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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.

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Habitat loss and fragmentation are drivers of biodiversity loss, such as Euglossini bees in continental regions. Knowledge about these effects on this group of pollinators in coastal regions is still incipient and needs to be further investigated. This study aimed to evaluate the effects of landscape structure on the abundance, richness, diversity and species composition of Euglossini bees on the coast of the Brazilian Amazon. We mapped the surrounding landscape around 48 sampling points in the east of the island of Marajó, Pará, Brazil where we collected bees using chemical baits. We used Generalized Linear Models (GLMs) to evaluate the effects of landscape structure (composition and configuration) on the abundance, richness, diversity and composition of Euglossini bees. We collected a total of 1017 males belonging to four genera and 22 species. Forest cover (%) and landscape heterogeneity were the best predictors of the bee community. Increased forest cover positively affected the abundance, richness and diversity of bees at a local scale. On the other hand, abundance, richness and diversity decreased with increasing landscape heterogeneity, also at a local scale. The hypothesis that the amount of habitat favors Euglossini communities was corroborated by our results. Based on our conclusions, landscapes with greater forest cover can effectively contribute to the conservation of these bees and their pollination services along the Amazon coast.

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Background: The Monteverde region of Costa Rica is a hotspot of endemism and biodiversity. The region is, however, disturbed by human activities such as agriculture and urbanisation. This study provides a list of orchid bees (Hymenoptera: Euglossini) compiled from field surveys conducted during January-October 2019 in the premontane wet forest of San Luis, Monteverde, Costa Rica. We collected 36 species of Euglossine bees across four genera. We provide new geographic distribution and elevation data for eight species in two genera. Due to their critical role in the pollination of orchids and other plants, the distribution and abundance of Euglossine bees has relevance to plant biodiversity and conservation efforts. This is especially important in a region with a high diversity of difficult-to-study epiphytic orchids, such as in the Monteverde region. New information: A total of 2,742 Euglossine male individuals across four genera (Eufriesea, Eulaema, Euglossa and Exaerete) were collected in this study. Updated geographic distributions and elevation ranges were established for eight species of Euglossini in two genera: Eufrieseamussitans (Fabricius, 1787), Eufriesearufocauda (Kimsey, 1977), Euglossadodsoni (Moure, 1965), Euglossadressleri (Moure, 1968), Euglossahansoni (Moure, 1965), Euglossaignita (Smith, 1874), Euglossatridentata (Moure, 1970) and Euglossaturbinifex (Dressler, 1978). These are the first recorded occurrences of these species in the Monteverde region of Costa Rica, according to the Global Biodiversity Information Facility (GBIF) database (https://doi.org/10.15468/9f9kgp). This study also established expanded elevation ranges for Euglossaallosticta, Euglossabursigera, Euglossamixta, Euglossaheterosticta and Euglossamaculabris, though these five species have been previously recorded in the Monteverde region and, thus, are not described in detail here. Additionally, our capture of 123 Eufrieseaconcava individuals is significant, as it indicates its abundance in this region. Prior to this study, there was a single record of E.concava in the Monteverde region, documented in 1993.

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Catasetum is a speciose Neotropical orchid genus of which male and female flowers emit scents acting both as attractant and reward for their exclusive pollinators, male orchid bees (Euglossini: Apidae). In Catasetum, it is well known that flowers display a remarkably morphological sexual dimorphism. However, it remains poorly investigated whether this is also true for floral scents. Here, we investigated the pollination ecology and floral scent traits (chemistry and total emission) of C. maranhense, a species endemic to the Brazilian N/NE region. Males of Euglossa securigera are the only pollinators of C. maranhense. The floral scent of C. maranhense is composed of 29 volatile compounds, with eucalyptol, indole, (E)-Methyl p-methoxycinnamate, and (Z)-Methyl p-methoxycinnamate accounting for more than 80% of the scent bouquet. No sexual dimorphism was detected in any of the traits investigated. We discuss the ecological and evolutionary significance of our findings to Catasetum species and other unisexual perfume plants.

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In this study, through a rapid assessment, we evaluated differences in richness, abundance, species composition and beta diversity of Euglossini bees in preserved areas and areas altered by riverine human populations in the Caxiuanã National Forest (northern Amazon). Our hypotheses were: i) the species richness, diversity, abundance and composition of Euglossini bees differ between the preserved and altered areas because many species are intolerant to small anthropic disturbances; and ii) areas altered by riverine populations have higher values ​​of beta diversity (species dissimilarity between sites) than preserved areas, due to local changes in habitat and increased heterogeneity between sites. We sampled two areas (preserved and altered) and, in each area, four transects were sampled with odorous baits. We used a Student's t test to evaluate differences in richness, abundance, and Shannon-Wiener diversity index. We also evaluated differences in composition and differences in beta diversity between areas. We collected 102 specimens, identified in 18 species and three genera, 63 individuals (61.8% of the total) in preserved areas and 39 individuals (38.2%) in altered areas. Euglossa liopoda (Dressler, 1982) was the most abundant in altered areas and Euglossa imperialis (Cockerell, 1922) the most abundant in preserved areas. Species richness was 2.5 times greater in the transects of preserved areas, and species composition also differed between the sampled areas. In contrast, species abundance did not differ between transects of both areas. Despite our small sample size, this study demonstrated that the richness, composition and beta diversity of Euglossini bees can be potentially affected by local changes in habitat caused by small-scale activities provided by traditional Amazonian groups. Our results indicate the urgency for more comprehensive studies aimed to investigate these relationships.

Neste estudo, por meio de uma avaliação rápida, investigamos diferenças na riqueza, abundância, composição de espécies e diversidade beta de abelhas Euglossini em áreas preservadas e áreas alteradas por populações ribeirinhas na Floresta Nacional de Caxiuanã (norte da Amazônia). Nossas hipóteses foram: i) a riqueza de espécies, diversidade, abundância e composição das abelhas Euglossini diferem entre as áreas preservadas e alteradas, uma vez que muitas espécies são intolerantes a pequenos distúrbios antrópicos; e ii) áreas alteradas por populações ribeirinhas apresentam maiores valores de diversidade beta (dissimilaridade de espécies entre locais) do que áreas preservadas, devido às mudanças locais no habitat e aumento da heterogeneidade entre locais. Amostramos duas áreas (preservadas e alteradas) e, em cada área, foram amostrados quatro transectos com iscas odoríferas. Nós utilizamos testes t de Student, para avaliar diferenças de riqueza, abundância e índice de diversidade de Shannon-Wiener. Também avaliamos as diferenças na composição e as diferenças na diversidade beta entre as áreas. Foram coletados 102 espécimes, em 18 espécies e três gêneros, 63 deles (61,8%) em áreas preservadas e 39 (38,2%) em áreas alteradas. Euglossa liopoda (Dressler, 1982) foi a mais abundante nas áreas alteradas e Euglossa imperialis (Cockerell, 1922) nas áreas preservadas. A riqueza foi 2,5 vezes maior nos transectos de áreas preservadas, e a composição de espécies também diferiu entre as áreas amostradas. Em contraste, a abundância de espécies não foi diferente entre os transectos das duas áreas. Apesar de nosso esforço amostral reduzido, nossos resultados demonstram que a riqueza, composição e diversidade beta das abelhas Euglossini podem potencialmente ser afetadas por mudanças locais no habitat causadas por atividades de pequena escala fornecidas por grupos tradicionais da Amazônia. Esses resultados indicam a urgência por estudos mais extensos no sentido de investigar as relações aqui estudadas.

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Euglossine fauna of a large remnant of Brazilian Atlantic forest in eastern Brazil (Reserva Natural Vale) was assessed along an edge-forest gradient towards the interior of the fragment. To test the hypotheses that the structure of assemblages of orchid bees varies along this gradient, the following predictions were evaluated: (i) species richness is positively related to distance from the forest edge, (ii) species diversity is positively related to distance from the edge, (iii) the relative abundance of species associated with forest edge and/or open areas is inversely related to the distance from edge, and (iv) relative abundance of forest-related species is positively related to distance from the edge. A total of 2264 bees of 25 species was assessed at five distances from the edge: 0 m (the edge itself), 100 m, 500 m, 1000 m and 1500 m. Data suggested the existence of an edge-interior gradient for euglossine bees regarding species diversity and composition (considering the relative abundance of edge and forest-related species as a proxy for species composition) but not species richness.

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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.

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Retention of habitat fragments within the urban matrix can provide critical resources for the maintenance of regional biodiversity while still providing socio-economic value. Euglossini bees are important components in a community as they are important pollinators for economically valuable plants as well as hundreds of orchid species. However, some species are very sensitive to environmental impacts like urbanization. This study presents the role of antique urban fragments in a historical city in Brazil and compares it with a conservation area on the aspects of orchid bee assemblage, such as richness, composition, and abundance. Four fragments inside the city of Ouro Preto and three inside Parque Estadual do Itacolomi (PEIT) were sampled for Euglossini bees. Sorensen similarity index was used to compare community composition. The Mantel test was applied to verify the hypothesis that an urban center is a barrier for the mobility of the individuals. Fourteen Euglossini species from the region were registered. Close to 75% of the sampled bees were collected from the PEIT sampling areas. The fragments presented differences in Euglossini richness and abundance. A majority of the sampled fragments were dominated by the Eulaema cingulata Fabricius, Eulaema nigrita Lepeletier, and Euglossa securigera Dressler species. We found differences on community composition between the fragments localized in PEIT and those located in the urban center. The data suggest that there is a possible flux of individuals between the sampled fragments. The various small forest fragments in Ouro Preto, primarily in backyards, may also serve as stepping stones between sampled fragments.

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This study investigated the orchid-bee community in a conservation gradient of the high-altitude rocky fields in the state of Minas Gerais, Brazil. Sampling was performed at two sites with different anthropic influences: a disturbed area (DA), with exotic plant species, and a preserved area (PA). From September 2009 through February 2011, males of euglossine bees were sampled using aromatic bait-traps. We collected a total of 819 specimens belonging to 11 species and three genera: Euglossa Latreille, Eulaema Lepeletier, and Eufriesea Cockerell. Despite the proximity of DA and PA (about 1.2 km), differences in orchid-bee abundance and richness were observed. Higher abundance was observed in the PA (n = 485) compared with the DA (n = 334). Eight species were common to both sites, and only the DA showed exclusive species. The DA showed higher diversity and higher estimated species richness. Euglossa leucotricha Rebêlo & Moure was the most abundant species at both sites followed by Euglossa melanotricha Moure. Higher abundance and richness were found in the warm rainy season. This study contributes to the knowledge of the orchid-bee fauna in the rocky fields and suggests that the greater resource availability in the DA was responsible for the higher orchid-bee diversity.

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Three new species of orchid bees are described and figured from the Amazon and Atlantic forests of Brazil. Euglossa clausisp. n., Euglossa moratoisp. n., and Euglossa pepeisp. n. are distinguished from their close congeners Euglossa crassipunctata Moure, Euglossa parvula Dressler, and Euglossa sapphirina Moure, previously placed in the subgenus Euglossa (Glossurella) Dressler, 1982, a demonstrably paraphyletic assemblage requiring serious reconsideration. Their affinities with related species are discussed and pertinent characters are figured.

RESUMO

Euglossine bee communities in small forest fragments of the Atlantic Forest, Rio de Janeiro state, southeastern Brazil (Hymenoptera, Apidae). Euglossine bees are important pollinators in forests and agricultural areas. Although the structure of their communities is critically affected by anthropogenic disturbances, little is known about these bees in small forest fragments. The objectives of this study were to analyze the composition, abundance, and diversity of euglossine bee species in nine small fragments of different phytophysiognomies of the Atlantic Forest in southeastern Brazil, and to identify the environmental variables that may be related to the species composition of these communities. Males were sampled quarterly from May 2007 to May 2009 with aromatic traps containing methyl cinnamate, vanillin, eucalyptol, benzyl acetate, and methyl salicylate. A total of 1558 males, belonging to 10 species and three genera of Euglossina were collected. The richness ranged from five to seven species per fragment. Euglossa cordata, E. securigera, Eulaema nigrita e E. cingulata were common to all fragments studied. The diversity differed significantly among areas, ranging from H' = 1.04 to H' = 1.65. The precipitation, phytophysiognomy, and altitude had the highest relative importance over the species composition variation. The results presented in this study demonstrate that small forest fragments are able to support populations of euglossine bee species, most of which are widely distributed and reportedly tolerant to open and/or disturbed areas and suggest that the conservation of such areas is important, particularly in areas that are regenerating and in regions with agricultural matrices where these bees can act as important pollinators.

Comunidade de abelhas Euglossina em pequenos fragmentos de Mata Atlântica no estado do Rio de Janeiro, sudeste do Brasil (Hymenoptera, Apidae). Abelhas Euglossina são importantes polinizadores nas florestas e em áreas agrícolas. Embora a estrutura dessas comunidades seja criticamente afetada por perturbações antrópicas, pouco é conhecido a respeito destas abelhas em pequenos fragmentos florestais. Os objetivos deste estudo foram analisar a composição, abundância e diversidade de espécies em nove pequenos fragmentos florestais de diferentes fitofisionomias no sudeste do Brasil, e identificar as possíveis variáveis ambientais que podem estar relacionadas à composição de espécies de Euglossina. Os machos foram amostrados trimestralmente de maio/07 a maio/09 com o auxílio de armadilhas aromáticas contendo cinamato de metila, vanilina, eucaliptol, acetato de benzila e salicilato de metila. Foram amostrados 1558 machos de três gêneros e 10 espécies. A riqueza variou de cinco a sete espécies por fragmento. Euglossa cordata, E. securigera, Eulaema cingulata e E. nigrita foram comuns a todos os fragmentos estudados. A diversidade diferiu significativamente entre as áreas estudadas, variando de H' = 1.04 até H' = 1.65. A precipitação, o tipo fitofisionômico e a altitude tiveram alta importância relativa sobre a variação da composição de espécies. Os resultados apresentados neste estudo demonstram que pequenos fragmentos podem suportar populações de abelhas Euglossina que, em sua maioria, são amplamente distribuídas e supostamente tolerantes a ambientes abertos e perturbados e sugerem que a conservação dessas áreas pode ser de grande importância, principalmente em regiões em processo de regeneração e com matrizes agrícolas, onde essas abelhas podem atuar como polinizadores.

RESUMO

Diversity of the euglossine bee community (Hymenoptera, Apidae) of an Atlantic Forest remnant in southeastern Brazil. Euglossine bees, attracted to scent baits of cineole, eugenol and vanillin, were collected with entomological nets, from December 1998 to November 1999. Samplings were carried out once a month simultaneously by two collectors positioned in two different sites in an Atlantic Forest remnant in northeastern São Paulo state, Brazil. A total of 859 male euglossine bees, belonging to 13 species and four Euglossini genera were collected. Of the total sample, 506 (12 species) males were captured at site A and 353 (10 species) were collected at site B.In both sites, Euglossa pleosticta Dressler, 1982 was the most abundant species (45.79 percent), followed by Eulaema nigrita Lepeletier, 1841 (20.79 percent). The results of this study supply new information about the diversity of orchid bee fauna in Atlantic Forest remnants as well as show that more than one site is needed to sample these bees in a fragmented landascape.

Diversidade de abelhas Euglossini (Hymenoptera, Apidae) em um remanescente de Floresta Atlântica no sudeste do Brasil. Abelhas Euglossini, atraídas às iscas odoríferas de cineol, eugenol e vanilina foram coletadas com rede entomológica durante os meses de dezembro de 1998 a novembro de 1999, em um remanescente de Floresta Atlântica localizado no nordeste do estado de São Paulo, Brasil. As amostragens foram realizadas, uma vez ao mês, simultaneamente por dois coletores posicionados em dois pontos distintos na área de estudo. No total, 859 machos pertencentes a 13 espécies e quatro gêneros foram coletados em ambos os sítios. Do total de abelhas amostradas, 506 (12 espécies) foram capturadas no sítio A e 353 (10 espécies) no sítio B. Em ambos os sítios, Euglossa pleosticta Dressler, 1982 foi a espécie mais abundante (45,79 por cento), seguida por Eulaema nigrita Lepeletier, 1841 (20,79 por cento). Os resultados deste estudo fornecem informações adicionais sobre a diversidade das abelhas das orquídeas em remanescentes de Floresta Atlântica, bem como mostram que mais de um ponto de amostragem se faz necessário para se obter informações mais precisas sobre as comunidades de Euglossini em paisagens fragmentadas.

RESUMO

A new species of Eufriesea Cockerell (Hymenoptera, Apidae) from northeastern Brazil. Eufriesea pyrrhopyga sp. nov. a short-tongued Eufriesea is described as a new species. It can be easily recognized for its predominantly violet lower frons and thorax, violet tergum 1 contrasting with the strong reddish coloration on the lateral portions of terga 2 to 4 and on entire terga 5 and 6, and head pubescence with contrasting colors, white on the lower two-thirds of the face and black on upper frons and vertex. This new species, collected in Recife (Pernambuco, Brazil), apparently is restricted to the Pernambuco endemic center, and seems to be highly endangered.

Uma nova espécie de Eufriesea Cockerell (Hymenoptera, Apidae, Euglossina) do nordeste brasileiro. Eufriesea pyrrhopyga sp. nov., uma Eufriesea de língua curta, é descrita como espécie nova. Esta espécie pode ser facilmente reconhecida pela cor predominantemente violeta na região inferior da fronte e no tórax; primeiro tergo violeta, contrastando com a coloração avermelhada intensa nas porções laterais dos tergos 2 à 4 e nos tergos 5 e 6; e pela pilosidade da cabeça com cores contrastantes, com pêlos claros nos dois terços inferiores da face e escuros na região superior da fronte e no vértice. Esta nova espécie, coletada em Recife, (Pernambuco, Brasil) está aparentemente restrita ao Centro de Endemismo Pernambuco, e parece correr um sério risco de extinção.

RESUMO

Exaerete kimseyae sp. n., abelha de hábito cleptoparasítico e provavelmente endêmica do Panam , é aqui descrita. Esta nova espécie foi erroneamente identificada como E. trochanterica (Friese, 1910) por Kimsey (1979). Por esse motivo, Anjos-Silva & Rebêlo (2006), desconhecendo a correta identidade de Exaerete trochanterica, descreveram um exemplar desta espécie coletado em Mato Grosso, Brasil como Exaerete guaycuru. Aqui E. guaycuru é colocada como sinônimo júnior de Exaerete trochanterica.

Exaerete kimseyae sp. n., a cleptoparasitic bee apparently endemic to Panama is described. This new species was misidentified by Kimsey (1979) as E. trochanterica (Friese, 1910). For this reason Anjos-Silva & Rebêlo (2006), not knowing the true identity of Exaerete trochanterica, described an individual of this species collected in Mato Grosso, Brazil as a new taxon, Exaerete guaycuru. Here E. guaycuru is placed as junior synonym of Exaerete trochanterica.

RESUMO

Euglossa williamsisp. n. is here described from the lowland Amazonian region in Ecuador and Peru, and as part of a small species assemblage within Euglossa consisting of Euglossa dodsoni Moure and Euglossa obtusa Dressler. An identification key to the males of the group is provided plus detailed figures of the new species and representative illustrations for the others. A brief discussion of the taxonomic and biogeographical implications of the new species is provided. New records in Honduras and Nicaragua are provided for the related Euglossa dodsoni.

RESUMO

Surveys of orchid bees at the Brazilian Atlantic forest have been restricted to a few regions, making difficult to understand latitudinal patterns of distribution and diversity of these bees. For this reason we sampled the euglossine fauna at Atlantic forest areas at the coastal region of São Paulo (Sete Barras, Faz. Morro do Capim: SP3) and state of Paraná (Antonina, Reserva Natural do Rio Cachoeira: PR3), in southern Brazil. In PR3, we also evaluated the efficiency of collecting methods for sampling the fauna, comparing bait traps with direct collecting using entomological nets on fragrance baits. The diversity and abundance of bees was very low: we caught only 39 males of eight species in SP3 (Euglossa iopoecila, Euglossa roderici, Eulaema nigrita, Euglossa annectans, Eulaema cingulata, Euglossa pleosticta, Euglossa viridis and Exaerete smaragdina) and 254 males of six species in PR3 (Euglossa iopoecila, Euglossa annectans, Euglossa stellfeldi, Euglossa roderici, Euglossa pleosticta and Eulaema nigrita). Comparing the sampling methodologies, use of insect nets on fragrance baits (six species; 221 specimens) was more efficient than bait traps (three species; 33 specimens). When comparing the faunas of these two areas with other surveys at the Atlantic forest sites, through a DCA analysis, we found that the two surveys presented in this paper were placed relatively close to each other, but apart from the other sites analyzed, not clustering with the southernmost survey at the subtropical Atlantic forest of Rio Grande do Sul or with the remaining surveys carried out at northern lowland sites of this biome.

Os levantamentos da fauna de abelhas euglossíneas realizados até o momento ao longo da floresta Atlântica são restritos a poucas regiões e não permitem um entendimento mais aprofundado dos padrões latitudinais de distribuição e diversidade dessas abelhas. Por este motivo, duas áreas de floresta Atlântica do sul do Brasil, na planície costeira de São Paulo (Sete Barras, Faz. Morro do Capim: SP3) e do Paraná (Antonina, Reserva Natural do Rio Cachoeira: PR3), tiveram sua fauna de euglossíneos amostrada. Em PR3, foi avaliada também a eficiência de dois métodos alternativos de coleta, fazendo-se a comparação entre armadilhas plásticas, iscadas com fragrâncias, e coleta direta com rede entomológica em iscas odoríferas. A diversidade e abundância das abelhas foram muito baixas: apenas 39 machos de oito espécies foram coletados em SP3 (Euglossa iopoecila, Euglossa roderici, Eulaema nigrita, Euglossa annectans, Eulaema cingulata, Euglossa pleosticta, Euglossa viridis e Exaerete smaragdina) e 254 machos de seis espécies em PR3 (Euglossa iopoecila, Euglossa annectans, Euglossa stellfeldi, Euglossa roderici, Euglossa pleosticta e Eulaema nigrita). A comparação entre os métodos de amostragem mostrou que a coleta direta (seis espécies; 221 espécimes) foi mais eficiente do que o uso de armadilhas (três espécies; 33 espécimes). A análise de correspondência (DCA) mostrou que os dois levantamentos apresentados aqui se posicionaram relativamente próximos entre si, porém afastados dos outros locais comparados, não se agrupando com o levantamento mais meridional nos domínios da floresta Atlântica do Rio Grande do Sul, nem com aqueles conduzidos em áreas de terras baixas mais ao norte nesse bioma.

RESUMO

Surveys of orchid bees at the Brazilian Atlantic forest have been restricted to a few regions, making difficult to understand latitudinal patterns of distribution and diversity of these bees. For this reason we sampled the euglossine fauna at Atlantic forest areas at the coastal region of São Paulo (Sete Barras, Faz. Morro do Capim: SP3) and state of Paraná (Antonina, Reserva Natural do Rio Cachoeira: PR3), in southern Brazil. In PR3, we also evaluated the efficiency of collecting methods for sampling the fauna, comparing bait traps with direct collecting using entomological nets on fragrance baits. The diversity and abundance of bees was very low: we caught only 39 males of eight species in SP3 (Euglossa iopoecila, Euglossa roderici, Eulaema nigrita, Euglossa annectans, Eulaema cingulata, Euglossa pleosticta, Euglossa viridis and Exaerete smaragdina) and 254 males of six species in PR3 (Euglossa iopoecila, Euglossa annectans, Euglossa stellfeldi, Euglossa roderici, Euglossa pleosticta and Eulaema nigrita). Comparing the sampling methodologies, use of insect nets on fragrance baits (six species; 221 specimens) was more efficient than bait traps (three species; 33 specimens). When comparing the faunas of these two areas with other surveys at the Atlantic forest sites, through a DCA analysis, we found that the two surveys presented in this paper were placed relatively close to each other, but apart from the other sites analyzed, not clustering with the southernmost survey at the subtropical Atlantic forest of Rio Grande do Sul or with the remaining surveys carried out at northern lowland sites of this biome.

Os levantamentos da fauna de abelhas euglossíneas realizados até o momento ao longo da floresta Atlântica são restritos a poucas regiões e não permitem um entendimento mais aprofundado dos padrões latitudinais de distribuição e diversidade dessas abelhas. Por este motivo, duas áreas de floresta Atlântica do sul do Brasil, na planície costeira de São Paulo (Sete Barras, Faz. Morro do Capim: SP3) e do Paraná (Antonina, Reserva Natural do Rio Cachoeira: PR3), tiveram sua fauna de euglossíneos amostrada. Em PR3, foi avaliada também a eficiência de dois métodos alternativos de coleta, fazendo-se a comparação entre armadilhas plásticas, iscadas com fragrâncias, e coleta direta com rede entomológica em iscas odoríferas. A diversidade e abundância das abelhas foram muito baixas: apenas 39 machos de oito espécies foram coletados em SP3 (Euglossa iopoecila, Euglossa roderici, Eulaema nigrita, Euglossa annectans, Eulaema cingulata, Euglossa pleosticta, Euglossa viridis e Exaerete smaragdina) e 254 machos de seis espécies em PR3 (Euglossa iopoecila, Euglossa annectans, Euglossa stellfeldi, Euglossa roderici, Euglossa pleosticta e Eulaema nigrita). A comparação entre os métodos de amostragem mostrou que a coleta direta (seis espécies; 221 espécimes) foi mais eficiente do que o uso de armadilhas (três espécies; 33 espécimes). A análise de correspondência (DCA) mostrou que os dois levantamentos apresentados aqui se posicionaram relativamente próximos entre si, porém afastados dos outros locais comparados, não se agrupando com o levantamento mais meridional nos domínios da floresta Atlântica do Rio Grande do Sul, nem com aqueles conduzidos em áreas de terras baixas mais ao norte nesse bioma.

RESUMO

Male Neotropical orchid bees (Euglossini) collect volatile chemicals from floral and non-floral sources and store then in specialized hind tibial structures. The ultimate causes of euglossine fragrance collection remain a mystery. Recent evidence suggests that odoriferous substances play a role in euglossine courtship and serve as indicator of male genetic quality. Males of Eulaema nigrita were observed robbing scents from the detached hind legs of a conspecific male E. nigrita in Belém, Brazil. The hind leg seemed to have been detached during fights between males, since one male was missing a hind leg where the observation was made. This behavior appears to be common among males of E. nigrita since more than one case was observed on the same day. The observation reported here shows that males of E. nigrita with tibiae filled with fragrances are attacked by conspecific males that attempt to steal it.

Machos das abelhas das orquídeas (Euglossini) coletam substâncias voláteis de fontes florais e não florais e armazenam estas em estruturas especializadas nas tíbias posteriores. O motivo pelo qual estas substâncias são coletadas permanece um mistério. Evidências recentes sugerem que estas substâncias são utilizadas durante a corte e são indicadoras da qualidade genética dos machos. Neste estudo, machos de Eulaema nigrita foram registrados roubando substâncias de uma perna posterior arrancada de outro macho de E. nigrita em um parque de Belém (Brasil). A perna posterior parece ter sido arrancada durante lutas entre machos, já que no local de observação havia um macho sem uma perna posterior. Esse comportamento parece ser comum entre machos de E. nigrita, um vez que no mesmo dia de observação foram registrados dois grupos distintos de machos voando e lutando ao redor de uma perna posterior arrancada. A observação registrada neste estudo mostra que machos de E. nigrita, que apresentam pernas cheias de essências, são atacados por machos da mesma espécie que procuram roubar as fragrâncias armazenadas.

RESUMO

Spatial distribution patterns of Euglossina bees (Hymenoptera, Apidae) in the Neotropical region. Orchid bees (Apini, Euglossina) have a mainly Neotropical distribution, comprising, approximately, 200 species and five genera. Several local fauna surveys are available in the literature, but comparative studies on the Euglossina composition and distribution patterns are still scarce. The aim of this study is to analyze published data from 29 assemblages in order to understand the spatial distribution patterns of the sampled areas along the Neotropics. Ordination procedures (DCA and NMDS) were employed in order to describe the groupings of assemblages according to orchid bees occurrences. The Central America and Amazonian forests localities formed cohesive groups in both analyses, while Atlantic Forest localities were more dispersed. Areas on the eastern border of the Amazon shared characteristic of transitional areas between this sub-region and the Atlantic Forest. Moreover, analysis of variance among the first DCA axis and variables showed significant influence of latitudinal, longitudinal and rainfall gradients, as biogeographical sub-regions on Euglossina's assemblages groupings. The general pattern is congruent with previously proposed biogeographical scenarios for the Neotropical region. The DCA results also help to identify, independently, the faunal elements inherent to the different studied forested formations.

Abelhas das orquídeas (Apini, Euglossina) apresentam distribuição principalmente Neotropical, com cerca de 200 espécies e cinco gêneros descritos. Muitos levantamentos locais de fauna estão disponíveis na literatura, mas estudos comparativos sobre a composição e distribuição dos Euglossina são ainda escassos. O objetivo deste estudo é analisar os dados disponíveis de 29 assembleias a fim de entender os padrões gerais de distribuição espacial nas áreas amostradas ao longo do Neotrópico. Métodos de ordenação (DCA e NMDS) foram utilizados para descrever os agrupamentos de assembleias de acordo com as ocorrências de abelhas das orquídeas. As localidades de florestas da América Central e da Amazônia formaram grupos coesos em ambas as análises, enquanto as localidades de Mata Atlântica ficaram mais dispersas nos gráficos. Localidades na margem leste da Amazônia aparecem como áreas de transição características entre esta sub-região e a Mata Atlântica. As análises de variância entre o primeiro eixo da DCA e variáveis selecionadas apresentaram valores significantes quanto à influência dos gradientes de latitude, longitude e precipitação, bem como das sub-regiões biogeográficas nos agrupamentos das assembleias. O padrão geral encontrado é congruente com os padrões biogeográficos previamente propostos para a região Neotropical. Os resultados do DCA auxiliam ainda a identificar, de forma independente, os elementos das faunas de cada uma das formações vegetais estudadas.

RESUMO

Spatial distribution patterns of Euglossina bees (Hymenoptera, Apidae) in the Neotropical region. Orchid bees (Apini, Euglossina) have a mainly Neotropical distribution, comprising, approximately, 200 species and five genera. Several local fauna surveys are available in the literature, but comparative studies on the Euglossina composition and distribution patterns are still scarce. The aim of this study is to analyze published data from 29 assemblages in order to understand the spatial distribution patterns of the sampled areas along the Neotropics. Ordination procedures (DCA and NMDS) were employed in order to describe the groupings of assemblages according to orchid bees occurrences. The Central America and Amazonian forests localities formed cohesive groups in both analyses, while Atlantic Forest localities were more dispersed. Areas on the eastern border of the Amazon shared characteristic of transitional areas between this sub-region and the Atlantic Forest. Moreover, analysis of variance among the first DCA axis and variables showed significant influence of latitudinal, longitudinal and rainfall gradients, as biogeographical sub-regions on Euglossina's assemblages groupings. The general pattern is congruent with previously proposed biogeographical scenarios for the Neotropical region. The DCA results also help to identify, independently, the faunal elements inherent to the different studied forested formations.

Abelhas das orquídeas (Apini, Euglossina) apresentam distribuição principalmente Neotropical, com cerca de 200 espécies e cinco gêneros descritos. Muitos levantamentos locais de fauna estão disponíveis na literatura, mas estudos comparativos sobre a composição e distribuição dos Euglossina são ainda escassos. O objetivo deste estudo é analisar os dados disponíveis de 29 assembleias a fim de entender os padrões gerais de distribuição espacial nas áreas amostradas ao longo do Neotrópico. Métodos de ordenação (DCA e NMDS) foram utilizados para descrever os agrupamentos de assembleias de acordo com as ocorrências de abelhas das orquídeas. As localidades de florestas da América Central e da Amazônia formaram grupos coesos em ambas as análises, enquanto as localidades de Mata Atlântica ficaram mais dispersas nos gráficos. Localidades na margem leste da Amazônia aparecem como áreas de transição características entre esta sub-região e a Mata Atlântica. As análises de variância entre o primeiro eixo da DCA e variáveis selecionadas apresentaram valores significantes quanto à influência dos gradientes de latitude, longitude e precipitação, bem como das sub-regiões biogeográficas nos agrupamentos das assembleias. O padrão geral encontrado é congruente com os padrões biogeográficos previamente propostos para a região Neotropical. Os resultados do DCA auxiliam ainda a identificar, de forma independente, os elementos das faunas de cada uma das formações vegetais estudadas.