Abstract 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. study host respectively i (i El Ex cooccurs co occurs co-occurs ii (ii scenario domains territory 1 (BSP time PlioPleistocene Plio period However network test

ABSTRACT Male euglossine bees (Euglossine: Apidae) pollinate flowers of as many as 1,000 Neotropical plant species and there is evidence that blooming in these plants is synchronized with the seasonality of euglossine pollinators. The present study aimed to monitor for two years the phenology of Sarcoglottis acaulis (Orchidaceae - Spiranthinae subtribe) and the seasonality of its pollinators at three Atlantic Forest fragments, two of which surrounded by urban anthropized areas. Phenologies in the three areas were related to abiotic factors, suggesting that precipitation on months prior to the beginning of the flowering period influenced the fructification rates of S. acaulis. Additionally, water shortage during the driest months resulted in vegetative dormancy. Sarcoglottis acaulis sets only a low number of fruits by self-pollination, and the plant’s reproductive success depended on the frequency of its main pollinator, i.e., the male euglossine bees Eulaema atleticana. Lower rates of pollinia removal were observed in areas where this bee is less frequent and, consequently, less fruits were formed, suggesting a high dependency on this pollinator.

Abstract We present the first records of insect visitors and pollinators of Bertholletia excelsa (Lecythidaceae) in a 25 years plantation outside the Amazon biome, flowering and producing Brazil nuts. We installed a platform to observe and photograph the insects. The collected insects were stored, mounted, and identified by specialists. Six species were observed, three of them classified as potential pollinators (Centris lutea, Eulaema nigrita, Eulaema cingulata). The species E. nigrita and E. cingulata were already reported as a pollinators of Brazil nut in Amazon. This is the first record of C. lutea as potential pollinators for B. excelsa.

Resumen Antecedentes y Objetivos: Se ha reportado la visita y recolección de fragancias en frutos del género Vanilla por abejas Euglosinas (Eulaema spp.). Sin embargo, en Vanilla planifolia aun no se ha registrado este comportamiento. Por lo tanto, los objetivos del presente trabajo fueron identificar a los euglosinos que visitaban los frutos maduros de V. planifolia, así como la frecuencia de su visita. Métodos: Se llevaron a cabo 11 muestreos durante un mes (6 de marzo al 6 de abril de 2021) en una plantación experimental de Vanilla planifolia con frutos maduros de vainilla en Veracruz, México. Cada muestreo tuvo una duración de diez horas (08:00 a 18:00 hrs), representando en total 110 horas de esfuerzo de muestreo. Durante los muestreos se colectaron individuos de abejas Euglosinas directamente de los frutos maduros de vainilla para identificarlos a nivel de especie. También se registró la frecuencia de visita por parte de los euglosinos a los frutos maduros de V. planifolia. Resultados clave: Se identificaron cinco especies pertenecientes a tres géneros de Euglossini que visitaban los frutos maduros de Vanilla planifolia: Euglossa hemichlora, E. variabilis, Eulaema cingulata, E. polychroma y Exaerete frontalis. El género Eulaema representó 72% de las visitas a los frutos de V. planifolia. A su vez, la frecuencia de visita estuvo dominada por Eulaema polychroma con 54% del total de las vistas registradas (n=211). Conclusiones: Por primera vez se registran abejas Euglosinas colectando fragancias de los frutos maduros de V. planifolia. Eulaema polychroma es la especie con el mayor porcentaje de visita a los frutos maduros de V. planifolia para recolectar fragancias.

Abstract Background and Aims: Visitation and fragrance collection in fruits of the genus Vanilla by Euglossine bees (Eulaema spp.) have previously been documented. However, in Vanilla planifolia, the most commonly cultivated species, this behavior has not yet been recorded. Thus, the objective of this study was to identify Euglossine visitors of the mature fruits of V. planifolia and to identify the frequency of these visitations. Methods: We held 11 observations set within a month (from March 6 to April 6, 2021) in an experimental Vanilla planifolia plantation with mature fruits of vanilla in Veracruz, Mexico. Each observation lasted for ten hours (from 8:00 to 18:00), representing a total of 110 hours sampling effort. During our observations we collected individuals of Euglossine bees directly from the mature fruits of vanilla to identify them at species level. We also recorded the frequency of Euglossini visits to mature fruits of V. planifolia. Key results: We identified five species belonging to three Euglossini genera visiting mature fruits of V. planifolia: Euglossa hemichlora, E. variabilis, Eulaema cingulata, E. polychroma, and Exaerete frontalis. The genus Eulaema had 72% of visits to V. planifolia fruits. Visitation frequency was dominated by Eulaema polychroma with 54% of total recorded visits (n=211). Conclusions: For the first time, Euglossine bees have been registered collecting scents in mature fruits of V. planifolia. Eulaema polychroma was the species with the highest percentage of visits to mature fruits V. planifolia to collect fragrances.

Abstract 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.

RESUMO O presente estudo avaliou e comparou a fenologia, a biologia da polinização e os sistemas de reprodução de Chamaecrista desvauxii (Collad.) Killip.and Clitoria laurifolia Poir. em uma planície costeira degradada pela mineração de areia em São Paulo, Brasil, entre janeiro de 2006 a maio de 2008. A floração e a frutificação ocorreram na estação quente e chuvosa. Ambas as espécies são autocompativeis, mas apenas C. desvauxii foi dependente do polinizador para produzir frutos. Um pequeno grupo de abelhas, incluindo Eufrisea sp., Eulaema (Apeulaema) cingulata e Bombus morio, tocou as estruturas florais masculinas e femininas e se movimentou entre indivíduos levando a polinizações cruzadas. No entanto, apenas B. morio foi um visitante frequente e um polinizador eficaz. Embora o recrutamento e a sobrevivência da população na área de estudo sejam elevados para ambas as espécies, observou-se reduzida abundância e riqueza de visitantes, indicando uma possível falta de polinizadores e limitação polínica.

ABSTRACT The present study evaluates and compares the phenology, pollination biology and breeding systems of Chamaecrista desvauxii (Collad.) Killip.and Clitoria laurifolia Poir. in a coastal plain degraded by sand mining in São Paulo State, Brazil, from January 2006 to May 2008. Flowering and fruiting events occurred in the warm and rainy season. Both species are self-compatible but only C. desvauxii was pollinator-dependent to set fruits. A small group of bees, comprising Eufrisea sp., Eulaema (Apeulaema) cingulata and Bombus morio, accessed the male and female floral structures and moved among individuals resulting in cross-pollinations. However, only B. morio was a frequent visitor and an effective pollinator. Although recruitment and survival of population in the study area are high for both species, we observed lower abundance and richness of visitors suggesting the possible lack of pollinators and pollen limitation.

Resumo Atualmente, a porção norte da Floresta Atlântica brasileira está drasticamente destruída e os remanescentes florestais raramente excedem 100 hectares. Com uso de iscas odoríferas atrativas aos machos, amostramos a fauna de abelhas-das-orquídeas (Hymenoptera: Apidae: Euglossini) em um fragmento florestal de 118 ha na Reserva Ecológica de Gurjaú, Pernambuco. As abelhas foram ativamente coletadas com redes entomológicas por dois coletores, uma vez por mês, de novembro de 2002 a outubro de 2003. Coletamos 2908 machos de Euglossini pertencentes a 23 espécies, um dos mais altos valores de riqueza registrados para a Floresta Atlântica nordestina. Três quartos das abelhas coletadas pertenceram a apenas duas espécies, Euglossa carolina (50%) and Eulaema nigrita (25%), típicas de áreas abertas e perturbadas e ativas ao longo de todo ano. Remanescentes de floresta como os de Gurjaú, em meio às monoculturas de cana-de-açúcar, podem desempenhar um importante papel na conservação das abelhas-das-orquídeas em ambientes fragmentados como os da Mata Atlântica do nordeste do Brasil.

Abstract 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.

En este trabajo se presenta información sobre la riqueza de especies y abundancia de Euglossini en la zona de transición entre el Cerrado y la selva amazónica, en la cuenca del río Xingu. Las muestras se recogieron en un fragmento de bosque en el municipio de Ribeirão Cascalheira, nordeste de Mato Grosso, Brasil, entre el 1 y 5 de noviembre de 2011. Las sustancias puras de benzoato de bencilo, 1,8 cineol, eugenol y la vainillina fueron utilizadas como cebos para atraer los machos usando red de insectos aunque el salicilato de metilo se utilizó en trampas pasivas. Un total de 168 machos pertenecientes a cuatro géneros fueron registrados, distribuidos en 16 especies. La mayor riqueza de especies se registró en el género Euglossa, aunque Eulaema nigrita fue la especie más abundante en la comunidad. La riqueza de especies varió entre el borde y el primer punto dentro del fragmento. Los machos de abejas de orquídeas eran más activos entre 10:00-11:00 h, y el 1,8 cineol fue la sustancia pura más atractiva. El fragmento estudiado contenía un alto grado de riqueza de especies de abejas de orquídeas en una región de heterogeneidad ambiental extensa, que sigue siendo en gran parte desconocido con relación a su fauna de insectos polinizadores y merece la atención para la elaboración de nuevos inventarios.

This paper presents information about the species richness and abundance of orchid bees in the transitional area between the Cerrado and the Amazon Forest in the Xingu river basin. The males were collected in a forest fragment in the municipality of Ribeirão Cascalheira, northeast Mato Grosso state, Brazil, between 1 and 5 November 2011. Benzyl benzoate, 1.8 cineole, eugenol and vanillin were used as baits, to attract the bees using insect nets and methyl salicylate was used only in the bottle traps. A total of 168 males belonged to four of five Euglossini genera distributed among 16 species were recorded. The greatest species richness was registered in the genus Euglossa, however Eulaema nigrita, was the most abundant Euglossine species in the community. The species richness varied between the edge and the first point within the fragment. The males were more active between 10:00 and 11:00 h, and the 1.8 cineole was the most attractive substance. The fragment studied contained representative species richness of orchid bees in a region of widespread environmental heterogeneity, which is still largely unknown as regards its pollinators and deserves attention for the compilation of new inventories.

O objetivo deste estudo foi avaliar a composição de abelhas Euglossina em três áreas distintas, com monocultura de eucalipto de diferentes idades, utilizando a vegetação nativa como controle, com base nos aspectos de riqueza e abundância. O trabalho foi realizado em três propriedades particulares, localizadas na região Sudoeste de Mato Grosso, em monocultura de eucaliptos de diferentes idades e vegetação nativa (Cerrado). As coletas foram realizadas mensalmente, de dezembro de 2011 a março de 2012, utilizando-se seis essências: eugenol, eucaliptol, vanilina, benzoato de benzila, salicitato de metila e acetato de benzila, das 8 às 16 h. Foram coletados 430 espécimes, de quatro gêneros e 18 espécies. Eulaema nigritaLepeletier, 1841, Euglossa melanotricha Moure, 1967 e Eulaema cingulata Fabricius, 1804 foram as espécies mais abundantes e comuns a todas as áreas estudadas. A área com maior abundância de abelhas foi ApS (166 indivíduos) e com maior riqueza, a Tol (14 espécies). A composição de espécies foi semelhante nas áreas analisadas, e a abundância apresentou dissimilaridade entre a Tol e as áreas SanR e ApS. A área AC (área-controle) apresentou maior abundância (147) e riqueza (n = 15) em relação à monocultura de eucalipto.

The objective of this study was to evaluate the composition of Euglossine bees in three distinct areas, with monoculture of eucalyptus with different ages, using native vegetation as control, based on the aspects of richness and abundance. The work was carried out in three private properties, located in the Southwest region of Mato Grosso in monoculture of eucalyptus with different ages and native vegetation (Cerrado). Samples were collected monthly from December 2011 to March 2012, using six essences: eugenol, eucalyptol, vanillin, benzyl benzoate, methyl salicylate and benzyl acetate, from 8 am to 4 pm. We collected 430 specimens, four genera and 18 species. Eulaema nigrita Lepeletier, 1841, Euglossa melanotricha Moure, 1967 and Eulaema cingulata Fabricius, 1804 were the most abundant species and common to all studied areas. The area with the greatest abundance of bees was ApS (166 individuals) and the one with greater richness, Tol (14 species). The species composition was similar in the analyzed areas, and welth presented dissimilarity between Tol and SanR and ApS. The CA area (control area) showed higher abundance (147) and richness (n = 15) compared to eucalyptus monoculture.

Male bees of the tribe Euglossini collect volatile chemicals secreted by orchids using dense patches of hair on the front tarsi. After collecting chemicals, the bee hovers while transferring these fragrances to invaginations on the hind tibiae. The fragrance collection and hovering behaviours are repeated multiple times. Here I report preliminary field observations on the length of fragrance collection and hovering phases in bees of the Eulaema meriana (Oliver, 1789) mimicry complex visiting the orchid Catasetum discolor in Kavanayén,Venezuela. I observed that in extended visits with many cycles of fragrance collection and hovering, the length of each collection phase gradually increased, while the length of hovering phase was static. This suggests either that chemicals secreted by orchids are in limited supply or that efficiency of fragrance collection drops.

Notes on the systematics of the orchid-bee genus Eulaema (Hymenoptera, Apidae). The classification of the genus Eulaema is modified in order to make it congruent with recent phylogenetic hypotheses based on molecular data. The speciosa group, containing E. peruviana, E. speciosa and related species, is removed from E. (Eulaema) and transferred to E. (Apeulaema). New morphological characters are presented to support the revised scope of the subgenera and their diagnostic features are revised. Six species groups are recognized herein: two in E. (Apeulaema) and four in E. (Eulaema). A list of valid species in each species group and an identification key to males of each of the subgenera and species groups are provided. Finally, an older overlooked designation of a type species for Eulaema is presented in the Appendix.

As faunas de abelhas-das-orquídeas (Hymenoptera: Apidae: Euglossina) dos três maiores remanescentes florestais do Centro de Endemismo Pernambuco, nordeste do Brazil, sendo elas a Estação Ecológica de Murici (ESEC Murici), a RPPN Frei Caneca e um remanescente florestal pertencente à Usina Serra Grande, foram amostradas com o uso de dezessete diferentes iscas aromáticas para atrair machos dessas abelhas. Oito sítios amostrais foram selecionados nas três áreas, onde amostragens foram realizadas sob duas metodologias: coleta ativa com rede entomológica e coleta com armadilhas. Foram coletados 3.479 machos de abelhas euglossinas durante 160 horas no início de outubro de 2012. Sete espécies foram registradas no Centro de Endemismo Pernambuco pela primeira vez. A riqueza da região se mostrou uma das mais altas de toda a Mata Atlântica, e a diversidade em alguns locais, especialmente na ESEC Murici, revelou-se uma das mais altas de toda a região Neotropical. Eulaema felipei Nemésio, 2010, uma espécie que só havia sido registrada na ESEC Murici, não foi encontrada em nenhuma outra área e seu estado de conservação é discutido.

The orchid-bee faunas (Hymenoptera: Apidae: Euglossina) of the three largest forest remnants in the “Centro de Endemismo Pernambuco”, northeastern Brazil, namely Estação Ecológica de Murici (ESEC Murici), RPPN Frei Caneca, and a forest preserve belonging to Usina Serra Grande, in the states of Alagoas and Pernambuco, were surveyed using seventeen different scents as baits to attract orchid-bee males. Eight sites were established in the three preserves, where samplings were carried out using two protocols: insect netting and bait trapping. We collected 3,479 orchid-bee males belonging to 29 species during 160 hours in early October, 2012. Seven species were collected in the “Centro de Endemismo Pernambuco” for the first time. Richness proved to be one of the highest of the entire Atlantic Forest domain, and diversity in some sites, especially at ESEC Murici, revealed to be one of the highest in the Neotropics. Eulaema felipei Nemésio, 2010, a species previously recorded only at ESEC Murici, was found in no other preserve in the region and its conservation status is discussed.

A fauna de abelhas euglossinas da região de Porto Velho, estado de Rondônia, Brasil, próxima ao limite setentrional da Bacia Amazônica, foi amostrada pela primeira vez com o uso de cinco diferentes compostos aromáticos para atrair machos dessas abelhas. Quinhentos e vinte e um machos pertencentes a cinco gêneros e 29 espécies foram coletados em armadilhas durante 26 dias não consecutivos entre novembro de 2011 e janeiro de 2012. Eulaema nigrita Lepeletier, 1841 e Eulaema meriana (Olivier, 1789) foram as espécies mais comuns na região e, juntas, representaram quase 50% do total de abelhas capturadas. Embora a riqueza observada no presente estudo seja semelhante a de outros inventários na Amazônia brasileira, a diversidade encontrada (H′= 2,43) é uma das mais altas já verificadas para a região.

The orchid-bee fauna of the region of Porto Velho, in the state of Rondônia, Brazil, close to the southernmost limits of the Amazon Basin, was surveyed for the first time using five different scents as baits to attract orchid-bee males. Five hundred and twenty-one males belonging to five genera and 29 species were collected with bait traps during 26 non-consecutive days from November, 2011 to January, 2012. Eulaema nigrita Lepeletier, 1841 and Eulaema meriana (Olivier, 1789) were the most common species in the region and, together, represented almost 50% of all collected bees. Although the observed richness conforms to similar inventories in the region, the diversity (H′= 2.43) found in the present study is one of the highest ever recorded for orchid bees in the Amazon Basin.

Abelhas das orquídeas (Hymenoptera, Apidae, Euglossina) em um fragmento florestal do oeste do Paraná. Um inventário de abelhas das orquídeas foi conduzido no Parque Estadual São Camilo, Palotina, Paraná, uma unidade de conservação de cerca de 400 hectares de Floresta Estacional Semidecidual. Três garrafas-armadilha foram instaladas na borda do fragmento, cada uma contendo uma das seguintes essências: 1,8-cineol, eugenol e vanilina. A amostragem foi realizada entre 09 e 15 horas, entre outubro de 2011 e junho de 2012, somando nove dias amostrais. Um total de 186 espécimens distribuídos em sete espécies foram amostrados, Eufriesea violacea com 140 indivíduos foi a mais comum, seguida de Euglossa fimbriata com 31, Euglossa annectans com nove, Eulaema nigrita com quatro, Euglossa cordata, Euglossa pleosticta e Exaerete smaragdina com apenas um indivíduo amostrado cada. De acordo com análise qualitativa e de NMDS a fauna de Euglossina de Parque Estadual São Camilo é representativa de Floresta Estacional Semidecidual, com riqueza comparável a outras áreas no sul da distribuição do grupo. A riqueza de espécie amostrada indica que fragmentos florestais, mesmo que pequenos e isolados, são importantes na conservação destas abelhas.

An orchid bee inventory was carried out in Parque Estadual São Camilo, Palotina, Paraná (Brazil); conservation unit with about 400 hectares of Semidecidual Seasonal forest. Three bait traps were installed at the border of the fragment, each one containing the following fragrances: 1,8-cineole, eugenol, and vanilin. Sampling was carried out from 09am to 03pm, October 2011 to June 2012, summing up nine sampling days. A total of 186 specimens distributed among seven species were sampled. Eufriesea violacea with 140 specimens was the most common species, followed by Euglossa fimbriata (31), Euglossa annectans (9), Eulaema nigrita (4), Euglossa cordata (1), Euglossa pleosticta (1), and Exaerete smaragdina (1). According to qualitative and NMDS analysis, the orchid bee fauna of Parque Estadual São Camilo is representative of Semidecidual Seasonal forest, with richness comparable with other assemblages in the southern distribution of Euglossina. The sampled bee richness indicates that forest fragments, even small and isolated, are important in the conservation of this bees.

A comunidade de abelhas-das-orquídeas (Hymenoptera: Apidae: Euglossina) foi estudada em uma área de transição entre o Cerrado e a Mata Atlântica, de março de 2010 a fevereiro de 2011, na região de Barroso, estado de Minas Gerais, sudeste do Brasil. Foram utilizadas armadilhas aromáticas utilizando-se três tipos de iscas (cineol, eugenol e vanilina) e redes entomológicas para a captura de abelhas em flores. Foram coletados 614 machos de Euglossina nas armadilhas aromáticas, pertencentes a quatro gêneros e quinze espécies, e vinte e cinco espécimes em flores, pertencentes a dois gêneros e três espécies. Eulaema (Apeulaema) nigrita Lepeletier, 1841 foi a espécie mais comum (50% dos espécimes coletados), seguida por Euglossa (Euglossa) truncata Rebêlo & Moure, 1996 (28%). O cineol foi a isca mais atrativa (66,5% dos machos e 13 espécies), seguido pelo eugenol (16% e 9 espécies) e vanilina (13,5% e 4 espécies). Eulaema (Apeulaema) marcii Nemésio, 2009 e Eufriesea auriceps (Friese, 1899) foram atraídas por todas as essências, enquanto as espécies de Euglossa foram coletadas somente em armadilhas contendo cineol ou eugenol.

The community of orchid bees (Hymenoptera: Apidae: Euglossina) was studied at an area in the transition between the Cerrado and Atlantic Forest biomes, from March, 2010 to February, 2011 in the Barroso region, state of Minas Gerais, eastern Brazil. Orchid-bee males were collected with bait traps containing three different scents (cineole, eugenol and vanillin) and with entomological nets for collecting bees on flowers. A total of 614 orchid-bee males were collected using aromatic traps, belonging to four genera and 15 species. Twenty-five female specimens belonging to two genera and at least three species were collected on flowers. Eulaema (Apeulaema) nigrita Lepeletier, 1841 was the most abundant species (50% of collected specimens), followed by Euglossa (Euglossa) truncata Rebêlo & Moure, 1996 (28%). Cineole was the most attractive compound (66.5% of males and 13 species), followed by eugenol (16% and 9 species) and vanillin (13.5% and 4 species). Eulaema (Apeulaema) marcii Nemésio, 2009 and Eufriesea auriceps (Friese, 1899) were attracted to all scents, whereas Euglossa species were collected only in cineole and eugenol.