Eulaema Nigrita Research Articles

Complexity of the Male Perfume of Eulaema nigrita from Forest and Woody Physiognomies of the Brazilian Savanna: Is There a Relationship with Body Size and Wing Wear?

Male orchid bees collect volatile and semi-volatile compounds from the environment for storage and accumulation in specialized hind legs. Later, these compounds form a perfume blend used during courtship to lure conspecific females for mating. Male orchid bees perfume has been suggested to play an important role as a sexual signaling trait involved in pre-mating isolation of species, functioning as an indicator of male genetic quality. Eulaema nigrita Lepeletier (Apidae: Euglossini) is a common species in both forested and woody savanna (Cerrado stricto sensu) physiognomies of the Brazilian savanna biome. By identifying the chemical composition of male E. nigrita perfume, we tested for differences in the bouquet chemical profile in populations from remnants of seasonal semideciduous forest and woody savanna. In addition, we assessed the relation between perfume complexity and morphological traits associated with size and age of males. Our analysis showed a low effect of physiognomies on differences in the perfume chemical profile of sampled males. Nevertheless, we observed significant differences in the chemical profile of individuals from two seasonal semideciduous forest remnants, which suggests an environmental effect in individual bouquet. Wing wear measurements were positively related to perfume complexity, consistent with the premise that perfumes from older individuals are indicators of survival capacity in male orchid bees.

Patterns in Wing Morphology and Fluctuating Asymmetry in Eulaema nigrita along an Altitudinal Gradient in the Brazilian Rupestrian Grassland.

Mountain ecosystems experience abrupt abiotic changes that represent environmental filters for many organisms, shaping their phenotypic expressions. However, little is known about the morphological and symmetric adjustments of native bees along altitudinal gradients. We evaluated the changes on wing morphology, wing size, and vein fluctuating asymmetry (FA) of Eulaema nigrita Lepeletier (Apidae: Euglossini) associated with climatic variables along an altitudinal gradient in the rupestrian grassland (known also as campo rupestre or rupestrian field) of Serra do Cipó, Brazil. Seven sampling points along the altitudinal gradient were selected and distributed among 800 and 1400m.a.s.l., and then, 40 individuals of E. nigrita were collected per each altitudinal point to determine the FA levels and the morphological changes using geometric morphometric techniques. We found that the wing size of E. nigrita decreased with increasing altitude. At the highest altitudes, the levels of FA of the wing veins were greater compared to bees from lower altitudes. We detected significant changes in wing morphology along the altitudinal gradient; bees of lower altitudes showed longer and wider wings than bees of higher altitudes, which had narrower and less elongated wings. Our results show a set of morphological adjustments and phenotypic expressions in E. nigrita associated with the variation in environmental conditions along the altitudinal gradient. We highlight the importance of environmental variables as insect-stressor factors, and that FA and geometric morphometric can be excellent tools for monitoring and evaluating environmental stresses.

Floral visitors of the muricizeiro Byrsonima verbascifolia (L.) rich in the Atlantic forest of northeast Brazil

The muric tree (Byrsonima verbascifolia (L.) Rich) is a native fruit plant used by humans for various purposes, from edible fruits to the medicinal uses of its leaves, bark, and fruits. Bees are the main pollinators of wild and cultivated plants, and without pollination, there is no formation of fruits and seeds, so floral visitors perform ecosystem services in exchange for pollen, nectar, and oil. Muricizeiro offers pollen and oils to its floral visitors, which attracts several species of native bees to its inflorescences, mainly Centris and Epicharis bees, specialists in oil collection. Thus, the presence of muric trees close to the planting area can contribute to the pollination of the cultivated plants. The objective of this study was to survey floral visitors to muricizeiro in São Cristóvão. The work was carried out in the Emília Maria settlement in São Cristóvão, Sergipe, where the floral visiting bees of muricizeiro were captured with an entomological net, for ten days, in the morning and afternoon. Twelve bee species belonging to the Apidae and Halictidae families were collected, with the most abundant species being Euglossa chalybeata (38.41%) and Eulaema nigrita (25.42%). The presence of Eulaema nigrita is related to environmental changes during the implementation of agriculture. The specimens were deposited in the entomological collection of the IFS/Campus São Cristóvão.

Genetic diversity and population structure of two Euglossini bee species in a host-parasite relationship.

In the current study, two euglossine species, Exaerete smaragdina and Eulaema nigrita, a cleptoparasite bee and its host, respectively, were used as models to: (i) access the genetic diversity and population structure of both species, sampled along a wide latitudinal range of Atlantic Forest, where the distribution of El. nigrita and Ex. smaragdina co-occurs; (ii) investigate the evolutionary history of these species through the Atlantic Forest, and in a wider scenario, to examine the evolutionary history of these species across others forest domains. Analyses involved males of El. nigrita and Ex. smaragdina sampled through Brazilian territory, including 19 sites in the Atlantic Forest. Bayesian Skyline Plot (BSP) was used to infer possible climate oscillations on population of both species over time. The BSP revealed stability in effective population size for both species in most of the Plio-Pleistocene period. However, BSP results aligned to the starlike configuration in the haplotype network, neutrality test, and population diversity patterns indicated population expansion of the two species during the late Pleistocene. Our findings suggest areas of potential refugia to the climatic oscillations of the Pleistocene in the Atlantic Forest in the Brazilian states of Espírito Santo for El. nigrita and Pernambuco for Ex. smaragdina.

The key is in variation: Spatial-environmental structuring of the morphological variation of a widespread Neotropical bee (Eulaema nigrita)

Environmental changes alter the selective pressures acting on species, leading to different responses. Morphological variation can increase a species’ ability to occupy different habitats, persist in uncertain environments and stabilize its interactions with other species. We examined the morphological variation (wings, thorax and tibiae) of Eulaema nigrita, a widespread species of euglossine bee (Euglossini, Apidae), from populations at 13 localities in Brazil. We found significant variation in most attributes among all populations, high variation in morphological attributes within populations and seasonality of temperature as the most important factor structuring the morphological variation. Our results provide evidence on how the variation in morphological attributes allows us to more accurately explore the responses of populations to changes in environmental conditions.

Assessment of genetic diversity and population structure of Eulaema nigrita (Hymenoptera: Apidae: Euglossini) as a factor of habitat type in Brazilian Atlantic forest fragments

AbstractIn many organisms, habitat affects ecological and genetic diversity and, for certain species, it is expected that a large population should have higher genetic diversity than a smaller population. We analysed the genetics of males of the orchid bee, Eulaema nigrita (Hymenoptera: Apidae) and examined the links between local abundance and habitat with genetic diversity. We also investigated the impact of landscape features on genetic population structure, through microsatellite and mitochondrial DNA analysis, among populations found across 700 km of Brazilian Atlantic forest fragments. We found that genetic variation was not a function of local abundance, but it correlated significantly with habitat. There was significant but low genetic differentiation among populations. We found a single mitochondrial DNA haplotype in all sequenced specimens, which may be widespread throughout the Atlantic forest. Our results reinforce the idea that orchid bees can fly long distances. High-dispersal capacity, together with insufficient time in eventual isolation, can directly contribute to the high degree of similarity among populations for this species, despite their wide geographical distribution.

Genetic diversity and population structure of orchid bees from the Brazilian savanna

Based on microsatellite markers and non-lethal sampling of orchid bee males, we assessed the genetic diversity and population structure of three species, Euglossa pleosticta, Euglossa imperialis, and Eulaema nigrita, collected from forest remnants in the Brazilian savanna biome. Among these species, El. nigrita has being acknowledged as more tolerant to savanic areas, since it is more frequently found in these habitats than the other two species. Thus, we hypothesized that species more associated with forest areas would show lower levels of genetic diversity and higher levels of population structure, since open areas could represent a barrier to the movement of these species. We observed lower levels of genetic diversity (HE ) in the species highly associated with forest areas (Eg. pleosticta, HE = 0.66; Eg. imperialis, HE = 0.44) compared to El. nigrita (HE = 0.81). Concerning the genetic structure, it was only remarkable among samples of Eg. pleosticta, a species strongly associated with the forest remnants. Despite the documented dispersal capacity of euglossine bees, maintenance of the connections among forest areas in this biome seems to be critical for their conservation in the Brazilian savanna.

Overlap of Ecological Niche Breadth of Euglossa cordata and Eulaema nigrita (Hymenoptera, Apidae, Euglossini) Accessed by Pollen Loads and Species Distribution Modeling

Urban areas can serve as biodiversity refuges for pollinators because of the high diversity of available floral and nesting resources. However, it remains unclear what plant species commonly used for urban landscaping provide floral resources that pollinators actively use. Here, we integrate data from the pollen and species distribution models of two abundant euglossine bees-the large-bodied Eulaema nigrita (Lepeletier, 1841) and the small-bodied Euglossa cordata (Linnaeus, 1758)-in urban areas to investigate their overlap in diet breadth and distribution. We hypothesized that because bees with larger body sizes tend to have larger foraging areas, large-bodied bees would have a wider diet breath than small-bodied bees. Contrary to our hypothesis, we found that Eg. cordata has a wider diet breadth than El. nigrita with the former species showing higher diversity of pollen types collected (per pollen load and on average across pollen loads). Pollen grains from Solanum paniculatum and Tradescantia zebrina represented 63% of the diet of Eg. cordata, whereas pollen from S. paniculatum and Psidium guajava represented 87% of the diet of El. nigrita. After overlaying the distribution of both bee species and the three most important pollen resources, the distribution models revealed that these three plant species can co-occur with both euglossine bees throughout a large portion of eastern Brazil near the coast. Thus, we conclude S. paniculatum, T. zebrina, and P. guajava should be considered key plants for the maintenance of these two urban euglossine bee species. The results of this study provide important information for urban landscaping programs that aim to protect and preserve pollinators.

Range Expansion of the Cleptoparasitic Orchid Bee Aglae caerulea in the Pantanal of Mato Grosso, Brazil

In the present study, a new occurrence of Aglae caerulea Lepeletier & Audinet-Serville is reported within a few km of the seasonal flooded plain limits of the Pantanal in the Paraguay basin, reinforcing the idea that this species coexists with its hostess Eulaema nigrita, one of the most common species catalogued in several habitats surveyed in the biome. After 18 months of sampling and no A. caerulea male attracted to the baits, methyl cinnamate was added to the set of fragrances available in the field. During four weeks in May and one week in June 2018, a total of 11 males of A. caerulea were attracted to the new bait in the gallery forest of São Vicente Range. With this most recent record, we expand the ranges of occurrence to the north-eastern border of the Pantanal of Barão de Melgaço, in Mato Grosso, Brazil. Future expeditions in the Pantanal of Mato Grosso and Mato Grosso do Sul should record this cleptoparasitic species from southern to western Paraguay river basin, to reduce the biogeographical gaps in this peculiar tribe of corbiculate bees. The cleptoparasitic species A. caerulea may be recorded when adequate field studies and collections are made from the seasonal floodplain habitats to karstic habitats (dry forests) along the Pantanal border.

Does a coffee plantation host potential pollinators when it is not flowering? Bee distribution in an agricultural landscape with high biological diversity in the Brazilian Campo Rupestre.

Natural environments within agricultural landscapes have been recognized as reservoirs of biodiversity and, therefore, providers of fundamental ecosystem services to human beings. Bees are the main providers of pollination and thus contribute to the production of food consumed worldwide. In this work, we evaluated the distribution of bees in an agricultural landscape of coffee plantation before and after coffee flowering. We aimed at understanding how richness, abundance and composition of bee communities vary among the different vegetation types within and around the coffee crops. A total of 638 bees were collected - 312 in the dry season and 326 in the rainy season - totaling 85 species. The sampling methods collected different species, which provided complementary sampling. Only Euglossa leucotricha and Eulaema nigrita were recurrent in both seasons and vegetation types. There was no temporal difference in richness or abundance; however, both varied in relation to the vegetation type and were higher in the coffee-native transition area. Diverging from richness or abundance, the composition of the communities differed regarding season and vegetation types. We reinforce the importance of maintaining native vegetation in areas surrounding coffee plantations since the crop poorly hosts pollinators when it is not flowering. Natural and semi-natural areas may act as reservoirs of floral visitors, thus maintaining potential cross-pollination services available to coffee production. © 2020 Society of Chemical Industry.

Species Distribution of Euglossini Bees (Hymenoptera: Apidae) at an Altitudinal Gradient in Northern Santa Catarina

Euglossini bees are found from southern USA to Central Argentina and southern Brazil. Variations in latitude and altitude can influence the distribution of these bees. This study focused in recognizing the Euglossini species in northern Santa Catarina state, evaluating the distribution over the gradient between sea level and 800 meters altitude. The bees were collected in six locations, between Spring and Summer from 2013 to 2015, using cotton balls containing the following odor baits: benzyl benzoate, 1,8 cineole, eugenol, menthol and vanillin. A total of 794 bees were sampled, belonging to 10 different species, including a possible new species. In terms of abundance Eufriesea Cockerell, 1908 (4 species) accounted for 552 individuals, followed by Euglossa Latreille, 1802 (5 species) with 218 and Eulaema Lepeletier, 1841 (2 species) 24 individuals. Five species were not found above altitude of 400 meters. Eufriesea violacea Blanchard, 1840, Euglossa annectans Dressler, 1982, and Eulaema nigrita Lepeletier, 1841 were the only species found in every location along the altitudinal gradient, but their abundance declines toward higher altitudes. The results surpassed the known orchid bee species for Santa Catarina state from 9 to 14 and confirmed the expected tendency of richness and abundance reduction toward the highlands.tendency of richness and abundance reduction toward the highlands.

Unpredicted occurrence of Aglae caerulea in the Pantanal wetland biome and its implications (Apidae: Euglossini)

An unpredicted occurrence of the cleptoparasitic orchid bee Aglae caerulea is announced for the Pantanal wetland biome in midwest Brazil, cataloged in a gallery forest in the Serra das Araras Ecological Station, southwestern Mato Grosso. A single female was cataloged outside the polygons where surveys were recently proposed for new orchid bee inventories in the Neotropical realm. The female found in habitat preoccupied by its hostess Eulaema nigrita is presumed representative to confirm that A. caerulea occurs in sympatry with their host in this wetland. Two recent points of occurrence in the Amazon rainforest of Mato Grosso were included here to update the Aglae distribution map. Following a meticulous literature review, several previous records from tropical moist forests in Panama and spanning from the Caribbean Sea to the Cerrado in central Bolivia and Brazil were used to complete the present record points of A. caerulea in the neotropics. The results demonstrate another distributional gap in euglossines and suggest the need for additional studies to find Aglae in southern Pantanal and farther afield.

Orchid bees (Hymenoptera, Apidae, Euglossini) are seasonal in Seasonal Semideciduous Forest fragments, southern Brazil

Seasonal fluctuations in the abundance of orchid bees have already been reported. The variations in population dynamics may be expected to occur in more predictable and pronounced manners in environments with a clear distinction between rainy and dry seasons, where climatic variables are regarded to be good predictors of populational patterns. The main goal of this paper is to investigate the seasonality of males of orchid bees in fragments of Seasonal Semideciduous Forest in southern Brazil. Data comprise bait samples from five one-year periods on four forest fragments. The seasonality of species abundance was tested with circular statistics. Results suggest two phenological patterns, one for Eufriesea violacea (Blanchard), Eulaema nigrita Lepeletier and Euglossa cordata (Linnaeus), whose abundances are concentrated in late spring and early-middle summer and another for Euglossa fimbriata Moure with a tendency to be collected in middle-late summer and early autumn. These patterns are discussed, as well the possible driven factors, (i) the species life cycle and nesting behavior, (ii) synchrony with resource, and (iii) climate. We can postulate an important impact of climate change in local euglossine assemblage due to the small populations and marked seasonality.

Orchid bees (Apidae: Euglossini) in Cerrado remnants in northeast Brazil

ABSTRACTThere is a general lack of information concerning the diversity of bees belonging to the Euglossini tribe in Cerrado areas closest to the Brazilian Amazon. The state of Maranhão is situated in the northeast Brazilian Cerrado and has become the agricultural frontier of the country due to the advancement of monoculture and cattle farming. These activities have suppressed animal and plant populations in large areas of the Cerrado remnants, for which we have not yet obtained adequate scientific knowledge of local species. The objective of this study was to conduct a survey of Euglossini fauna in the northeast Cerrado. We evaluated the variation in species richness, composition and abundance between two distinct vegetation types: Cerrado sensu stricto (s.s.) and gallery forest. Male bees were captured from 7:00 a.m. to 5:00 p.m. over two consecutive days. Captures were carried out once per month from July 2012 to December 2013, using a combination of passive and active collection techniques, including baited traps, as well as a collector with an entomological net to collect bees near traps. We collected a total of 766 Euglossini males belonging to 24 species and five genera. The most abundant species were Eulaema bombiformis, Eulaema nigrita and Eulaema cingulata for the gallery forest site, whereas Eulaema nigrita, Euglossa melanotricha and Euglossa cordata were more abundant in the Cerrado s.s. The gallery forest yielded a higher number of male Euglossini (n = 503, 21 species) compared with the Cerrado s.s. (n = 263, 16 species). The presence of seven exclusive species in the gallery forest and three in the Cerrado s.s. indicated that both environments are important for the maintenance of Euglossini species in this region and highlight the increasing need for conservation programmes for the protection of Cerrado environments.

New Geographical Records of Two Species ofEufrieseaCockerell, 1908 (Apidae: Euglossini) in Santa Catarina, Brazil, and the Use of a New Fragrance to Attract Orchid Bees

The genus Eufriesea is usually represented by few species, and in most cases, by low number of individuals in samples collected from the Atlantic Forest biome, Brazil. The present study extends the geographic distribution of Eufriesea dentilabris (Mocsary, 1897) and E. mussitans Fabricius, 1787, which are recorded for the first time in the southern state of Santa Catarina, Brazil. Males of E. dentilabris were collected with pollinia of Catasetum flowers (Orchidaceae). We discuss the use of a new aromatic bait with a mint base which is inexpensive and was attractive to four Euglossini species: Eufriesea dentilabris, Eufriesea violacea (Blanchard, 1840), Eulaema cingulata (Fabricius, 1804) and Eulaema nigrita Lepeletier, 1841.

A Quantitative Baseline of Ants and Orchid Bees in Human-Modified Amazonian Landscapes in Paragominas, PA, Brazil.

The lack of effective biodiversity baselines is a major impairment to implement conservation plans. Hence, constructing and updating species lists provides vital information about species distribution records. The Sustainable Amazon Network (in Portuguese Rede Amazônia Sustentável; RAS) is an interdisciplinary research initiative that aims to evaluate land-cover changes effects in eastern Brazilian Amazonia. Within the scope of this project, we sampled ants and orchid bees and herein present a list of species collected in Paragominas, PA, Brazil; the most complete lists of species published to date of these groups for the eastern Amazon. We sampled these insects across several land-cover types, from undisturbed primary forest, through varyingly disturbed primary and secondary forests to production areas (silviculture, pastures and arable fields). In total we recorded 285 species of ants and 36 species of orchid bees. Species richness was higher in primary forests for both groups, followed by production areas. Orchid bees reached their highest richness in secondary forests. For orchid bees, production areas were dominated by a few hyper-dominant species, such as Eulaema nigrita. We acknowledge that the use of different sampling methods would collect additional species, and we recommend this for future assessments if the aim is to make a complete inventory. We expect this study can be used as a baseline for understanding the effectiveness of ongoing changes in forest conservation and land management practices. Finally, this list is of suitable importance in determining conservation status for several taxa described here.

Endocrine cells in the midgut of bees (Hymenoptera: Apoidea) with different levels of sociability

Bees are important models to study the physiological role of endocrine cells. These cells produce hormones and may be open or closed cells depending on whether they have direct or indirect contact with the gut lumen, respectively. Food is digested and absorbed in the insect midgut. The objective of this study was to identify endocrine cells in the midgut of bees of different levels of sociability to understand the function of these cells. The midgut of Centris fuscata, Epicharis flava, Euglossa imperialis, Eulaema nigrita, Frieseomelitta varia, Megachile rava, and Melipona quadrifasciata anthidioides (Hymenoptera: Apoidea) was subjected to immunohistochemistry test for FMRF-amide. The midguts of E. imperialis, E. nigrita, and M. rava showed closed FMRFamide-positive endocrine cells, and those of E. flava, F. varia, and M. quadrifasciata anthidioides showed open cells. The greater number of open FMRFamide-positive cells suggest that this peptide probably regulates the synthesis of digestive enzymes without cell receptor and signal transductors, while closed FMRFamide-positive cells suggest that these peptides may play a role in regulating peristaltic movements of digestive tract. Presence of FMRFamide-positive cells in the bees, regardless of their sociability level, reflects the phylogenetic conservation of the peptide FMRFamide family in these bees.

Diversity and Temporal Variation in the Orchid Bee Community (Hymenoptera: Apidae) of a Remnant of a Neotropical Seasonal Semi-deciduous Forest

Multiple biotic and abiotic variables control the composition, diversity, and temporal fluctuations of insect communities. In particular, the assembly of bee communities is strongly influenced by climatic factors as well as variation in food resource availability, which in turn also fluctuates in response to the same factors. The goal of the present study was to investigate the species composition, the species richness and the abundance of the euglossine bees in a remnant of the seasonal semi-deciduous forest of northeastern Sao Paulo state, and evaluate the temporal variation in those parameters over time. From January to December 1990, males of euglossine bees were sampled using three aromatic baits. We collected 643 males belonging to 12 species and three genera. Euglossa imperialis Cockerell was the most abundant species, followed by Eulaema nigrita Lepeletier and Euglossa melanotricha Moure. The composition and species richness showed temporal variation throughout the year, with the highest values being observed during the rainiest months. Such variations occurred by the presence of males from six species which were sampled only during the rainiest months. Of the five most abundant species, Eg. imperialis and Eg. melanotricha were the only species sampled throughout the year. Only El. nigrita and Eg. melanotricha , had the monthly abundance of males correlated with precipitation. Based on the assumption that male euglossine capture rates reflect actual abundance at the sampled habitats, we believe that Eg. imperialis , usually represented by few male in other studies, has a population very well established in the habitat here studied.

Two common species dominate the species-rich Euglossine bee fauna of an Atlantic Rainforest remnant in Pernambuco, Brazil.

Nowadays, the northern part of the Atlantic Rainforest of Brazil is largely destroyed and forest remnants rarely exceed 100 ha. In a 118 ha forest fragment within a state nature reserve of Pernambuco (Reserva Ecológica Gurjaú), we surveyed the orchid bee fauna (Apidae, Euglossini) using eight different scent baits to attract males. Once a month during one year, the bees were actively collected with entomological nets, from November 2002 to October 2003 by two collectors. We collected 2,908 orchid bee males belonging to 23 species, one of the highest richness values of the Northern Atlantic Rainforest. Bees of only two species, Euglossa carolina (50%) and Eulaema nigrita (25%), which occurred throughout the year, accounted for three quarter of the collected individuals. Both species are typical for open or disturbed areas. Rainforest remnants like those of Gurjaú within the predominant sugar cane monocultures in the coastal plains of the northern Atlantic Rainforest play an important role in orchid bee conservation and maintenance of biodiversity.

Variation in the Abundance of Neotropical Bees in an Unpredictable Seasonal Environment.

This study provides information on the number of orchid bees based on a long-term monitoring study in an antropized savanna region in Southeastern Brazil. Sampling was carried out using chemical lures, and 77 samples were monthly collected to assess the number of individuals as well as the annual and seasonal species fluctuation. The number of species varied significantly among years but not among months, and there was a positive correlation between the number of species and the number of individuals in each sample. Monthly number counts revealed a seasonal pattern for Eulaema nigrita Lepeletier and Exaerete smaragdina Perty, which were more numerous during humid months but peaked in December, January, and February. Different species of Euglossa presented a significant variation in number among years, but not among months, with no pattern along the years. The community and the populations studied were less stable when compared to those of well-preserved habitats of equatorial forests. The El Niño phenomenon of 1997/98 did not result in negative effects in the populations studied; on the contrary, there was a peak in the number of E. nigrita. The amplitude in the yearly variation of the male orchid bee population reflects the evolutionary history of species living in unpredictable seasonal weather that led to the development of particular adaptive traits designed to deal with environmental uncertainties. This study suggests that the plasticity of the life cycle may explain population stability and provide greater resilience to severe climate change events in the future.