scutellaris (Hymenoptera, Apidae, Meliponini) fat body transcriptome

The insect fat body is a multifunctional organ analogous to the vertebrate liver. The fat body is involved in the metabolism of juvenile hormone, regulation of environmental stress, production of immunity regulator-like proteins in cells and protein storage. However, very little is known about the molecular mechanisms involved in fat body physiology in stingless bees. In this study, we analyzed the transcriptome of the fat body from the stingless bee Melipona scutellaris. In silico analysis of a set of cDNA library sequences yielded 1728 expressed sequence tags (ESTs) and 997 high-quality sequences that were assembled into 29 contigs and 117 singlets. The BLAST X tool showed that 86% of the ESTs shared similarity with Apis mellifera (honeybee) genes. The M. scutellaris fat body ESTs encoded proteins with roles in numerous physiological processes, including anti-oxidation, phosphorylation, metabolism, detoxification, transmembrane transport, intracellular transport, cell proliferation, protein hydrolysis and protein synthesis. This is the first report to describe a transcriptomic analysis of specific organs of M. scutellaris. Our findings provide new insights into the physiological role of the fat body in stingless bees.

Areas of natural occurrence of Melipona scutellaris Latreille, 1811 (Hymenoptera: Apidae) in the state of Bahia, Brazil

The bee Melipona scutellaris is considered the reared meliponine species with the largest distribution in the North and Northeast regions of Brazil, with records from the state of Rio Grande do Norte down to the state of Bahia. Considering the importance of this species in the generation of income for family agriculture and in the preservation of areas with natural vegetation, this study aimed at providing knowledge on the distribution of natural colonies of M. scutellaris in the state of Bahia. Literature information, interviews with stinglessbee beekeepers, and expeditions were conducted to confirm the natural occurrence of the species. A total of 102 municipalities showed records for M. scutellaris, whose occurrence was observed in areas ranging from sea level up to 1,200-meter height. The occurrence of this species in the state of Bahia is considered to be restricted to municipalities on the coastal area and the Chapada Diamantina with its rainforests. Geographic coordinates, elevation, climate and vegetation data were obtained, which allowed a map to be prepared for the area of occurrence in order to support conservation and management policies for the species.

Oral Toxicity of Fipronil Insecticide Against the Stingless Bee Melipona scutellaris (Latreille, 1811)

For a better evaluation of the model using Apis mellifera in toxicology studies with insecticides, the oral acute toxicity of the insecticide fipronil against the stingless bee Melipona scutellaris was determined. The results showed that fipronil was highly toxic to M. scutellaris, with a calculated LC(50) (48 h) value of 0.011 ng a.i./μL of sucrose solution and an estimated oral LD(50) (48 h) of 0.6 ng a.i./bee. Our results showed that M. scutellaris bee is more sensitive to fipronil than the model specie A. mellifera.

Geopropolis from Melipona scutellaris decreases the mechanical inflammatory hypernociception by inhibiting the production of IL-1β and TNF-α

Ethnopharmacological relevanceThe pharmacological activity of geopropolis collected by stingless bees (important and threatened pollinators), a product widely used in folk medicine by several communities in Brazil, especially in the Northeast Region, needs to be studied. ObjectiveThe aim of this study was to evaluate the antinociceptive activity of Melipona scutellaris geopropolis (stingless bee) using different models of nociception. Material and methodsThe antinociceptive activity of the ethanolic extract of geopropolis (EEGP) and fractions was evaluated using writhing induced by acetic acid, formalin test, carrageenan-induced hypernociception, and quantification of IL-1β and TNF-α. The chemical composition was assessed by quantification of total flavonoids and phenolic compounds. ResultsEEGP and its hexane and aqueous fractions showed antinociceptive activity. Both EEGP and its aqueous fraction presented activity in the mechanical inflammatory hypernociception induced by the carrageenan model, an effect mediated by the inhibition of IL-1β and TNF-α. The chemical composition of EEGP and its hexane and aqueous fractions showed a significant presence of phenolic compounds and absence of flavonoids. ConclusionOur data indicate that geopropolis is a natural source of bioactive substances with promising antinociceptive activity.

Pollination services at risk: Bee habitats will decrease owing to climate change in Brazil

Native bees are important providers of pollination services, but there are cumulative evidences of their decline. Global changes such as habitat losses, invasions of exotic species and climate change have been suggested as the main causes of the decline of pollinators. In this study, the influence of climate change on the distribution of 10 species of Brazilian bees was estimated with species distribution modelling. We used Maxent algorithm (maximum entropy) and two different scenarios, an optimistic and a pessimistic, to the years 2050 and 2080. We also evaluated the percentage reduction of species habitat based on the future scenarios of climate change through Geographic Information System (GIS). Results showed that the total area of suitable habitats decreased for all species but one under the different future scenarios. The greatest reductions in habitat area were found for Melipona bicolor bicolor and Melipona scutellaris, which occur predominantly in areas related originally to Atlantic Moist Forest. The species analysed have been reported to be pollinators of some regional crops and the consequence of their decrease for these crops needs further clarification.

Repeated unrewarded scent exposure influences the food choice of stingless bee foragers, Melipona scutellaris

The social organization of foraging processes is a principal key to the ecological success of eusocial insects. Floral odours brought back to the colony by successful foragers are important sources of information underlying an individual’s decision about which resource to collect. Food-source-naive individuals memorize and use this olfactory information when searching for food in the field. Odour familiarization as mechanism underlying the coordination of foraging processes has received little attention so far. Here, we asked whether and to what extent foraging decisions of stingless bees, Melipona scutellaris , are influenced by preceding unrewarded olfactory experiences. In a classical conditioning assay (proboscis extension reflex, PER, assay), foragers were exposed to a scented airflow, during which they either received (experimental group CS+) or did not receive (experimental group CS-) a sugar solution as reward. Subsequently, bees of both experimental groups were introduced into an arena where they could choose between two scented feeders, one of which carried the odour used during the PER assay. Independently of whether foragers had received a sucrose reward during scent exposure, between 70% and 75% of the individuals chose the food source that carried the conditioned odour in the choice arena. Bees from the control groups (harnessed or not; no scent exposure), by contrast, showed no preference for either of the two feeders. These findings point to the importance of preceding olfactory experiences for the food choice of M. scutellaris and suggest that both associative learning during trophallaxis as well as familiarization may influence to a similar extent the foraging decisions of these bees in natural settings.

Por que Melipona scutellaris (Hymenoptera, Apidae) forrageia sob alta umidade relativa do ar?

Há evidências de que a temperatura do ar e a umidade relativa afetam a atividade de voo de espécies de abelhas sociais Meliponini. Em particular, as espécies grandes do gênero Melipona Illiger, 1806 responderiam de maneira mais estreita à variação na umidade relativa. Neste estudo defende-se o argumento de que a umidade relativa seja uma variável de confusão. Nesta linha de argumentação, também foi analisado o papel da coleta de pólen sobre o ritmo diário de forrageio. A robusta Melipona scutellaris (Latreille, 1811) foi usada como modelo e a atividade diária de voo e de forrageio de pólen foi medida em 12 colônias (4 colônias/hábitat), em três tipos de hábitats, que variam principalmente quanto à pluviosidade, na área de distribuição natural desta espécie (Floresta Pluvial, Floresta Sazonal e Transição Floresta Tropical-Cerrados). A maioria da atividade de voo acontece durante a manhã. A atividade de forrageio das colônias foi mais elevada nas primeiras horas do alvorecer, quando a umidade relativa também era alta, frequentemente associada a picos de coleta de pólen. A atividade de voo decresceu abruptamente durante as temperaturas altas ao redor do meio dia. A relação da atividade de voo com a umidade relativa foi altamente significativa e linear, contrastando com a relação significativa e unimodal com a temperatura. Na relação com o forrageio de M. scutellaris, a umidade relativa se configura como uma variável contingente, em hábitats tropicais úmidos, considerando os padrões diários de variação do microclima e de forrageio de pólen. Este último padrão também sustenta a hipótese de partição temporal de fontes florais de pólen.

Five egg-laying queens in a single colony of brazilian stingless bees (Melipona scutellaris Latreille

Polygyny, characterized by the presence of several egg-laying queens, is considered as a temporary colony status. In stingless bees it is rarely observed. This paper reports the first case of natural polygyny in Melipona scutellaris colony, with five egg-laying queens.

Successful maintenance of a stingless bee population despite a severe genetic bottleneck

Stingless bees play an important ecological role as pollinators of many wild plant species in the tropics and have significant potential for the pollination of agricultural crops. Nevertheless, conservation efforts as well as commercial breeding programmes require better guidelines on the amount of genetic variation that is needed to maintain viable populations. In this context, we carried out a long-term genetic study on the stingless bee Melipona scutellaris to evaluate the population viability consequences of prolonged breeding from a small number of founder colonies. In particular, it was artificially imposed a genetic bottleneck by setting up a population starting from only two founder colonies, and continued breeding from it for a period of over 10 years in a location outside its natural area of occurrence. We show that despite a great reduction in the number of alleles present at both neutral microsatellite loci and the sex-determining locus relative to its natural source population, and an increased frequency in the production of sterile diploid males, the genetically impoverished population could be successfully bred and maintained for at least 10 years. This shows that in stingless bees, breeding from a small stock of colonies may have less severe consequences than previously suspected. In addition, we provide a simulation model to determine the number of colonies that are needed to maintain a certain number of sex alleles in a population, thereby providing useful guidelines for stingless bee breeding and conservation efforts.