Abstract Surveys of local Euglossini faunas have largely focused on forests, considering the relationship that orchid bees have with such environments. So, large areas of Caatinga and even Cerrado are yet to be inventoried. Besides the relevance of knowing those faunas themselves, understanding the distribution of species in the dry diagonal of South America is central also to understanding the patterns of richness and endemism of orchid bees in the Amazon and Atlantic Forest. Orchid bees were collected in an area of shrubby Caatinga at the locality of Três Irmãos, municipality of São José do Piauí, Piauí State, northeastern Brazil, using traps baited with aromatic compounds, from October, 2022 to November, 2023. Fifty-nine individuals of five species were sampled, and Euglossa cordata (Linnaeus, 1758) was the most common species, followed by Eulaema nigrita Lepeletier, 1841. Data collected in the region reinforce what is already known regarding the general patterns of orchid bees in the Caatinga biome: assemblages with a reduced number of species, mostly composed of widely distributed species, low abundance of individuals and marked seasonality.

Resumo Amostragens das faunas locais de Euglossini vem focando principalmente em florestas, considerando a relação entre essas abelhas e ambientes florestais. Assim, áreas extensas da Caatinga e mesmo do Cerrado permanecem sem inventariamentos sistematizados. Além da relevância de conhecer tais faunas, entender a distribuição das espécies na diagonal seca da América do Sul é também central para entendermos os padrões de riqueza e endemismo das abelhas Euglossini na Amazônia e Floresta Atlântica. Abelhas-das-orquídeas foram coletadas em uma área de Caatinga arbustiva na localidade de Três Irmãos, município de São José do Piauí, Piauí, Brasil, usando armadilhas com iscas-odores, entre outubro de 2022 e novembro de 2023. Cinquenta e nove indivíduos de cinco espécies foram amostrados, sendo Euglossa cordata (Linnaeus, 1758) a espécie mais abundante, seguido por Eulaema nigrita Lepeletier, 1841. Os dados coletados na região reforçam o que já se conhece em termos dos padrões gerais das faunas destas abelhas na Caatinga: assembleias com riqueza reduzida de espécies, majoritariamente compostas por espécies de ampla distribuição, abundância reduzida e sazonalidade bastante marcada.

Abstract Orchid bees are a conspicuous and ecologically important group of insects, commonly distributed at medium and low altitudes in tropical ecosystems. Therefore, new recordings of orchid bees at higher altitudes are interesting. Here we report the presence of two species of orchid bees in urban and peri-urban environments within the inter-Andean valleys in the province of Azuay in southern Ecuador at more than 2,200 m. One male of Eulaema (Apeulaema) polychroma (Mocsáry, 1899) and a female of Euglossa (Euglossa) cf. charapensis Cockerell, 1917, were recorded in the city of Cuenca at 2,550 m, and several females of Eg. (Eg.) cf. charapensis in the surroundings of the city of Gualaceo at 2,264 m. These new altitude distribution records represent the highest for the genus Euglossa in Ecuador. Also, they show the great altitude dispersal capacity, and high adaptability of these insects to urban and peri-urban environments. Finally, we proposed the Jubones river basin as a potential migration route of these bees from lowland areas in the western foothills of the Andes to the inter Anden valleys of Cuenca and Gualaceo.

Resumen Las abejas de las orquídeas son un grupo de insectos conspicuos y ecológicamente importantes, comúnmente distribuidos a altitudes medias y bajas en ecosistemas tropicales. Por ello, son interesantes los nuevos reportes de abejas de las orquídeas en elevaciones más altas. Aquí se reporta la presencia de dos especies de abejas de las orquídeas en ambientes urbanos y periurbanos dentro de los valles interandinos en la provincia de Azuay en el sur de Ecuador a más de 2.200 m. Un macho de Eulaema (Apeulaema) polychroma (Mocsáry, 1899) y una hembra de Euglossa (Euglossa) cf. charapensis Cockerell, 1917, fueron registrados en la ciudad de Cuenca a 2.550 m, y varias hembras de Eg. (Eg.) cf. charapensis en los alrededores de la ciudad de Gualaceo a 2.264 m. Estos nuevos registros de distribución altitudinal representan los más altos para el género Euglossa en Ecuador. Además, muestran la gran capacidad de dispersión altitudinal, y alta adaptabilidad de estos insectos a ambientes urbanos y periurbanos. Finalmente, proponemos la cuenca del río Jubones como una ruta potencial de migración de estas abejas desde zonas bajas en las estribaciones occidentales de los Andes hasta los valles interandinos de Cuenca y Gualaceo.

Abstract The first natural hybrid of the genus Gongora is described for the department of Copán, Honduras, between Gongora truncata and Gongora batemanii (=Gongora cassidea). The nothospecies described here presents intermediate characteristics between both species, such as setaceous projections on the lip, a large callus, spatulate epichile, and a cucullate hard dorsal sepal. The identity of a specimen from the Herbarium Jany Renz Botanical Institute, University of Basel, Switzerland, corresponds to the same hybrid described here. It was erroneously determined as Gongora saccata (=Gongora seideliana). The clarification of the synonymy of Gongora saccata and relevant aspects regarding the pollination mechanisms and reproductive barriers of both parent species are also discussed.

Resumen Se describe el primer híbrido natural del género Gongora, entre Gongora truncata y Gongora batemanii (=Gongora cassidea). La notoespecie que aquí se describe presenta caracteres intermedios entre ambas especies, como las proyecciones setáceas en el labio, un callo grande, el epiquilo espatulado y el sépalo dorsal fuertemente cuculado. También se discute la identidad de un ejemplar del Herbarium Jany Renz Botanical Institute, University of Basel, Suiza, el cual corresponde al mismo híbrido aquí descrito. Fue erróneamente determinado como Gongora saccata, (=Gongora seideliana). Se discute también la sinonimia de Gongora saccata, y aspectos relevantes en cuanto a los mecanismos de polinización y barreras reproductivas de ambas especies parentales.

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.

RESUMEN Los bioindicadores son organismos que determinan el impacto ambiental de un ecosistema y se utilizan a los euglossinos por responder a cambio ambientales, son de fácil observación, y su taxonomía es bien conocida. El objetivo del estudio fue evaluar calidad ambiental de un bosque a través de las abejas de las orquídeas como bioindicadores. En esta investigación, se realizaron colectas a nivel de sotobosque, por medio de “Bottle Traps”, y colectas manuales por método de zigzag, en el cual se emplearon redes entomológicas, las abejas serán atraídas con atrayentes químicos como: aceite de eucalipto, esencia de eugenol y esencia de vainilla. Lo cual obtuvimos una abundancia bastante al alta con una captura de 1024 individuos y una riqueza de 38 especies, el género que domino el estudio fue ele genero Euglossa con 89,5%, seguido por el género Eulaema con 9,6% y género Eufriesea con apenas un 0,8%, para el género Exaerete que no se logra capturar individuos, La curva de completitud para el muestreo general realizado permite observar una representatividad del 99%. En conclusión, consideramos que la calidad ambiental en Cerro Llorón, a pesar de las acciones antrópicas se encuentra bastante estable, porque encontramos un abundancia y riqueza de especie bien elevada.

ABSTRACT Bioindicators are organisms that determine the environmental impact of an ecosystem and euglossine are used for responding to environmental changes, they are easy to observe, and their taxonomy is well known. The study's objective was to evaluate a forest's environmental quality through orchid bees as bioindicators. In this investigation, collections were made at the undergrowth level by means of "Bottle Traps" and manual pools by zigzag method, in which entomological networks were used; the bees will be attracted by chemical attractants such as eucalyptus oil, the essence of eugenol and vanilla essence. We obtained a relatively high abundance with capture of 1024 individuals, and a richness of 38 species, the genus that dominated the study was the genus Euglossa with 89.5%, followed by the genus Eulaema with 9.6% and the genus Eufriesea with just 0.8 %, for the genus Exaerete that it is not possible to capture individuals, The completeness curve for the general sampling carried out allows us to observe representativeness of 99%. In conclusion, despite anthropic actions, the environmental quality in Cerro Llorón is quite stable because we found a very high abundance and species richness.

Resumen Las abejas euglosinas son importantes polinizadores de múltiples especies de plantas neotropicales, pero en muchas localidades de Colombia existe poca información sobre su presencia. El objetivo de este estudio fue documentar el cambio en la riqueza y abundancia de especies de las abejas de las orquídeas (Apinae: Euglossini) durante las temporadas seca y lluviosa en tres ambientes (bosque de galería, sabana inundable, y un sendero con vegetación secundaria) del departamento de Arauca, Colombia. Los especímenes se recolectaron por captura directa usando cebos libres y la instalación de 32 trampas de botella y cuatro tipos de cebo. La intensidad diaria del muestreo fue de siete horas (7:00-14:00) durante 10 días consecutivos en cada temporada climática. Se recolectaron 367 especímenes pertenecientes a tres géneros y 17 especies que representaron entre el 81,1 y el 91,9 % de las especies esperadas en la zona de estudio. La sabana inundable y el sendero ecológico fueron los ambientes con mayor riqueza de especies y abundancia, comparados con el bosque de galería. Durante la temporada lluviosa se registraron 16 especies (ocho exclusivas) y en la seca, nueve especies (una exclusiva). Se registró una mayor riqueza y abundancia de especies durante la época lluviosa. Este es el primer estudio de abejas euglosinas en las sabanas del departamento de Arauca; se reporta una diversidad comparable a otras localidades de Colombia y otros países neotropicales.

Abstract Euglossine bees are important pollinators of multiple neotropical plant species; however, in many Colombian locations, there is little information about their occurrence. Our objective was to document the change in the richness and abundance of orchid bee species (Apinae: Euglossini) during the dry and rainy seasons in three environments (gallery forest, floodplain, and a path with secondary vegetation) in the department of Arauca, Colombia. Specimens were collected by direct captures using free baits, 32 bottle traps, and four types of bait. The daily intensity of sampling was seven hours (7:00-14:00) for 10 consecutive days in each climatic season. We collected 367 specimens belonging to three genera and 17 species, which represent between 81,1% and 91,9% of the expected species in the study area. The flooded savannah and the path with secondary vegetation were the environments with the highest species richness and abundance compared to the gallery forest. During the rainy season, 16 species were recorded (8 of them exclusive) and nine species (one of them exclusive) in the dry season. There were higher richness and abundance of species during the rainy season. This is the first study of Euglossini bees in savannas of the department of Arauca where our results indicate a diversity comparable to other locations in Colombia and other Neotropical countries.

Abstract The predatory activities of Apiomerus duckei Costa Lima, Seabra & Hathaway, 1951, Apiomerus pilipes (Fabricius, 1787) and Apiomerus luctuosus Costa Lima, Seabra & Hathaway, 1951 (Hemiptera: Reduviidae: Harpactorinae: Apiomerini) on orchid bees (Hymenoptera: Apidae: Apinae: Euglossini) in odoriferous traps in the influence area of Santo Antonio Hydroelectric Power Plant, Rondonia State, Brazil, and of Cosmoclopius annulosus Stal, 1872 (Hemiptera: Reduviidae: Harpactorinae: Harpactorini) on the bee Ceratina rupestris Holmberg, 1884 (Hymenoptera: Apidae: Apinae: Xylocopini: Ceratinina), in an experimental area cultivated with canola in Passo Fundo, Rio Grande do Sul State, Brazil, are recorded by the first time.

Resumen Se registran por primera vez las actividades depredadoras de Apiomerus duckei Costa Lima, Seabra y Hathaway, 1951, Apiomerus pilipes (Fabricius, 1787) y Apiomerus luctuosus Costa Lima, Seabra y Hathaway, 1951 (Hemiptera: Reduviidae: Harpactorinae: Apiomerini) sobre abejas orquídeas (Hymenoptera: Apidae: Apinae: Euglossini) en trampas odoríferas ubicadas en el área de influencia de la Central Hidroeléctrica Santo Antonio (HEP), Estado de Rondonia, Brasil, y de Cosmoclopius annulosus Stal, 1872 (Hemiptera: Reduviidae: Harpactorinae: Harpactorini) sobre la abeja Ceratina rupestris Holmberg, 1884 (Hymenoptera: Apidae: Apinae: Xylocopini: Ceratinina), en un área experimental cultivada con canola en Passo Fundo, Rio Grande do Sul State, Brasil.

RESUMO 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.

ABSTRACT 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.

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.

RESUMO As florestas ripárias no Brasil são importantes ecossistemas que sustentam uma enorme biodiversidade. Apesar de protegidas pela legislação brasileira, elas têm sofrido grandes impactos decorrentes da fragmentação florestal. As abelhas das orquídeas constituem um grupo chave de polinizadores na região Neotropical, porém, pouco se sabe sobre suas assembleias em florestas ripárias. Nós avaliamos o papel de fragmentos de floresta ripária e de terra-firme na conservação e manutenção da fauna de abelhas das orquídeas em uma paisagem urbana no sudoeste da Amazônia. Especificamente, avaliamos se assembleias de abelhas de fragmentos ripários e de terra-firme diferem significativamente em abundância, riqueza e composição de espécies. Também avaliamos se a abundância e a riqueza de espécies variam em função do tamanho do fragmento. Machos de abelhas foram atraídos por iscas odoríferas e coletados com redes entomológicas em 10 fragmentos florestais. Não houve diferença significativa entre fragmentos ripários e de terra-firme quanto à abundância, riqueza e composição de espécies, mas houve uma correlação positiva entre o tamanho do fragmento e a riqueza e abundância de espécies. Nossos resultados sugerem que, em uma paisagem urbana, os fragmentos de floresta ripária e de terra firme ainda podem manter 62,7% do número de espécies de abelhas das orquídeas conhecido para a região, reforçando o valor da conservação desses remanescentes florestais. Nossos dados indicam que esses fragmentos fornecem um habitat potencialmente importante para a manutenção das populações locais de abelhas na paisagem.

ABSTRACT Riparian forests are important ecosystems that support an enormous biodiversity in Brazil. Despite being protected under Brazilian legislation, these forests suffer great impact from the fragmentation of habitats. Orchid bees are a key group of pollinators in the Neotropical region, yet few data are available on the assamblage structure of these bees in riparian forests. We evaluated the role of fragments of riparian and terra-firme forest on the conservation and maintenance of orchid bees in an urban landscape in the southwestern Amazon basin. Specifically, we evaluated whether bee assemblages in riparian and terra-firme forests differed significantly in abundance, species richness and composition. We also evaluated whether species richness and abundance of bees vary with the size of the forest fragment. Male bees were attracted using odoriferous baits and collected with entomological nets in 10 forest fragments. There was no significant difference between riparian and terra-firme fragments in species abundance, richness and composition, but there was a positive correlation between fragment size and species richness and abundance. Our results suggest that, in an urban landscape, the remaining riparian and terra-firme forest fragments still could maintain 62.7% of the orchid bee species known to occur in the region, reinforcing the conservation value of these forest remnants. Our findings indicate that these fragments provide a potentially important habitat for the maintenance of local bee populations in the landscape.

Resumen En este documento presentamos una actualización de la información concerniente al género Eufriesea para Colombia. Se describe la hembra de Eufriesea dressleri (Kimsey, 1977), que era la única hembra del grupo elegans aún no descrita. Se propone una clave taxonómica para su identificación y se extiende el rango de distribución de Eufriesea dressleri, Eufriesea concava, Eufriesea magretti y Eufriesea pulchra para Colombia, incluidos nuevos registros altitudinales.

Abstract In this paper, we present an update of the information concerning the genus Eufriesea for Colombia. We describe the female Eufriesea dressleri (Kimsey, 1977), the only female of the elegans group not yet described. A taxonomic key is proposed for its identification and the range of distribution of Ef. dressleri, Eufriesea concava, Eufriesea magretti, and Eufriesea pulchra is extended for Colombia including new altitudinal records.

Resumo Foram realizadas observações a respeito da biologia reprodutiva de uma espécie de Rapateaceae recentemente descrita (Saxofridericia brasiliensis) em uma área de Campina Fechada periodicamente alagada. Durante o período de floração, as inflorescências foram ensacadas com o intuito de identificar se a espécie forma frutos por meio de autopolinização espontânea. A espécie apresenta tricomas na base das pétalas que se coraram com o uso de Vermelho Neutro e possui como principais agentes polinizadores fêmeas de nove espécies de Euglossa, que realizam a coleta de pólen por meio da vibração das anteras. Contudo novos estudos são necessários para entender por completo as estratégias reprodutivas para a família, em virtude de relatos da existência de polinização por beija-flores na tribo Schoenocephalieae dada a presença de nectários.

Abstract The reproductive biology of Saxofridericia brasiliensis species a recently described species, was observed in an area of periodically flooded (“Campina”) in the Amazon region. During the flowering period, inflorescences were bagged to identify if the species could form fruits through spontaneous self-pollination. The flowers presents trichomes at the base of the petals that stained by neutral red. The main pollinators were females of nine species of Euglossa, which collect pollen by vibrating the anthers. However, new studies are needed to fully understand the reproductive strategies in the family, as the pollination by hummingbirds was reported in the tribe Schoenocephalieae, due to the presence of nectaries.

ABSTRACT Bait traps are effective and commonly used method in the studies of orchid bees. Important questions in the context of this method, including those related to bait dispersion, how long baits remain attractive, the distance from which males are supposed to be attracted to lures and so on, are still open subjects. Data on the attractiveness of bait traps that have remained in the field during two weeks in a large Atlantic forest preserve are presented. Four main results emerge from the data: (i) the abundance of specimens collected per day decreased in all the attractants as the traps were left on the field; (ii) despite this decrease, the absolute number of individuals collected after eight and fifteen days is remarkably, mostly in eugenol and vanillin baits; (iii) the vast majority of species, 22 of 25, was already collected on the first sample day; (iv) a consistent variation in the relative abundance of individuals collected in each scent as collections were made. We urge that bait traps should not be left in the field beyond what is strictly necessary since there is a real possibility of collecting a significant number of individuals as these traps remain available.

Temnadenia odorifera is an endemic species from the Brazilian Atlantic Forest. This study was developed in order to identify the volatile compounds emitted by the living flowers and nectar, to evaluate the temporal pattern of scent emission, and the sugars composition of its nectar. Analyses of the flower scent by dynamic headspace in vivo, of nectar sugar composition and studies on floral biology were performed. Twenty-three volatile compounds were identified in the flowers scent. The total amount of odor emitted by flowers varied significantly throughout anthesis, ranging from 10232.7 ng g-1 (9 to 12 h) to 620.2 ng g-1 (15 to 18 h). 2-Phenylethanol and (E)-cinnamyl alcohol were the major compounds. Concentration ratio between disaccharides and the sum of hexoses ranged from 2.3 to 3.04, which can be correlated to the physiological needs inherent to big bees, the most frequent insects in T. odorifera. Analysis of the chemical composition of T. odorifera flowers provided a broader understanding of the mechanisms responsible for plant-insect interactions.