VARIABILIDADE MORFOMÉTRICA E ASSIMETRIA DAS ASAS DA ABELHA EUGLOSSA CORDATA (LINNEAUS) (HYMENOPTERA: APIDAE: EUGLOSSINI)

As abelhas Euglossini são fundamentais para a polinização em ambientesflorestais (Roubik & Hanson, 2004). Além disso, algumas espécies desses insetosfornecem esse serviço ecológico em paisagens urbanas, como Euglossa cordata(Linneaus, 1758), espécie tolerante a perturbações antrópicas e registrada em altaabundância em ambientes urbanos (López-Uribe et al., 2008).

Morphometric Variability among Populations of Euglossa cordata (Hymenoptera: Apidae: Euglossini) from Different Phytophysiognomies

Geometric morphometrics is a tool capable of measuring the response of organisms to different environmental pressures. We tested the hypothesis that E. cordata wing morphometry, as an indicator of response to environmental pressure, it would vary depending on habitat changes, in the Atlantic Forest, Savanna and dry forest (Caatinga). For analysis of wing shape and size, 18 landmarks were digitized at the intersections of the wing veins 348 individuals. Except for the two populations sampled in Chapada Diamantina, the wing shape had significant statistical variations among the populations (p < 0.05). The wing size variation was also statistically significant among populations (p < 0.05). Although E. cordata is a species tolerant to different environments, the observed morphometric variability may be related to population adaptations to the conditions of each phytophysiognomy.

Pollen Analysis of the Post-Emergence Residue of Euglossa Bees (Apidae: Euglossini) Nesting in an Urban Fragment

Euglossini bees are considered pollinators of a wide variety of plants in the Neotropical region, but little is known about their floral preferences. In this study, we identified the botanical species used as pollen and nectar sources by three Euglossa species (Euglossa cordata, Euglossa townsendi, and Euglossa securigera) using pollen residue found in brood cells from trap nests installed in an urban fragment in São Luís, Maranhão, Brazil. In 14 analyzed Eg. cordata nests, 23 pollen types were observed, in 7 Eg. townsendi nests, 10 pollen types were observed, and in 1 nest of Eg. securigera, 6 morph types were identified. Solanum (Solanaceae), Zanthoxylum (Rutaceae), Mimosa pudica (Fabaceae), and Chamaecrista (Fabaceae) pollen types were common to all three bee species. Principal components analysis showed 83.04% variability on the first two axes, demonstrating substantial similarity among the samples. Solanum, Mimosa pudica, and Zanthoxylum were the principal components in the ranking. Larger diversity values (mean = 0.80) in some samples indicate that the species gathered resources in a heterogeneous manner; this resembles the findings of other studies of Euglossa. In general, the bees exhibited overlapping niches with regard to the most abundant pollens in the nests, but the females showed individual plasticity when gathering the floral resources.

Do euglossine females reside in a single nest? Notes on Euglossa cordata (Hymenoptera: Apidae: Euglossini)

ABSTRACT Euglossa Latreille, 1802 do not live in large colonies, and these are usually maintained or “reactivated” by new females, subordinate to their mother, which construct and provision brood cells. This study aimed to obtain information about the natural history of Euglossa cordata (Linnaeus, 1758) specially focusing on nest behavior. Our specific objective was to answer the following question: do E. cordata females reside in a single nest? We construct 14 artificial nesting boxes and made them available for E. cordata bees in natural environment for seven months. During this time, we use a re-marking method to identify bee fidelity to a single nest box. More specifically, we record bee permanence in the nests, the time bees take to provision brood to new cells and the time taken to offspring emergence. A total of 12 boxes were colonized by E. cordata and 23 cells were built in an average of 9.78 ± 11 days per cell. Eleven females emerged from the cells in 48.6 ± 11 days. Although adult females moved between nests and sometimes used multiple nests at the same time, E. cordata showed a relatively high fidelity to a single nest (81.1% of the female bees stayed in a single nest more than 50% of time).

Orchid Bees (Hymenoptera: Apidae: Euglossini) in Seasonally Dry Tropical Forest (Caatinga) in Brazil

Euglossini bees are important Neotropical pollinators, but there is a lack in the knowledge about this fauna in dry tropical environments. The aims of this study were to evaluate the richness and abundance of euglossine bees in two fragments of seasonally dry tropical forest (Caatinga), as well as to assess the distribution of euglossine species richness in the Caatinga environment. Males were collected along 12 consecutive months, using traps with aromatic baits. The species richness (S=5) was lower than in rainforests and savannas. Euglossa cordata (L.) was the dominant species in the assemblage, representing 70% of the individuals. The highest abundance occurred in the rainy season. Euglossini fauna presents low local species richness in Caatinga areas, however the beta diversity is higher, since assemblages in different habitats have differences in species composition.

The Orchid Bee Communities in different phytophysiognomies in the Atlantic Forest: from lowland to montane rainforests

To investigate species composition, diversity, richness, and monthly abundance of orchid bees in different types of dense rainforest, placed in different altitudes, the orchid bees were collected for 11 months in three vegetation types: dense montane ombrophilous forest (DMOF), dense submontane ombrophilous forest (DSOF, with two sites points), and dense lowland ombrophilous forest (DLOF). Were collected 1,945 males of 20 species using aromatic traps. The DMOF showed the highest species richness (19), and diversity (H’ = 2.42) , whereas the DSOF_1 showed the highest abundance (775). Euglossa cordata (Linnaeus) was the most abundant species in three areas, and Euglossa ignita Smith was the most abundant species in the DSOF_2 . Abiotic factors were correlated with some community parameters. Our study reveals the importance of preserving different phytophysiognomies within the same biome to conserve orchid bees.