Bees are essential for ecosystem functioning, pollinating many wild and crop plant species. Predicting which species are most vulnerable to global changes, and how their loss may impact ecosystems and human well-being, is critical. Comprehensive information on bee response and effect traits is fundamental to these assessments. However, the Raunkiærian shortfall-insufficient trait data-remains significant for bees, particularly in the Neotropics. Moreover, it remains uncertain whether conservation strategies based on functional diversity from temperate regions can be generalized to the Neotropics. To address this gap, we compiled a comprehensive and validated dataset on Brazilian bee traits, covering 24 traits related to sociality (100% of the species with some information), nesting (88%), body size (71%), and buzzing capacity (42%) on 2,066 Brazilian bee species. The trait data here presented is a crucial resource for evaluating bee species' pollination effectiveness and susceptibility to global change. Comparative analysis with regions with ample trait data-USA, Europe, and China-revealed notable differences. Brazilian bees exhibited a higher prevalence of aboveground nesting species, especially compared to Europe. The proportion of eusocial species was also greater than in Europe and the United States, and more similar to China. Differently from other regions, Brazilian eusocial bees were significantly smaller than their non-eusocial counterparts. These cross-regional comparisons highlight the importance of geographically tailored conservation strategies and underscore the need for extensive trait data to accurately predict regional vulnerabilities and ecological impacts in a rapidly changing world.

The collapse of the Fundão dam in 2015 was Brazil's most serious environmental disaster to date, but its long-term impacts on pollinators are still poorly understood. The Fundão dam was part of the mining company Samarco, and this study evaluated the effects of mining tailings on bee communities along the Rio Doce watershed, comparing Impacted Areas (AI) and Reference Areas (AR) in five regions. The bee survey yielded a sample of 10,721 individuals from 88 species during the dry and rainy seasons. Contrary to the hypothesis of a drastic decline, species richness did not differ significantly between areas (AI = 13.53; AR = 12.40). Bee abundance was significantly higher in impacted areas than in the control, unaffected sites (197.33 vs. 160.06), a pattern driven mainly by collections in the dry season. Statistical modelling revealed that abundance was positively associated with native forest cover and clay soils, but negatively associated with distance from tailings and organic matter. Community composition was strongly shaped by regional environmental filters (R2 = 0.60), while the presence of tailings explained minimal variation (R2 = 0.03). Furthermore, beta diversity was predominantly driven by species replacement (turnover) rather than species loss (nestedness). Our results demonstrate that, at the studied scale, the mining tailings disaster did not negatively affect overall bee richness and composition. Instead, the bee community exhibits resilience, likely sustained by the maintenance of native forest remnants, which act as fundamental environmental filters that provide essential resources. Conservation and restoration efforts should prioritize preserving remnants of native forest and restoring soil physical properties in impacted areas to sustain pollinator diversity in landscapes under mining stress.

Drosophilidae includes well-known species that have served as models in the biological sciences. The family encompasses a wealth of life histories, feeding habits, and morphology. Although Drosophila has been widely used as a model taxon across several disciplines, like taxonomy, systematics, physiology, ecology, and evolutionary biology, way beyond genetics, genomics, and development, significant gaps remain unexplored in the morphological research of these flies. In this paper, we highlight the external and internal skeletal morphology of exemplars of species of Drosophilidae, offering interesting avenues for comparative research, especially to advance fly systematics. We present the first comparative study of two species of Drosophilidae: Drosophila buzzatii (Drosophilinae) and Rhinoleucophenga gigantea (Steganinae). This study provides extensive illustrations of adult males and females using both light microscopy and scanning electron microscopy (SEM), documenting their morphological variations in detail. This work contributes to the interpretation of homology among anatomical structures, standardizes the application of anatomical terms for Drosophilidae, and facilitates communication between studies using drosophilid flies as models.

Supplemental material for 'Comparative skeletal morphology of the bees (Hymenoptera, Apoidea) : a phylogenetic perspective (Bulletin of the American Museum of Natural History, no. 482)' - https://hdl.handle.net/2246/7558

Accurate taxonomic identification is the cornerstone of biodiversity monitoring and agricultural management, particularly for the hyper-diverse superfamily Ichneumonoidea. Comprising the families Ichneumonidae and Braconidae, these parasitoid wasps are ecologically critical for regulating insect populations, yet they remain one of the most taxonomically challenging groups due to their cryptic morphology and vast number of undescribed species. To address the scarcity of robust digital resources for these key groups, we present a curated image dataset designed to advance automated identification systems. The dataset contains 3,556 high-resolution images, primarily focused on Neotropical Ichneumonidae and Braconidae, while also including supplementary families such as Andrenidae, Apidae, Bethylidae, Chrysididae, Colletidae, Halictidae, Megachilidae, Pompilidae, and Vespidae to improve model robustness. Crucially, a subset of 1,739 images is annotated in COCO format, featuring multi-class bounding boxes for the full insect body, wing venation, and scale bars. This resource provides a foundation for developing computer vision models capable of identifying these families.

Understanding the thermal dynamics of stingless bee colonies is essential for developing effective monitoring systems and promoting sustainable meliponiculture. In this study, we compiled and analyzed brood, nest periphery, and ambient temperature data from 36 stingless bee species reported across several published studies. The data were systematized into graphical visualizations, phylogenetic comparative methods, Generalized Least Squares both for heteroscedasticity or autocorrelation in the errors, coefficients of variation (CV), and calculated temperature deltas (ΔT), i.e. the differences between distinct nest zones, to evaluate thermal regulation and summarize temperature patterns across a broad diversity of stingless bees. Our findings show that species with defined brood combs and cerumen envelopes tend to maintain significantly higher and more stable brood temperatures, averaging close to 30 °C, compared to species lacking these structures. Nest temperatures in stingless bees showed a weak but significant phylogenetic signal, indicating partial evolutionary structuring of thermal traits. Yet, the presence of an involucrum was a strong predictor of internal colony temperature, with species constructing this structure maintaining nests approximately 4.8 °C warmer than those lacking it. These results suggest that involucrum construction is a key adaptive trait that largely overrides phylogenetic constraints on thermal regulation. Thermal stability was highest in brood areas (CV = 11.7

Morphology continues to have a central role in systematics and taxonomy, especially regarding the positioning of fossil taxa in the Tree of Life and as an independent source of information to evaluate competing molecular phylogenetic hypotheses. For the stingless bees, morphology and behavior were the only sources of information about their systematics and biogeography for an extended period. Currently, Meliponini is a group with relatively well-known evolutionary relationships in comparison with other bee tribes. However, there are strong incongruences between morphological and molecular results and little progress has been made to reassess the morphological evidence and its role in our understanding of their evolutionary history. Considering this background, the present study intends to take a step further toward understanding the role of morphology in the context of evolutionary relationships among stingless bees. We built a matrix of 375 characters coded for representatives of all extant genera and subgenera of Meliponini. We also included information about the fossil tribe dagger Melikertini and dagger Proplebeia dominicana in parsimony and Bayesian analyses. Results changed according to the optimality criterion and weighting (or partitioning) scheme adopted as well as assumptions regarding outgroups. We demonstrate that the tribe dagger Melikertini, known only from extinct taxa, is strongly supported as the closest relative of the stingless bees. The phylogenetic position of the Miocene fossil dagger Proplebeia dominicana is evaluated and was consistent among all analyses. Morphological evidence shed light on incongruences found in previous phylogenomic analyses, showing that morphology can represent an essential source of evidence to increase our confidence concerning competing hypotheses. A morphological characterization of major clades is provided and synapomorphies are discussed. We argue that combining morphological, chronological, and molecular evidence will be essential for unraveling the complex biogeographic history of stingless bees.

Bees exhibit a remarkable anatomical diversity, with phenotypic traits that reflect broad evolutionary patterns and specific adaptations. Understanding these patterns requires examining key anatomical features, such as thoracic musculature, which drives morpho-functional variation and underscores their extensive phenotypic diversity. The thorax (or ‘mesosoma,’ as it can be referred to in the context of bees and other apocritan Hymenoptera) serves as a power core, housing muscles responsible for leg, wing, and also head and metasomal articulation movements. Despite the role of the thoracic musculature in the flight mechanics of bees, detailed studies are limited to accounts of individual species or small subsets of muscles, with truly comparative analyses being scarce, leaving gaps in understanding muscular variation and phylogenetic significance. To address this, we conducted detailed dissections of 13 species, representing six bee families (Andrenidae, Apidae, Colletidae, Halictidae, Megachilidae, and Melittidae) and three additional apoid wasp taxa (Bembicidae, Crabronidae, Philanthidae), selected to capture a broad range of morphological and phylogenetic diversity. Our results revealed high conservation in mesosomal musculature, with only 16 of 58 muscle groups showing significant variation, primarily in origin points, suggesting a balance between functional constraints and evolutionary flexibility in muscle attachment. Phylogenetically relevant changes were investigated by coding 17 morphological characters, revealing potential synapomorphies for bees or certain lineages. These include the dorsomedial origin of Idlm1 (M. prophragma-occipitalis) in Meliponini, as evident in species such as Melipona quadrifasciata and Tetragonisca fiebrigi, suggesting a shared derived trait for this tribe. Additionally, the extended origin of IIIscm2 is observed in Andrenidae, Colletidae, and Halictidae, indicating closer evolutionary relationships among these families. Bee-specific modifications, including the non-separation of IItpm7b and IItpm7c by the mesepisternal ridge, distinguished bees from most apoid wasps, interpreted here as a potential synapomorphy for bees. Additional variations, such as the ventral origin of Ivlm3 in select lineages and the branched morphology of IIpcm4, suggest independent evolutionary shifts potentially linked to biomechanical demands. These findings underscore the evolutionary stability and phylogenetic value of bee mesosomal musculature, revealing a conserved framework punctuated by lineage-specific adaptations that may correlate with ecological traits.

Bees play an important role as pollinators, and evidence of global bee population declines has become increasingly common. While most studies of plant-pollinator networks focus on contemporary ecosystems, historical interaction datasets remain rare, particularly in tropical regions. Here, we revisited a historical dataset of plant-bee interactions collected between 1971 and 1975 in a cerrado area from southeastern Brazil that was later converted by land-use change. Using this dataset, we described the structure of a historical plant-bee interaction network and examined how bee functional traits, such as body size, social organization, and floral resource use, were associated with species’ topological roles within the network. The network revealed: (i) a core of highly connected bee species, primarily natives; (ii) peripheral bees associated with distinct floral resources; (iii) a highly heterogeneous and compartmentalized organization of interactions; (iv) high interaction specificity; and (v) a weak relationship between bee functional traits and network topological roles. Together, these findings provide a rare descriptive record of a historical cerrado bee-flower visitation network and preserve ecological information from a plant-bee interaction system that can no longer be directly resampled. Historical interaction datasets such as this provide valuable ecological baselines for future comparative studies and can directly support conservation planning, ecological restoration, and biodiversity monitoring. Historical interaction networks help identify key pollinator and plant species that historically contributed to ecosystem organization, provide reference conditions against which restoration success can be evaluated, and contribute to the development of interaction-based indicators of ecosystem functioning. As historical datasets accumulate, they may also become important components of long-term ecological databases supporting conservation policies and restoration planning in highly threatened ecosystems such as the Brazilian Cerrado.

In the published article, Figure 2 was incorrect because the geographic areas of three taxa were shown with errors: the Allodapini (Apidae) occur in the Afrotropical, Australian, Oriental, and Palearctic regions; the Centridini (Apidae) occur in the Nearctic and Neotropical regions; and the Meganomiinae (Melittidae) occur in the Afrotropical and Palearctic regions. The correct figure is included below. We apologize for these errors and thank Dr. Nicolas Vereecken for bringing them to our attention.

ABSTRACT Aim Insect brood parasites (i.e., cleptoparasites), like cuckoo bees, typically attack hosts within specific lineages, but seem to be less constrained by the biogeographical movements of their hosts compared to obligate parasites. Cuckoo bees depend on stable host populations, being particularly sensitive to environmental changes and thus valuable bioindicators of the bee community health. We here test the congruence between the biogeographical history of cuckoo oil bees and their oil bee hosts. Location The Americas. Taxon Bees (Hymenoptera, Apidae). Methods Using phylogenomic and Sanger sequence data, we present new time‐calibrated phylogenies for cuckoo oil bees in the ericrocidine line and their oil bee hosts, Centris and Epicharis. We estimate their ancestral ranges using six historical biogeographical models on a set of 100 trees, randomly sampled from the posterior distribution of phylogenies in each group, thus accounting for uncertainties in divergence time estimates and model selection. Results The origin of the hosts stem in the Cretaceous precedes the origin of their cleptoparasite's stem in the Palaeocene. Cleptoparasite and host crown origins were synchronous in the Eocene, and both took place in tropical South America. While the pair Rhathymini‐ Epicharis remained mostly associated within this region, Centris and their cleptoparasites expanded their distribution to other parts of Neotropical and Nearctic regions in independent range expansions events. In all cases, host range shifts preceded the cleptoparasite shifts. Main Conclusion The biogeographical history of cleptoparasitic oil bees and oil‐collecting hosts is generally congruent in time and space. Events of range expansion mainly occurred in the more species‐rich lineages of cleptoparasites. Range shifts in cleptoparasites followed the distribution of their hosts and coincided with the distribution of oil‐producing plants visited by the host bees. Our results broaden our understanding of the complex biogeography of interacting partners and on how changes in host distributions may impact cleptoparasitic bees.

Diversity can be examined and interpreted from various perspectives, including species richness, genetic and phenotypic differences, variation in behaviors and natural history, and phylogenetic history. Centuries of taxonomic research have revealed approximately 21,000 bee species worldwide. These can be subdivided into a hierarchy of subgroups that reflects their evolutionary history, thanks to the increasingly more comprehensive phylogenetic hypotheses available. Advances in bee systematics have enhanced our understanding of how their diversity has evolved, including their origin in the Cretaceous, shifts in their geographical distribution, the evolution of social and parasitic behaviors, and changes in relationships between bees and the plants they visit throughout a 120-million-year shared evolutionary history. An important outcome of the enduring relationship with flowering plants is the vital role bees play in pollination in both natural and agricultural ecosystems. Habitat loss, climate change, and other anthropogenic environmental alterations have led to declines in bee populations, which have sparked concerns about bee conservation and highlighted the importance of understanding the complementary aspects of diversity, including the evolutionary and geographical components of this variation. The availability of increasingly reliable and comprehensive phylogenetic hypotheses has led to significant advancements, enabling assessments of the phylogenetic diversity of bee communities and predictions regarding their vulnerability to habitat change and their ecological functions. This review explores perspectives of documenting and interpreting bee diversity in a changing world and summarizes the current bee classification while discussing the phylogenetic advances in contemporary research.

Abstract We address an old but still controversial question of morphological phylogenetics: whether additive (or ordered) coding is beneficial to properly extracting phylogenetic information from phenotypical variation. To empirically evaluate the value of the additive coding, we compared the impact of multistate additive, non-additive, and binary codings for 14 quantitative characters in a phylogenetic analysis of a genus of phorid flies (Diptera). First, we compared which of these morphological codings were most effective for the morphological matrix to approximate the results of a molecular data set. We then compared which morphological coding strategies yielded the best Bayesian posterior probabilities when concatenated to molecular data. We also calculated consistency and retention indices for each binary element of the additive characters and contrasted these results to a measure of phylogenetic signal. Overall, these indices were lower for additive characters than for the others but still indicate reasonable accommodation in the tree. Additive coding outperformed the multistate non-additive coding by recovering higher Bayesian posterior probabilities in the concatenated dataset. Additive coding was also among the best coding strategies for the morphological matrix to approximate the phylogenetic signal from an independent source of evidence—i.e., molecular results. Therefore, quantitative information coded as additive had reasonable phylogenetic congruence with other data and improved the phylogenetic results of morphological data in most cases. These results support the use of additive coding for phylogenetic analysis and encourage other similar empirical evaluations aiming to explore the generality of the benefits of this coding method.

The shift to a pollen diet and the evolution of more highly organized societies, i.e., eusocial, were key milestones in bee diversification over their evolutionary history, culminating in a high dependence on feeding broods with a large variety of floral resources. Here, we hypothesized that obligatory eusocial bees have a wider diet diversity than their relatives with solitary lifestyles, and this would be related to colony size. To test both hypotheses, we surveyed diet breadth data (palynological analysis) based on the Shannon-Wiener index (HMODIFIER LETTER PRIME) for 85 bee taxa. We also obtained colony size for 47 eusocial bee species. These data were examined using phylogenetic comparative methods. The results support the generalist strategy as a derived trait for the bee taxa evaluated here. The dietary diversity of eusocial bees (HMODIFIER LETTER PRIME: 2.1, on average) was 67.5% higher than that of noneusocial bees (HMODIFIER LETTER PRIME: 1.21, on average). There was, however, no relationship between diet breadth and colony size, indicating that smaller colonies can harvest a pollen variety as diverse as larger colonies. Taken together, these results provide new insights into the impact of lifestyle on the diversity of collected pollen. Furthermore, this work sheds light on an advantage of living in more highly structured societies irrespective of the size of the colony. Graphical Abstract

Bees are essential pollinators for wild, ornamental, and agricultural plants, but human activities have disrupted their habitats, threatening their persistence. Although bees face numerous challenges in habitats heavily modified by human activities, certain species persist and thrive there. This review synthesizes recent literature on two types of traits that help bees survive in human-modified environments: pre-adaptive traits, which evolved before these environments existed, and adaptive traits, which have evolved in response to new conditions. This review highlights our limited understanding of adaptive traits and examines how trait combinations, including those influenced by epigenetics, contribute to bees' success in these altered habitats. Additionally, we discuss the promising use of genomic tools to reveal signatures of adaptation in these important pollinators.

Fernando A. Silveira had the unique combination of being a sagacious scientist and a remarkable human being. Throughout his career, he made significant contributions to understanding bee diversity and keenly spread this scientific information to the academic community at large and beyond the university walls. His rich character, warm heart, strong voice and laughter are missed by those privileged to be Fernandos students, friends, mentors, and family. In this volume, we honor Fernando A. Silveira, who prematurely passed away at the age of 62, leaving three sons, his wife, and numerous friends.

We present an updated, commented, and revised catalog for the Brazilian cuckoo wasps (Hymenoptera: Chrysididae) and pay tribute to Adolph Ducke's 1913 monographic work on the Brazilian fauna of these wasps titled "As Chrysididas do Brazil." We document all 159 chrysidid species known to occur in Brazil, classified into 18 genera representing three subfamilies: Amiseginae, Chrysidinae, and Cleptinae. We detail all synonyms, provide geographical distribution for all recorded species, and compile host associations for 28 species in Brazil. Notes on type specimens and their depository collections are provided and complemented by images of 30 primary types. Additionally, we reinstated Exsecochrysis Linsenmaier from the synonymy with Pleurochrysis Bohart (rejected junior homonym) in place of Rhipidochrysis Rosa & Pavese, new synonym. All species previously treated as Pleurochrysis are transferred to Exsecochrysis.

The genus Actenosigynes includes two species, A. fulvoniger (Michener, 1989) and A. mantiqueirensis Silveira, 2009, both oligolectic on flowers of Blumenbachia (Loasaceae) in southern Brazil. We describe a third species, Actenosigynes silveirai Siriani-Oliveira, sp. n., and provide additional evidence to the suspected narrow host-plant specificity between bees of this genus and Loasaceae. This new species was only recorded to collect resources on flowers of Aosa, a genus closely related to Blumenbachia in the subfamily Loasoideae. We illustrate female and male specimens of the three species to offer a complete summary of the morphological variation within this modestly sized genus of Neopasiphaeinae, including photographs of male genitalia and associated metasomal sterna. Moreover, we provide an identification key for the three species of Actenosigynes and the first phylogenetic and dating estimate for these taxa. The genus diversified in southern South America during the Miocene-Pliocene, following a more ancient divergence associated with the orogenic events that separated its sister-genus, Torocolletes, west of the Andes. We dedicate this newly described species to Fernando A. Silveira for his contributions to research on Brazilian bee taxonomy and biology.

O objetivo deste capítulo é fornecer as bases para compreender a terminologia de morfologia externa utilizada no restante do livro. Tratamentos extensos da morfologia dos insetos foram apresentados por Snodgrass (1935, 1952), Matsuda (1965, 1970, 1976, 1979), Scudder (1961, 1971), Smith (1969), Tuxen (1970), Denis & Bitsch (1973), Richard & Davis (1977), Bitsch (1979), Nichols (1989), Kukalová-Peck (1991), entre outros. Há inúmeros outros estudos tratando da morfologia de grupos menores, muito valiosos por elucidarem o uso exato de termos entre especialistas de um táxon. Estruturas homólogas podem ser tratadas por nomes diferentes em diferentes ordens de insetos por razões históricas ou pela dificuldade de se estabelecer hipóteses confiáveis de homologia entre as estruturas em grupos diferentes. Ainda, há nomes iguais utilizados, em grupos diferentes, para estruturas não homólogas.

Although the knowledge of the skeletal morphology of bees has progressed enormously, a corresponding advance has not happened for the muscular system. Most of the knowledge about bee musculature was generated over 50 years ago, well before the digital revolution for anatomical imaging, including the application of microcomputed tomography. This technique, in particular, has made it possible to dissect small insects digitally, document anatomy efficiently and in detail, and visualize these data three dimensionally. In this study, we document the skeletomuscular system of a cuckoo bee, Thyreus albomaculatus and, with that, we provide a 3D atlas of bee skeletomuscular anatomy. The results obtained for Thyreus are compared with representatives of two other bee families (Andrenidae and Halictidae), to evaluate the generality of our morphological conclusions. Besides documenting 199 specific muscles in terms of origin, insertion, and structure, we update the interpretation of complex homologies in the maxillolabial complex of bee mouthparts. We also clarify the complicated 3D structure of the cephalic endoskeleton, identifying the tentorial, hypostomal, and postgenal structures and their connecting regions. We describe the anatomy of the medial elevator muscles of the head, precisely identifying their origins and insertions as well as their homologs in other groups of Hymenoptera. We reject the hypothesis that the synapomorphic propodeal triangle of Apoidea is homologous with the metapostnotum, and instead recognize that this is a modification of the third phragma. We recognize two previously undocumented metasomal muscle groups in bees, clarifying the serial skeletomusculature of the metasoma and revealing shortcomings of Snodgrass' "internal-external" terminological system for the abdomen. Finally, we elucidate the muscular structure of the sting apparatus, resolving previously unclear interpretations. The work conducted herein not only provides new insights into bee morphology but also represents a source for future phenomic research on Hymenoptera.