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Pollinator habitat restorations and enhancements are an important approach to mitigate pollinator declines due to habitat loss and other stressors. Foraging resources can be provided by wildflower plantings grown from seed mixes composed of pollinator‐friendly plant species. Despite clear evidence on the benefits of such plantings for bees and other pollinators, there is limited knowledge on how variation in multiple seed mix design parameters affects floral resources over time. Such information is crucial to improve the effectiveness of different habitat applications and to potentially lower seed costs, which remain an impediment to adoption. We conducted an incomplete factorial field experiment to test the impacts of density, diversity, and forb:grass ratio of seed mixes on floral resource availability and phenological coverage of the resulting plantings. We quantified floral area and phenological coverage over the whole blooming season for three consecutive years in replicated plots of wildflower mixes in two regions of the U.S.A, Northern California's Central Valley and Midwestern Tallgrass Prairie. When different seed densities were fully replicated (e.g. within high forb:grass seed ratios in Minnesota, or forb‐only seedings in California), seeding density had no further impact on floral area and floral phenological coverage. [ABSTRACT FROM AUTHOR]

We report the discovery of the first fossil of an Australian species of Pergidae, Baladi warru gen. et sp. n., found at McGraths Flat, a newly discovered Miocene Konservat‐Lagerstätte in central New South Wales. Using morphological data from the well‐preserved fossil, along with a previously published molecular dataset of 59 taxa and a newly generated molecular dataset for 8 taxa, we constructed a data matrix and generated the first chronogram for Pergidae that incorporates internal calibration points. Our data reveal that Baladi warru belongs to the subfamily Perginae and is closely related to the Australian genera Cerealces and Xyloperga (tribe Cerealcini). According to our analysis, the origin of Pergidae appears slightly younger than previously hypothesised; however, additional calibration points are needed for a more detailed age constraint. Furthermore, ancestral character reconstruction indicates four independent adaptations to toxic Myrtaceae as host plants, while biogeographic analyses suggest that sympatry followed by founder events were the primary processes shaping the current disjunct distribution of pergids. Two significant founder events correspond with transitions to utilising Myrtaceae as host plants. With the approval of the Mudgee Local Aboriginal Land Council, Wiradjuri words were used to name the newly described species. ‘Baladi’ means ‘saw’ and ‘warru’ means ‘wasp’. This name honours the Traditional Owners of the lands on which the fossil was collected. [ABSTRACT FROM AUTHOR]

Gardens can benefit pollinators living in surrounding farmland landscapes, but the reason for their value is not clear. Gardens are no different from many semi-natural farmland habitats in terms of the quantity of floral resources (pollen and nectar) they produce, but the timing of their resource supply is very different, which may explain their value. We show that gardens provide 15% of overall annual nectar in farmland landscapes in Southwest UK, but between 50% and 95% during early spring and late summer when farmland supplies are low. Gardens can therefore reduce seasonal nectar gaps experienced by farmland bumblebees. Consistent with this pattern, bumblebee activity increased in gardens relative to farmland during early spring and late summer. An agent-based model reinforces this point, showing that timing, not quantity, of garden nectar supply enhances bumblebee colony growth and survival in farmland. We show that over 90% of farmland in Great Britain is within 1 km of a garden and therefore positive actions by gardeners could have widespread spillover benefits for pollinators across the country. Given the widespread distribution of gardens around the world, we highlight their important interplay with surrounding landscapes for pollinator ecology and conservation. [ABSTRACT FROM AUTHOR]

A study on the pollination of Ophrys fuciflora (Orchidaceae), which is not a native orchid of Japan, was carried out in a botanical garden in Japan, where the flowers attracted the solitary bee, Eucera nipponensis. Six male bees were observed visiting the flowers over a period of 8 h. The pollinia of O. fuciflora became attached to these bees and four were successfully transferred to the stigmas of nearby flowers. The present study verifies that a species of Ophrys can attract pollinators in Japan, which is at least 8,700 km far from their natural habitat. Thus, it is likely that species of Ophrys could potentially extend their distribution by forming new alliances with other species of bees. [ABSTRACT FROM AUTHOR]

Pollination is a key tenet of ecosystem sustainability and food security, but it is threatened by climate change. While many studies investigated the response of plant‐pollination traits to temperature, few attempted multifactorial and integrative approaches with multiple floral traits. We determined which plant‐pollination traits were disrupted by environmental changes and the consequence for plant fitness. We focused on the thermogenic plant, Arum italicum, which relies on floral scent and heat production to attract its pollinators with a deceptive strategy. In a field mesocosm, we measured the response of floral phenology, thermogenesis traits, scent and plant fitness to experimental changes in shade level, water supply and soil temperature. In the laboratory, we exposed plants to extreme heat to determine the thermoregulation ability at high temperatures. Plant fitness decreased dramatically in response to soil warming and the level of shade. While both factors caused a lower number of inflorescences, soil warming was mostly responsible for the crash in number of fruits. The plant traits related to thermogenesis and scent were relatively resilient to the environmental changes in the mesocosm and were unlikely to produce the observed decrease in plant fitness. First, environmental changes only weakly modified the scent composition. Second, the appendix regulated its maximal temperature almost perfectly, while stamen regulated imperfectly. In the laboratory experiment, the appendix maintained a thermal gradient supposedly to improve scent emission while stamen became cooler than ambient air, possibly preventing the pollinators from overheating within the floral chamber. By contrast, the phenology of flowering was drastically modified. Flowers appeared earlier in the season in response to soil warming (by 39 days) or absence of shade (by 19 days). At the daily scale, flowering hour did not change across the season resulting in plants flowering before sunset late in the season and before the pollinator activity window (mostly nocturnal). The strong shift observed in the flowering period may induce a temporal mismatch with this pollinator both early and late in the season when the insects may not be active so early in the spring and during daytime, respectively, thereby altering plant fitness. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Increasing atmospheric CO2 levels change the elemental composition in plants, altering their nutritional quality and affecting consumers and ecosystems. Ecological stoichiometry provides a framework for investigating how CO2-driven nutrient dilution in pollen affects bees by linking changes in pollen chemical element proportions to the nutritional needs of bees. We investigated the consequences of five years of Free Air CO2 Enrichment (FACE) in a mature oak-dominated temperate forest on the elemental composition of English oak (Quercus robur) pollen. We measured the concentrations and proportions of 12 elements (C, N, P, S, K, Na, Ca, Mg, Cu, Zn, Fe, and Mn) in Q. robur pollen-bearing flowers collected from the Birmingham Institute for Forest Research (BIFoR) FACE facility. An elevated CO2 (eCO2) level of 150 ppm above ambient significantly reduced the S, K, and Fe levels and altered the multi-element ratio, with different elements behaving differently. This shift in pollen multi-element composition may have subsequent cascading effects on higher trophic levels. To assess the impact on bees, we calculated the stoichiometric mismatch (a measure of the discrepancy between consumer needs and food quality) for two bee species, Osmia bicornis (red mason bee) and Apis mellifera (honey bee), that consume oak pollen in nature. We observed stoichiometric mismatches for P and S, in pollen under eCO2, which could negatively affect bees. We highlight the need for a comprehensive understanding of the changes in pollen multi-element stoichiometry under eCO2, which leads to nutrient limitations under climate change with consequences for bees. [ABSTRACT FROM AUTHOR]

The Hunt bumble bee, Bombus huntii , is a widely distributed pollinator in western North America. The species produces large colony sizes in captive rearing conditions, experiences low parasite and pathogen loads, and has been demonstrated to be an effective pollinator of tomatoes grown in controlled environment agriculture systems. These desirable traits have galvanized producer efforts to develop commercial Bombus huntii colonies for growers to deliver pollination services to crops. To better understand Bombus huntii biology and support population genetic studies and breeding decisions, we sequenced and assembled the Bombus huntii genome from a single haploid male. High-fidelity sequencing of the entire genome using PacBio, along with HiC sequencing, led to a comprehensive contig assembly of high continuity. This assembly was further organized into a chromosomal arrangement, successfully identifying 18 chromosomes spread across the 317.4 Mb assembly with a BUSCO score indicating 97.6% completeness. Synteny analysis demonstrates shared chromosome number (n = 18) with Bombus terrestris , a species belonging to a different subgenus, matching the expectation that presence of 18 haploid chromosomes is an ancestral trait at least between the subgenera Pyrobombus and Bombus sensu stricto. In conclusion, the assembly outcome, alongside the minimal tissue sampled destructively, showcases efficient techniques for producing a comprehensive, highly contiguous genome. [ABSTRACT FROM AUTHOR]

Landscape heterogeneity may affect components of biodiversity, including pollinators and the ecosystem function they perform. Landscape heterogeneity may also affect pollinator movement and pollen and gene flow. We assessed how changes in landscape compositional heterogeneity generated by agricultural activities affect the pollen transport service provided by insect pollinators. In eleven agricultural fragments with different landscape heterogeneity, we caught pollinators foraging on flowers and extracted their body pollen loads, discriminating among crop, native, and exotic spontaneous plants. At a local scale, the fragments corresponded to 1-ha plots under agricultural management, or to restored plots without agriculture. The landscape heterogeneity of each fragment was characterized using centered circular areas with different diameters (300, 600, and 1000 m). We then calculated the Shannon Diversity Index as a landscape compositional heterogeneity estimator and using the different landscape patches identified (semi-natural pastures, field crops, woodlands, among others). Through generalized linear mixed models, we found that the amount of pollen transported by individual pollinators was positively related with landscape heterogeneity for all pollen grain categories, but the slope exhibiting a notably sharper incline for crop plant species. In addition, crop pollen load carried by individual pollinator was lower than native and exotic spontaneous pollen, highlighting the importance of these species in agroecosystems. Our findings indicate that increasing landscape heterogeneity can enhance pollen transport, especially from crops and exotic plants. However, to ensure the sustainability of pollination services and agroecosystem functions, it is crucial to protect native plant species and encourage their growth on crop edges, thereby improving agroecosystem conservation. [ABSTRACT FROM AUTHOR]

The genus Bombus (bumble bees) includes approximately 265 species, many of which are in decline in North America and Europe. To estimate colony abundance of bumble bees in natural and agricultural habitats, sibship relationships are often reconstructed from genetic data with the assumption that colonies have 1 monandrous queen. However, some species such as the North American common eastern bumble bee (Bombus impatiens Cresson) can display low levels of polyandry, which may bias estimates of colony abundance based on monandrous sibship reconstructions. To accurately quantify rates of polyandry in wild and commercially mated queens of this species, we empirically estimated mating frequencies using a novel statistical model and genotypes from 730 bees. To genotype individuals, we used a highly polymorphic set of microsatellites on colonies established from 20 wild-caught gynes and 10 commercial colonies. We found multiple fathers in 3 of the wild colonies and 3 of the commercial colonies. This resulted in average effective mating frequencies of 1.075 ± 0.18 and 1.154 ± 0.25 for wild and commercial colonies, respectively. These findings agree with previous reports of low rates of polyandry for B. impatiens. Using a large empirical dataset, we demonstrate that assuming monandry for colony abundance estimation in species that violate this assumption results in an overestimation of the number of colonies. Our results emphasize the importance of studying mating frequencies in social species of conservation concern and economic importance for the accuracy of colony abundance estimation and for understanding their ecology and sociobiology. [ABSTRACT FROM AUTHOR]

Backround: In recent years, with the increasing demand for seedless grape varieties that have lower production costs, are disease resistant/tolerant and require less chemical pesticides, the embryo recovery technique has begun to be used more in table grape breeding studies. However, the desired high success rate has not yet been achieved in these studies. Although there are different reasons for this, especially the grape varieties selected for cross-breeding and the timing of transferring the embryos to medium are among the most important reasons. In this study, focusing on these two important factors, the embryos obtained from different hybridization combinations were transferred to agar medium at different weeks for 4 years and the most successful combination and time were determined. In addition, seedless and large berry grape varieties and some seeded varieties that are resistant/tolerant to fungal diseases were selected as parents because they can provide resistance to disease infections in vitro and thus increase the success rate. Results: The results obtained from the study showed that the selected variety and combination significantly affected the success rate in embryo rescue. Especially in combinations with the 'Yalova Seedless' variety as the female parent, more successful results were obtained compared to combinations of other varieties. When 'Yalova Seedless' variety was pollinated with pollen of 'Red Globe', 'Muscat Bailey A' and 'Exalta' varieties, more seedlings were obtained with the help of embryo rescue. The results obtained over four years showed that the best sampling time after pollination was the eighth week and then the seventh week. Conclusions: According to the results obtained, it has been shown that the selected varieties and the sampling time significantly affect the success rate in embryo rescue studies. Therefore, higher success rates can be achieved in comprehensive breeding studies in which they will be included as pollinators, especially in different seeded varieties that are resistant to diseases and have larger berry size. [ABSTRACT FROM AUTHOR]

Summary: A few Capsicum (pepper) species produce yellow‐colored floral nectar, but the chemical identity and biological function of the yellow pigment are unknown.A combination of analytical biochemistry techniques was used to identify the pigment that gives Capsicum baccatum and Capsicum pubescens nectars their yellow color. Microbial growth assays, visual modeling, and honey bee preference tests for artificial nectars containing riboflavin were used to assess potential biological roles for the nectar pigment.High concentrations of riboflavin (vitamin B2) give the nectars their intense yellow color. Nectars containing riboflavin generate reactive oxygen species when exposed to light and reduce microbial growth. Visual modeling also indicates that the yellow color is highly conspicuous to bees within the context of the flower. Lastly, field experiments demonstrate that honey bees prefer artificial nectars containing riboflavin.Some Capsicum nectars contain a yellow‐colored vitamin that appears to play roles in (1) limiting microbial growth, (2) the visual attraction of bees, and (3) as a reward to nectar‐feeding flower visitors (potential pollinators), which is especially interesting since riboflavin is an essential nutrient for brood rearing in insects. These results cumulatively suggest that the riboflavin found in some Capsicum nectars has several functions. [ABSTRACT FROM AUTHOR]

Insect pollinators frequently forage with conspecifics in nature, thus it is important to understand their behavioral responses to the presence of conspecifics on flowers. Plant-pollinator interactions can be influenced by neighboring flowers, and these neighborhood effects can have important implications for plant fitness. Research about neighborhood effects generally tests how plant traits or different plant communities affect plant-pollinator or plant-herbivore interactions. However, neighborhood effects can also be considered from the point of view of an insect pollinator and how the presence of their own conspecifics on plants alters their perceptions of plant quality. We used the Western honey bee, Apis mellifera, to test whether neighborhood effects affect honey bee foraging behavior. In this context, we refer to neighborhood effects as the relative number of bees on neighboring flowers compared to the number of bees on a focal flower. We found that in a floral neighborhood, the relative number of honey bees present on neighboring flowers has a weak effect, such that more bees on neighboring flowers increase the likelihood of visits to a focal flower. Our results suggest that high numbers of bees on neighboring flowers increase the attractiveness of the entire neighborhood and low numbers of bees on the neighboring flowers decrease the attractiveness of the neighborhood, highlighting that bee activity on neighboring flowers may have significant impacts on pollination services. [ABSTRACT FROM AUTHOR]

Bees play an essential role in the sustainability of terrestrial and agricultural ecosystems as pollinators. However, external factors such as pesticides can negatively affect both bees and plants pollinated by bees, as well as human health. Therefore, less toxic or non-toxic plant protection products have become a popular research topic for a sustainable environment. The purpose of this study was to determine the effects of four different commercial products of diatomaceous earth (Bio, Demite, Detech, Detech WP) on workers of Apis mellifera and Bombus terrestris under controlled laboratory conditions. Each diatomaceous earth product was sprayed on the bees as dust particles for 15 seconds at Maximum Field Dose (10 g/m2). While the worker bees in positive control groups (control +) were exposed to flour, those in the negative control groups (control –) were not exposed to any treatment. The highest mortality rates for B. terrestris and A. mellifera were 22% in Detech WP and 16% in Demite, respectively. However, since mortality rates were under 25% for all the tested DE products, they were classified as harmless for both bee species. Additionally, the direct effect of diatomaceous earth products on honey bees and bumble bees was revealed for the first time in this study. [ABSTRACT FROM AUTHOR]

Abstract Backround In recent years, with the increasing demand for seedless grape varieties that have lower production costs, are disease resistant/tolerant and require less chemical pesticides, the embryo recovery technique has begun to be used more in table grape breeding studies. However, the desired high success rate has not yet been achieved in these studies. Although there are different reasons for this, especially the grape varieties selected for cross-breeding and the timing of transferring the embryos to medium are among the most important reasons. In this study, focusing on these two important factors, the embryos obtained from different hybridization combinations were transferred to agar medium at different weeks for 4 years and the most successful combination and time were determined. In addition, seedless and large berry grape varieties and some seeded varieties that are resistant/tolerant to fungal diseases were selected as parents because they can provide resistance to disease infections in vitro and thus increase the success rate. Results The results obtained from the study showed that the selected variety and combination significantly affected the success rate in embryo rescue. Especially in combinations with the ‘Yalova Seedless’ variety as the female parent, more successful results were obtained compared to combinations of other varieties. When ‘Yalova Seedless’ variety was pollinated with pollen of ‘Red Globe’, ‘Muscat Bailey A’ and ‘Exalta’ varieties, more seedlings were obtained with the help of embryo rescue. The results obtained over four years showed that the best sampling time after pollination was the eighth week and then the seventh week. Conclusions According to the results obtained, it has been shown that the selected varieties and the sampling time significantly affect the success rate in embryo rescue studies. Therefore, higher success rates can be achieved in comprehensive breeding studies in which they will be included as pollinators, especially in different seeded varieties that are resistant to diseases and have larger berry size.

The ecological aspects, distribution, and possible conservation of a syrphid hoverfly, Axona chalcopyga (Wiedemann, 1839) is poorly known due to their rare records. Three female individuals of A. chalcopyga were discovered in the Gelam forests of Terengganu state, which is the first record in Peninsular Malaysia. Here, we provided a pictorial description of the female. We also noted the functional role of the hoverfly as a potential pollinator candidate for the Gelam trees by visiting its flowers.

Pollinators face many stressors, including reduced floral diversity. A low-diversity diet can impair organisms’ ability to cope with additional stressors, such as pathogens, by altering the gut microbiome and/or immune function, but these effects are understudied for most pollinators. We investigated the impact of pollen diet diversity on two ecologically and economically important generalist pollinators, the social bumble bee (Bombus impatiens) and the solitary alfalfa leafcutter bee (Megachile rotundata). We experimentally tested the effect of one-, two-, or three-species pollen diets on gut bacterial communities in both species, and the melanization immune response in B. impatiens. Pollen diets included dandelion (Taraxacum officinale), staghorn sumac (Rhus typhina), and hawthorn (Crataegus sp.) alone, each pair-wise combination, or a mix of all three species. We fed bees their diet for 7 days and then dissected out guts and sequenced 16S rRNA gene amplicons to characterize gut bacterial communities. To assess melanization in B. impatiens, we inserted microfilament implants into the bee abdomen and measured melanin deposition on the implant. We found that pollen diet did not influence gut bacterial communities in M. rotundata. In B. impatiens, pollen diet composition, but not diversity, affected gut bacterial richness in older, but not newly-emerged bees. Pollen diet did not affect the melanization response in B. impatiens. Our results suggest that even a monofloral, low-quality pollen diet such as dandelion can support diverse gut bacterial communities in captive-reared adults of these bee species. These findings shed light on the effects of reduced diet diversity on bee health. [ABSTRACT FROM AUTHOR]

Urbanization in tropical landscapes is a complex phenomenon that can lead to community shifts rather than simple species extinction in response to multiple stressors in peri-urban and urban settings. We have investigated the impacts of different stressors along a tropical urban-peri-urban gradient on the bee community, the health of which is a global conservation concern. Several stressors such as increased built-up area, pesticide application and air pollution may effectively regulate bee community composition and corresponding functional diversity along urban-peri urban gradients. We investigated the changes in bee community structure in response to associated stressors in 20 locations including parks and gardens along an urban-peri-urban gradient surrounding the megacity of Kolkata. Bee community structure differed significantly between urban and peri-urban sites with urban sites showing lower value of nestedness. Network analysis also revealed that Apis florea and Lasioglosssum sp. 1 were the most important species in the urban and peri-urban areas respectively, as they had the highest values in bee-site network parameters. Functional diversity increased with urbanization and decreased with pesticide toxicity. Functional redundancy decreased with urbanization. Individual stressors impacted the bee assemblage differentially along the urbanization gradient. SO2 and pesticide toxicity negatively influenced bee abundance and diversity. Urban sites sustained more specialized species and therefore are more vulnerable to shocks while peri-urban sites had a more functionally redundant community making it comparatively more resilient. [ABSTRACT FROM AUTHOR]

We analysed the wild bee community sampled from 1921 to 2018 at a nature preserve in southern Michigan, USA, to study long-term community shifts in a protected area. During an intensive survey in 1972 and 1973, Francis C. Evans detected 135 bee species. In the most recent intensive surveys conducted in 2017 and 2018, we recorded 90 species. Only 58 species were recorded in both sampling periods, indicating a significant shift in the bee community. We found that the bee community diversity, species richness and evenness were all lower in recent samples. Additionally, 64% of the more common species exhibited a more than 30% decline in relative abundance. Neural network analysis of species traits revealed that extirpation from the reserve was most likely for oligolectic ground-nesting bees and kleptoparasitic bees, whereas polylectic cavity-nesting bees were more likely to persist. Having longer phenological ranges also increased the chance of persistence in polylectic species. Further analysis suggests a climate response as bees in the contemporary sampling period had a more southerly overall distribution compared to the historic community. Results exhibit the utility of both long-term data and machine learning in disentangling complex indicators of bee population trajectories. [ABSTRACT FROM AUTHOR]

Development and maintenance of neural architecture supporting learning and memory, as well as active storage of learnt information, are predicted to carry significant energetic costs. Here we explored whether the demands of learning about fitness-relevant stimuli come at a cost to the reproductive success of an insect model. Bumble bee (Bombus spp.) queens found nests alone, and early in the colony cycle must invest simultaneously in learning about rewarding floral resources and colony founding. We exposed queens of Bombus terrestris audax emerging from diapause to a 6-day reversal learning task and compared colony founding success of these individuals to two control groups that did not learn but received equal food. Additionally, we limited carbohydrate intake in half of queens across all treatments. Nutritionally stressed queens had a lower probability of egg laying, delayed nest initiation and lower offspring production compared with nutritionally unrestricted queens, suggesting resource availability at this life cycle stage is crucial to founding successful colonies and population growth. Nevertheless, potential energetic demands of learning did not reduce colony founding success in a laboratory set-up, even in nutritionally stressed groups. Our findings provide a rare real-world test of the costs associated with learning and suggest they do not affect reproductive potential in bumble bee queens. • Development and use of neural architecture carries potential energetic costs. • We test whether such costs compromise reproductive success in bumble bee queens. • The demands of learning did not affect colony founding success, even under stress. • Nutritional stress negatively affected egg laying and offspring production. • Resource-poor environments may affect bumble bee population dynamics. [ABSTRACT FROM AUTHOR]

Osmia excavata is an excellent pollinator in nature and plays a vital role in the conservation of agro-ecosystems and food security. Given the important role of the gut bacterial community in host health and regulation of host growth and development, using 16S rRNA gene sequencing data, the present study explored the composition of the gut bacterial community and its diversity at different life stages (eggs, young larvae, old larvae, young pupae, old pupae, and 1-day-old adults in cocoons) of the solitary bee Osmia excavata. The results showed that the core phyla in the gut of O. excavata at different life stages were Proteobacteria, Firmicutes, Bacteroidota, and Actinobacteriota, and the core genera were Sodalis, Tyzzerella, and Ralstonia. The highest intestinal bacterial diversity was found in the Egg period, and the lowest bacterial alpha diversity was found in the 1-day-old Adult period; the bacterial diversity of O. excavata showed a process of decreasing, as it was growing from the Egg period to the 1-day-old Adult period. Our study found that O. excavata undergoes a significant change in the structure of the gut flora when it grows from the young pupae to old pupae stage, a period of growth that coincides with the process of cocooning and isolation from the external environment after food depletion. This suggests that food and environmental factors are key contributors to the structure of the bacterial community in the gut of solitary bees. [ABSTRACT FROM AUTHOR]

Honey bees are important plant pollinators and honey producers. Contamination of the environment with metals can lead to a decline in honey bee populations. Copper (Cu) and zinc (Zn) salts are commonly used as fungicides and foliar fertilizers. In this study, we investigated the effects of 10-day chronic oral exposure to different concentrations of Cu (CuSO4) and Zn (ZnCl2) on survival and feeding rates of Carniolan honey bees in laboratory conditions. We found that mortality in honey bee workers increased in a concentration-dependent manner and that Cu (lethal concentration [LC50] = 66 mg/l) was more toxic than Zn (LC50 = 144 mg/l). There was no difference in the feeding rate of Cu-treated bees for the different concentrations tested, but the feeding rate decreased with the increase in Zn concentration. To determine feeding preference or avoidance for Cu and Zn, we conducted 2-choice 24-h feeding experiments. We demonstrated that honey bees preferred Zn-containing solutions compared to the control diet. A two-choice experiment with Cu showed a tendency for honey bees to be deterred by Cu at high concentrations; however, it was not statistically significant. In summary, our results suggest that honey bee workers may suffer adverse effects when exposed to ecologically relevant concentrations of Cu and Zn. [ABSTRACT FROM AUTHOR]

Crop pollination and natural biological control provided by beneficial insects have an economic worth of hundreds of billions of dollars annually. Apple and peach production in North Georgia are economically important industries that benefit from these ecological services. Hover flies are dual ecosystem service providers that have been relatively understudied in orchard ecosystems. We investigated the diversity and seasonal activity of hover flies in apple and peach orchards at 2 sites in North Georgia from March to October 2020 and 2021. Bowl traps were used to sample hover flies in orchard edge and interior habitats. The aphidophagous species Toxomerus geminatus (Say) (Diptera: Syrphidae) and Toxomerus marginatus (Say) (Diptera: Syrphidae) comprised 86.6% of the total hover flies collected. Apple orchards yielded the greatest hover fly presence, species richness, and Toxomerus spp. abundance. Hover fly richness and diversity were greatest during postbloom, but Toxomerus spp. abundance was greatest during the bloom period. No differences in presence, richness, diversity, or Toxomerus spp. abundance were found between edge and interior habitats. Toxomerus geminatus and T. marginatus were dominant from March through August, with T. geminatus being more abundant than T. marginatus in March, early April, and August. October sampling produced the greatest hover fly richness. Our results suggest that hover flies are abundant in North Georgia orchards and exhibit substantial spatial and temporal variation in richness and diversity. Expanded studies incorporating additional sampling efforts and methods are needed to further characterize the hover fly fauna and their impact on North Georgia apple and peach orchards. [ABSTRACT FROM AUTHOR]

Recent declines in insect abundances, especially populations of wild pollinators, pose a threat to many natural and agricultural ecosystems. Traditional species monitoring relies on morphological character identification and is inadequate for efficient and standardized surveys. DNA barcoding has become a standard approach for molecular identification of organisms, aiming to overcome the shortcomings of traditional biodiversity monitoring. However, its efficacy depends on the completeness of reference databases. Large DNA barcoding efforts are (almost entirely) lacking in many European countries and such patchy data limit Europe‐wide analyses of precisely how to apply DNA barcoding in wild bee identification. Here, we advance towards an effective molecular identification of European wild bees. We conducted a high‐effort survey of wild bees at the junction of central and southern Europe and DNA barcoded all collected morphospecies. For global analyses, we complemented our DNA barcode dataset with all relevant European species and conducted global analyses of species delimitation, general and genus‐specific barcoding gaps and examined the error rate in DNA data repositories. We found that (i) a sixth of all specimens from Slovenia could not be reliably identified, (ii) species delimitation methods show numerous systematic discrepancies, (iii) there is no general barcoding gap across all bees and (iv) the barcoding gap is genus specific, but only after curating for errors in DNA data repositories. Intense sampling and barcoding efforts in underrepresented regions and strict curation of DNA barcode repositories are needed to enhance the use of DNA barcoding for the identification of wild bees. [ABSTRACT FROM AUTHOR]

After regulation of pesticides, determination of their persistence in the environment is an important indicator of effectiveness of these measures. We quantified concentrations of two types of systemic insecticides, neonicotinoids (imidacloprid, acetamiprid, clothianidin, thiacloprid, and thiamethoxam) and butenolides (flupyradifurone), in off‐crop nontarget media of hummingbird cloacal fluid, honey bee (Apis mellifera) nectar and honey, and wildflowers before and after regulation of imidacloprid on highbush blueberries in Canada in April 2021. We found that mean total pesticide load increased in hummingbird cloacal fluid, nectar, and flower samples following imidacloprid regulation. On average, we did not find evidence of a decrease in imidacloprid concentrations after regulation. However, there were some decreases, some increases, and other cases with no changes in imidacloprid levels depending on the specific media, time point of sampling, and site type. At the same time, we found an overall increase in flupyradifurone, acetamiprid, thiamethoxam, and thiacloprid but no change in clothianidin concentrations. In particular, flupyradifurone concentrations observed in biota sampled near agricultural areas increased twofold in honey bee nectar, sevenfold in hummingbird cloacal fluid, and eightfold in flowers after the 2021 imidacloprid regulation. The highest residue detected was flupyradifurone at 665 ng/mL (parts per billion [ppb]) in honey bee nectar. Mean total pesticide loads were highest in honey samples (84 ± 10 ppb), followed by nectar (56 ± 7 ppb), then hummingbird cloacal fluid (1.8 ± 0.5 ppb), and least, flowers (0.51 ± 0.06 ppb). Our results highlight that limited regulation of imidacloprid does not immediately reduce residue concentrations, while other systemic insecticides, possibly replacement compounds, concurrently increase in wildlife. Environ Toxicol Chem 2024;43:1497–1508. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

We investigated the plant‐pollinator interactions of the Mexican grass‐carrying wasp Isodontia mexicana—native to North America and introduced in Europe in the 1960s—through the use of secondary data from citizen science observations. We applied a novel data exchange workflow from two global citizen science platforms, iNaturalist and Pl@ntNet. Images from iNaturalist of the wasp were used to query the Pl@ntNet application to identify possible plant species present in the pictures. Simultaneously, botanists manually identified the plants at family, genus and species levels and additionally documented flower color and biotic interactions. The goals were to calibrate Pl@ntNet's accuracy in relation to this workflow, update the list of plant species that I. mexicana visits as well as its flower color preferences in its native and introduced ranges. In addition, we investigated the types and corresponding frequencies of other biotic interactions incidentally captured on the citizen scientists' images. Although the list of known host plants could be expanded, identifying the flora from images that predominantly show an insect proved difficult for both experts and the Pl@ntNet app. The workflow performs with a 75% probability of correct identification of the plant at the species level from a score of 0.8, and with over 90% chance of correct family and genus identification from a score of 0.5. Although the number of images above these scores may be limited due to the flower parts present on the pictures, our approach can help to get an overview into species interactions and generate more specific research questions. It could be used as a triaging method to select images for further investigation. Additionally, the manual analysis of the images has shown that the information they contain offers great potential for learning more about the ecology of an introduced species in its new range. [ABSTRACT FROM AUTHOR]

Concerns about competition between pollinators are predicated on the assumption of floral resource limitation. Floral resource limitation, however, is a complex phenomenon involving the interplay of resource production by plants, resource demand by pollinators, and exogenous factors—like weather conditions—that constrain both plants and pollinators. In this study, we examined nectar limitation during the mass flowering of rosaceous fruit trees in early spring. Our study was set in the same region as a previous study that found severe nectar limitation in summer grasslands. We used this seasonal contrast to evaluate two alternative hypotheses concerning the seasonal dynamics of floral resource limitation: either (H1) rates of resource production and consumption are matched through seasonal time to maintain a consistent degree of resource limitation, or (H2) a mismatch of high floral resource production and low pollinator activity in early spring creates a period of relaxed resource limitation that intensifies later in the year. We found generally much lower depletion in our spring study compared to the near 100% depletion found in the summer study, but depletion rates varied markedly through diel time and across sampling days, with afternoon depletion rates sometimes exceeding 80%. In some cases, there were also pronounced differences in depletion rates across simultaneously sampled floral species, indicating different degrees of nectar exploitation. These findings generally support the seasonal mismatch hypothesis (H2) but underscore the complex contingency of nectar depletion. The challenge of future work is to discern how the fluctuation of resource limitation across diel, inter‐diel, and seasonal time scales translates into population‐level outcomes for pollinators. [ABSTRACT FROM AUTHOR]

Summary: Plant pollen is rich in protein, sterols and lipids, providing crucial nutrition for many pollinators. However, we know very little about the quantity, quality and timing of pollen availability in real landscapes, limiting our ability to improve food supply for pollinators.We quantify the floral longevity and pollen production of a whole plant community for the first time, enabling us to calculate daily pollen availability. We combine these data with floral abundance and nectar measures from UK farmland to quantify pollen and nectar production at the landscape scale throughout the year.Pollen and nectar production were significantly correlated at the floral unit, and landscape level. The species providing the highest quantity of pollen on farmland were Salix spp. (38%), Filipendula ulmaria (14%), Rubus fruticosus (10%) and Taraxacum officinale (9%). Hedgerows were the most pollen‐rich habitats, but permanent pasture provided the majority of pollen at the landscape scale, because of its large area. Pollen and nectar were closely associated in their phenology, with both peaking in late April, before declining steeply in June and remaining low throughout the year.Our data provide a starting point for including pollen in floral resource assessments and ensuring the nutritional requirements of pollinators are met in farmland landscapes. [ABSTRACT FROM AUTHOR]

Lamiaceae is a botanical family rich in aromatic species that are in high demand such as basil, lavender, mint, oregano, sage, and thyme. It has great economical, ecological, ethnobotanical, and floristic importance. The aim of this work is to provide an updated view on the aerobiology of species from the family Lamiaceae, with an emphasis on novelties and emerging applications. From the aerobiology point of view, the greatest interest in this botanical family is related to the volatile organic compounds emitted by the plants and, to a much lesser extent, their pollen. Research has shown that the major volatile organic compounds emitted by the plants from this botanical family are monoterpenes and sesquiterpenes. The most important monoterpenes reported across studies include α-pinene, β-pinene, 1,8-cineole, menthol, limonene, and γ-terpinene. Most reports tend to cover species from the subfamily Nepetoideae. Volatile oils are produced by glandular trichomes found on aerial organs. Based on general morphology, two main types are found in the family Lamiaceae, namely peltate and capitate trichomes. As a result of pollinator-mediated transfer of pollen, Lamiaceae species present a reduced number of stamens and quantity of pollen. This might explain the low probability of pollen presence in the air from these species. A preliminary synopsis of the experimental evidence presented in this work suggests that the interplay of the organic particles and molecules released by these plants and their environment could be leveraged for beneficial outcomes in agriculture and landscaping. Emerging reports propose their use for intercropping to ensure the success of fructification, increased yield of entomophilous crops, as well as in sensory gardens due to the therapeutic effect of volatiles. [ABSTRACT FROM AUTHOR]

The global decline of pollinators, particularly insects, underscores the importance of enhanced monitoring of their populations and habitats. However, monitoring some pollinator habitat is challenging due to widespread species distributions and shifts in habitat requirements through seasons and life stages. The monarch butterfly (Danaus plexippus), a migratory insect pollinator that breeds widely throughout North America, presents a unique case study for testing a sampling framework to overcome these challenges. Monarchs exhibit discrete resource needs across life stages (e.g., larval requirement for milkweed, adult requirement for floral nectar), utilizing many land use types across their extensive geographic range during breeding and migration seasons. The Integrated Monarch Monitoring Program (IMMP) uses a standardized protocol with a generalized random tessellation stratified (GRTS) sampling design to gather spatially balanced and ecologically representative information on monarch habitats within the United States. The IMMP is applicable to various land use types and habitats used by breeding monarchs and may be extended to sites outside of the GRTS design to collect data on non-random sites of interest, such as legacy or conservation sites. Additionally, the IMMP's modular design and publicly available training allows for broad participation, including involvement from community scientists. Here, we summarize habitat metrics (milkweed and floral resources) across 1,233 sites covering much of the monarch's breeding range. We examine variation in milkweed density and floral resource availability on probabilistic (random) and non-probabilistic (convenience) samples and among land use types (site types). Additionally, we assess resource availability within core geographies for monarch breeding and migration, specifically within the U.S. Fish and Wildlife Service's Monarch Conservation Units (western, northern, and southern United States). Milkweed density, floral frequency, and floral richness were higher on nonrandom sites and in the North region. Among site types, milkweed density was highest on Rights-of-Way and Unclassified Grassland, while floral frequency was lowest on Rights-of-Way. The IMMP represents the first field-based habitat monitoring program of this scale for monarchs, yielding a robust dataset on monarchs and their habitats across their breeding range and offering a framework for surveying the habitat of insect species with diverse habitat requirements or widespread distributions. [ABSTRACT FROM AUTHOR]

Changes in the timing and duration of life cycles are distinctive fingerprints of environmental change. Yet, the biotic and abiotic cues underpinning phenology and voltinism, i.e., number of generations per year, are poorly understood. Here, I experimentally test how temperature and provision size influence voltinism and survival to emergence in a solitary bee Colletes validus, and how temperature influences voltinism in the brood parasite Tricrania sanguinipennis. Within the same population, univoltine individuals emerge after 1 year (1-year form), whereas semivoltine individuals enter prolonged dormancy and emerge after 2 years (2-year form). I reared field-collected bees under 2 × 2 factorial experiments with cool (18.5 °C ± 0.5 °C) vs. warm (24 °C ± 0.5 °C) temperature treatments (bees and beetles) and no supplement vs. supplemental food treatments (+ 20% ± 5% pollen provision by mass); beetles were reared under temperature treatments only. Cool temperatures consistently increased the proportion of 2-year bees regardless of provision size, a finding that was consistent with three years of field observations. There was a demographic cost to prolonged dormancy in that both 1- and 2-year bees survived to emergence as adults, but survival of 2-year bees was approximately 50% lower than 1-year bees. Two-year beetles were produced under cooler temperatures, but unlike bees, beetles had nearly perfect survival to emergence in all treatments. This experiment advances our mechanistic understanding of the environmental drivers of voltinism in diverse insect taxa and underscores the importance of considering cryptic life stages when interpreting responses to environmental change. [ABSTRACT FROM AUTHOR]

Cities provide opportunities for biodiversity conservation through the design of urban greenspaces as wildlife habitat. A significant proportion of urban public land is narrow linear road verges, though their small size and harsh environmental conditions (e.g. high soil temperatures) may limit their ability to support plants and animals.We worked with a municipal government in a highly urbanised area to test whether conversion of standard road verges (e.g. lawn) to predominantly native understorey plants (forbs, grasses and shrubs) selected for their abilities to tolerate harsh growing conditions and provide habitat increased the abundance and richness of bees, butterflies and birds. We used a before‐after‐control‐impact experiment and characterised temporal dynamics of biodiversity responses 1 year prior to planting and 4 years post‐planting. We also tested whether traits known to influence species responses to urbanisation (body size and feeding specialisation) mediated responses to road verge plantings.Bee species richness and abundance increased at experimental plantings in the first post‐planting year and remained stable thereafter despite fluctuations at control sites. Butterfly abundance but not richness increased, and there was no evidence of bird responses to plantings.Larger bee species, which are known to be most negatively impacted by urbanisation, benefited more from the road verge plantings, while there was no effect of feeding specialisation. Bird and butterfly traits did not mediate responses to plantings.Synthesis and applications. Road verges comprise a significant proportion of urban green spaces, and our results suggest that despite their small sizes and harsh environmental conditions they can provide habitat for bees and to a lesser extent butterflies. We demonstrated that habitat value can be rapidly enhanced by converting standard road verges to native understorey plants and that these benefits may be greatest for the bee species most negatively impacted by urbanisation. Modifications such as additional plant species or wider verges may be required for urban road verges to provide habitat for a greater range of taxa including birds and butterflies. [ABSTRACT FROM AUTHOR]

Pesticide application is used in horticulture to reduce plant damage from organisms such as insects and mites. Systemic insecticides are highly efficacious and readily taken up by plant tissues. However, pesticide-treated plants may impose risks to nontarget insects or other organisms within ecosystems. In this study, insecticide residues in nectar, leaves, and flower petals of the horticulturally significant herbaceous annual snapdragon, Antirrhinum majus (Lamiales: Plantaginaceae), were assessed at two locations over several weeks following foliar and drench treatment with five systemic insecticides. Concentrations of the insecticides were determined by liquid chromatography-mass spectrometry. The independent effects Application Method, Application Rate, and Time were statistically significant among all active ingredients in the three matrices in both sites in California (CA) and New Jersey (NJ). The interaction effects were also generally statistically significant in the CA site but less consistently so in the NJ site, dependent on the active ingredient and matrix. Post hoc analyses found the highest residue concentrations in leaves and the lowest in nectar, a trend generally consistent over time regardless of active ingredient for both the CA and NJ sites. The results of this study are discussed in the context of conserving pollinators and other beneficial insects. It is recommended that similar studies should be implemented in different geographical regions and climates, along with multiyear studies for perennial ornamental plants. [ABSTRACT FROM AUTHOR]

Crithidia mellificae and Lotmaria passim are trypanosomatids that infect honeybees, and many studies suggest that both parasites contribute to the decline in the honeybee population. The Japanese honeybee (Apis cerana japonica) is a native honeybee that inhabits various areas of Japan and is one of the most important pollinators. Both parasites have been well studied in the western honeybee (Apis mellifera) but have been poorly investigated in A. c. japonica. The present study investigated the presence of C. mellificae and L. passim in one feral and six managed A. c. japonica colonies at three different institutes. Five out of seven colonies were polymerase chain reaction‐positive for L. passim (71.4%); however, C. mellificae was not detected. Four of the five colonies were positive in both the midgut and hindgut, but one was positive only in the hindgut. A homology search and phylogenetic tree of the glycosomal glyceraldehyde‐3‐phosphate dehydrogenase (gGAPDH) and cytochrome b (Cytb) genes obtained in this study indicated that the sequences belonged to L. passim. The results of this study emphasize concerns regarding the health of this ecologically important pollinator and the importance of further investigation of the prevalence of L. passim in A. c. japonica in a wider area of Japan. [ABSTRACT FROM AUTHOR]

We located nesting Himalayan giant honey bees, Apis laboriosa, in Thailand for the first time, at the summit of Doi Pha Hom Pok, Chiang Mai Province. Preliminary identification of the bees based on the color of thoracic hairs and the abdomen was confirmed by morphological, morphometric, and genetic analyses. Additionally, those analyses confirmed two recent community science observations posted to iNaturalist. We review morphological characters that enable identification of A. laboriosa. Our discovery extends the range of the species southward ca. 240 km from previously documented locations in southern Yunnan Province, China. This discovery suggests that A. laboriosa is likely to occur in other highland regions of northern Thailand, western Laos, and the Shan Hills of eastern Myanmar. [ABSTRACT FROM AUTHOR]

As the globe gets more urbanised, the question about how natural biodiversity is structured in cities becomes increasingly pertinent. To contribute to an answer, we studied species richness and spatio-temporal structure of bees in a North European metropolitan area. A gradient of 13 sites in the city of Aarhus, Denmark, was censused from April to September 2016. Forty species, i.e. 29 solitary species (40 % of all individuals), ten Bombus species (28 %), and Apis mellifera (32 %), were sampled monthly in pan traps. (i) Information about species traits was extracted from the literature, and trait values were correlated and used to characterize the fauna. Most were soil-nesters, pollen generalists, and common. (ii) Habitat diversity within five concentric circles with trap at the centre and radii from 50 m to 1000 m was related to bee α diversity. The relationship was significant only within 1,000 m for all bees and for bumblebees. Solitary bee diversity was uncorrelated with habitat diversity at all spatial levels. (iii) Spatio-temporal structure was analysed as two networks, one for bees linked to sites, and one for bees linked to months. Link patterns were analysed for levels of nestedness, modularity, and spatio-temporal β diversity. The two networks were weakly and non-significantly nested, but strongly modular, being composed of five and four modules of co-occurring bees, respectively. (iv) Finally, we studied total β diversity, β TOTAL , being the sum of species turnover, β TURN , and species loss/gain or nestedness, β NEST. For both site and season, β TURN was higher than β NEST , and site β TOTAL was higher than season β TOTAL. One reason for this metacommunity structure may be a high spatio-temporal habitat patchiness, sustaining a rich biodiversity. Thus, a few large areas may not compensate for the loss of several small patches. Consequently, establishment of many green, even small habitats is recommended. [ABSTRACT FROM AUTHOR]

Stingless bees are important pollinators in the ecosystem and crop production in most subtropical and tropical regions of the world. However, the global decline of bee populations is a serious concern. Insecticides are considered crucial factors affecting bee survival. In this study, the acute toxicity of selected synthetic insecticides (imidacloprid, profenofos, and lambda-cyhalothrin) on a stingless bee, Tetragonula pagdeni (Schwarz) (Hymenoptera Apidae), was investigated and the LD50 and LC50 determined through topical, oral, and contact exposure under laboratory conditions. The estimated topical LD50 values for imidacloprid, lambda-cyhalothrin, and profenofos were 0.06, 0.53, and 45.39 ng active ingredient (a.i.)/bee, respectively. The corresponding estimated LD50 values from oral bioassays were 0.66, 7.52, and 75.04 ng a.i./bee, and LC50 values for contact exposure were 48.74, 4,339.83, and 3,062.81 ng a.i./cm2. Overall, imidacloprid exhibited the highest toxicity among the evaluated insecticides for all routes of exposure. In addition, insecticide toxicity was higher in the topical bioassay than in oral and contact bioassays. These findings demonstrate that this stingless bee is extremely vulnerable to insecticide use. Therefore, selection of insecticides in pest control programs should consider mitigation of the risk to and detrimental effects on stingless bees. [ABSTRACT FROM AUTHOR]

Context: Land-use change can cause decreases in plant abundance and richness and the replacement of wild plants with domesticated plants. Changes in plant community composition disrupt mutualistic plant-pollinator interactions with ecological consequences for plants and pollinators, and especially for specialists that rely on certain plants. Objectives: We assessed the effects of land-use change and subsequent shifts in plant communities on resource collection and body size for a bee pollinator, Habropoda laboriosa, a purported specialist of blueberries and related Ericaceae plants. Methods: We collected Habropoda laboriosa across a gradient of land use in north-central Florida including agricultural, natural, and urban habitats. We assessed landcover and floral community composition at each site and related these to bee body size (intertegular distance) and resource use (proportion host plant pollen and pollen diversity collected). Results: Host plant pollen collection and bee body size generally responded similarly to the landscape, both increasing with habitats containing host plants (blueberry farms and natural habitat) but decreasing with urban development. However, host pollen collection and bee body size responded in opposite ways to overall cropland in the landscape, with cropland negatively affecting body size despite positively affecting host pollen collection, indicating other factors associated with cropland might drive declines in bee body size. Conclusions: Land-use change can adversely affect bee diet and body size, and changes in diet likely contribute to changes in body size over time. Specialists are particularly at risk for negative impacts of land-use change due to their inability to shift plant hosts. [ABSTRACT FROM AUTHOR]

To better understand how frequently pollinators visit the most popular annuals and the variation among cultivars, we evaluated 3–6 cultivars, each of petunia, impatiens, begonia, geranium, pansy, and New Guinea impatiens. These 6 annuals account for 46.6% of all garden center annual flower sales in the United States. Flower visits by honey bees, bumble bees, syrphids, other Diptera and other Hymenoptera, combined, varied 3 to 10-fold among cultivars within each of the 6 popular annuals. Begonia and impatiens were visited more frequently by pollinators than pansy, petunia, NG impatiens, and geranium. The 4 most visited cultivars, begonia 'Cocktail Brandy', begonia 'Ambassador Rose Blush', impatiens 'Accent Coral', and impatiens 'Super Elfin XP White' attracted as many pollinators as a benchmark annual, marigold 'Alumia Vanilla Cream', considered as moderately attractive to pollinators. Some conclusions from this research may be helpful for homeowners, landscapers, growers, and breeders. First, the most popular annual flowers are not a good choice for the purpose of attracting and supporting pollinators. However, the large variation among cultivars provides an opportunity to select cultivars that are more attractive to pollinators, particularly for begonia and impatiens. If the most pollinator-visited cultivars of begonia and impatiens are labeled and promoted as such, it would be beneficial to pollinators in urban and suburban landscapes in the USA and Europe, where they comprise 10%–20% of all annual flowers purchased from garden centers. [ABSTRACT FROM AUTHOR]

The global insect decline threatens ecosystem functioning because insects provide many essential services, such as pollination or nutrient cycling. Pollution is one of the main drivers of insect decline besides land-use change, global warming, and invasive species. Airborne particulate matter, such as diesel exhaust particles, is ubiquitous in the environment. Their effects on insects are still largely unknown. We provided queens and workers of the bumble bee Bombus terrestris with pollen spiked with diesel exhaust particles at the early colony founding stage and compared the colony development to control colonies. After 10 weeks, we investigated individual and colony-level life history traits. We did not see any effects of pollen spiked with diesel exhaust particles on worker count, brood count, worker size and relative fat body weight. These results indicate no harmful effects of diesel exhaust particles on colony founding in B. terrestris in our single-stressor setup. Our novel approach adds to the understanding of the role that airborne particulate matter plays in the global insect decline and we are looking forward to seeing similar studies with other species and additional stressors, such as heat stress or food shortages. [ABSTRACT FROM AUTHOR]

In social hymenopterans, monandry of the queen is an ancestral trait, and polyandry is a derived trait. Polyandry of the queen is the norm in a limited number of lineages, such as honeybees, leaf-cutting ants, Pogonomyrmex ants, and Vespula wasps, which presumably provide fitness advantages for the whole colony. The queen of the introduced bumblebee, Bombus terrestris, is polyandrous in Japan, whereas it is monandrous in native regions. We hypothesize that polyandry can evolve in a process that avoids the negative impacts of reproductive interference caused by interspecific mating and conducted genetic studies of the invasive species B. terrestris and two native subspecies, Bombus hypocrita sapporoensis and Bombus hypocrita hypocrita, in Japan. Our results revealed that although the native queens of B. hypocrita hypocrita allopatric with B. terrestris were strictly monandrous, the native queens of B. hypocrita sapporoensis sympatric with B. terrestris were polyandrous. These results suggested that the queens of native B. hypocrita sapporoensis do not experience negative impacts on interspecific mating from the invasive B. terrestris. We discuss the possibility that reproductive interference is a driving force in selection for multiple mating through an arms race between sympatric species. [ABSTRACT FROM AUTHOR]

ABSTRACT Given that the Atlantic Forest is one of the most threatened biomes in the world, this study aims to compare alpha and beta diversity of the bee assemblage sampled in a site covered by remnants of the Atlantic Forest, in the municipality of Colombo, Paraná State, with those from ten other sites along the Curitiba Metropolitan Region, previously sampled under similar methodology. Our objective is to analyze if species diversity and composition are influenced by spatial gradients and vegetation cover. The study site’s bee assemblage is composed of 91 species, including Apis mellifera. The assemblage consists of 42 Apinae, 33 Halictinae, eight Megachilinae, five Colletinae, and three Andreninae species. Compared to the other sites, 11 species were sampled exclusively in Colombo, including Bombus brasiliensis Lepeletier, 1836, Centris proxima Friese, 1899, and Trichocerapis mirabilis (Smith, 1865). The most abundant native species were Trigona spinipes (Fabricius, 1793) (204 individuals), Paratrigona subnuda Moure, 1947 (176) and Scaptotrigona bipunctata (Lepeletier, 1836) (113). Despite its high vegetation cover, Colombo exhibited intermediate values of species richness and diversity when compared to other sites, with a high dominance of Meliponini species. The sites could be separated based on beta diversity and the north–south gradient and vegetation cover were significantly related to species composition at this study’s spatial scale. Understanding the regional communities and the factors that influence species composition is essential for planning effective biodiversity conservation actions.

The spread of exotic plant species is a global issue with substantial ecological and economic costs. One factor that can contribute to their capacity to establish and spread beyond their native range is their ability to attract novel pollinators (i.e., pollination flexibility). Humans have contributed to the spread of plant species across different continents, where they may encounter completely different pollinator families or even orders. While interest in exotic plants has grown considerably in recent years, we lack a global assessment of the common pollinator taxa that visit exotic plants, as well as comparisons of pollinator similarity across native and exotic ranges. This systematic review explores the diversity of floral visitors observed at exotic plants worldwide while also assessing whether these plants tend to attract native or exotic animals. We further quantified the taxonomic similarity of floral visitors in the native versus exotic range. Additionally, we tested the hypothesis that floral visitor similarity is negatively correlated with geographic distance. The data compiled in this review show that exotic plants exhibit pollination flexibility at multiple levels. Most floral visitors were bees, but at least 964 animal species (94 families, 12 orders) were found to visit the 201 exotic plant species (59 families, 29 orders) compiled in this review. Such visitors are typically generalists that forage from diverse plant species. Moreover, exotic plants attract both native and exotic floral visitors, however, the proportion of native visits was found to vary by geographic region (highest in Europe, moderate in North America, and lowest in Oceania). Exotic plants generally attract taxonomically similar floral visitors throughout their global distribution, but can attract novel visitors in regions far from their native range, as predicted. This review synthesizes the currently available data and improves our understanding of plant-pollinator interactions at exotic plants, which is important for restricting the spread of invasive plant species and mitigating their negative effects on native biodiversity worldwide.

Stingless bees (Hymenoptera: Meliponini) are pollinators of both cultivated and wild crop plants in the Neotropical region. However, they are susceptible to pesticide exposure during foraging activities. The fungicide fluazinam is commonly applied in bean and sunflower cultivation during the flowering period, posing a potential risk to the stingless bee Partamona helleri, which serves as a pollinator for these crops. In this study, we investigated the impact of acute oral exposure (24 h) fluazinam on the survival, morphology and cell death signaling pathways in the midgut, oxidative stress and behavior of P. helleri worker bees. Worker bees were exposed for 24 h to fluazinam (field concentrations 0.5, 1.5 and 2.5 mg a.i. mL−1), diluted in 50 % honey aqueous solution. After oral exposure, fluazinam did not harm the survival of worker bees. However, sublethal effects were revealed using the highest concentration of fluazinam (2.5 mg a.i. mL−1), particularly a reduction in food consumption, damage in the midgut epithelium, characterized by degeneration of the brush border, an increase in the number and size of cytoplasm vacuoles, condensation of nuclear chromatin, and an increase in the release of cell fragments into the gut lumen. Bees exposed to fluazinam exhibited an increase in cells undergoing autophagy and apoptosis, indicating cell death in the midgut epithelium. Furthermore, the fungicide induced oxidative stress as evidenced by an increase in total antioxidant and catalase enzyme activities, along with a decrease in glutathione S-transferase activity. And finally, fluazinam altered the walking behavior of bees, which could potentially impede their foraging activities. In conclusion, our findings indicate that fluazinam at field concentrations is not lethal for workers P. helleri. Nevertheless, it has side effects on midgut integrity, oxidative stress and worker bee behavior, pointing to potential risks for this pollinator.

Forcipomyia spp. is a pollinator insect on cacao plants that belongs to the Ceratopogonidae Family, Diptera Order. The objectives of this research were to determine the abundance of the insect population of Forcipomyia spp. in Lima Puluh Kota District and to determine the frequency of visits of those insects to cacao flowers. This research was conducted on a small smallholder plantation in Sungai Talang Village, Lima Puluh Kota District. Then, the samples obtained were identified at the Andalas University Laboratory. This research was conducted using a survey method and purposive sampling technique. Five cacao plants were selected in each plot of land, and then three flower beds per plant were selected to bloom. Sampling was carried out by installing yellow sticky traps. The insects obtained were put into a collection bottle filled with 96% alcohol to preserve those insects, and then the abundance of Forcipomyia spp. Insects were calculated. The research results showed that the highest insect abundance was in Jorong Guguak Nunang: 1.260 individuals, then in Jorong Bukik Apik: 1.061 individuals and the lowest was in Jorong Boncah: 1.045 individuals. The highest frequency of visits was in the morning, with an average of 648 individuals/60 minutes. The insect diversity index based on the Shannon-Wienner Diversity Index in Jorong Guguak Nunang was 1,97; in Jorong Boncah, it was 2,21; in Jorong Bukik Apik was 1,88, and all of it is in the medium diversity level category.

Wild bees are important pollinators in the ecosystem, and it is important to monitor their abundance and diversity to characterize and conserve these pollinators. In this study, wild bees were collected from a Maeul-soop in Seocheon-gun, Chungcheongnam-do, Republic of Korea for 2 years from February 2019 to October 2020. From the survey, a total of 3,258 wild bees from 9 families and 57 species were collected over 2 years in the Maeul-soop. The most dominant species was the Andrena kaguya, followed by the Apis mellifera, the Eucera spurcatipes, the Seladonia aeraria, and the Lasioglossum sibiriacum. Monthly changes in the number of species and populations show that the number of species increased from February and peaked in August, and the population peaked in April and then decreased. In addition, in the list of wild bee species collected over the past 2 years, the Apidae was the largest with 16 species, followed by the Halictidae with 13 species and the Megachilidae with nine species. However, although there is only one species of Andrena kaguya in the Andrenidae, its population is 2,084, which is the largest among all wild bees investigated in this study. The results of this study will be useful in understanding the impact of pollinating insects due to climate change in the future.

Tracking insect biodiversity trends and predicting future trajectories is limited by a lack of monitoring data across large spatiotemporal scales. DNA metabarcoding is a time‐ and cost‐efficient method to obtain these data, but has several potential limitations in comparison to traditional morphological approaches. For example, metabarcoding may miss low‐abundance or smaller bodied individuals and is limited to presence/absence information, which may bias estimates of biodiversity and community composition. However, few comparisons of metabarcoding and morphology‐based identification have been made using insects, the by far most diverse animal taxonomic group.Here, we compared terrestrial insect communities identified via morphology versus metabarcoding across four different habitats and three seasons (late spring, mid‐summer and early autumn) during 2019. We compared identified species and community richness, composition and body size, with a focus on key taxonomic groups of bees, true bugs, butterflies and hoverflies.We identified 252 total species, with 54.8% identified by both methods, whereas 21.4% and 19.8% were solely detected with metabarcoding or morphology, respectively. Overall, total community richness, taxonomic composition and community body size were similar between methods. Metabarcoding detection successes declined in low‐abundance and smaller taxa, particularly bees, hoverflies and true bugs; however, species richness of hoverflies and butterflies tended to be higher compared with morphological identification.Our results show that metabarcoding can provide an accurate overview of insect community differences that are comparable to those determined via morphological identification. We recommend that insect monitoring programmes consider incorporating metabarcoding, although future research is needed to overcome some remaining limitations. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms by which wild bees survive in modified landscapes is important for their conservation and management as pollinators. Pollen is a critical resource for the completion of bee life cycles, so we investigated how the pollen loads carried by native bee communities change between natural forests and farms dominated by exotic crops and weeds in an agricultural region of south‐east Australia.We found that individual bees tended to carry higher proportions of exotic pollen on farms compared with forests (after accounting for whether they were captured on exotic or native flowers), and the diversity of pollen carried by bees did not differ significantly between native forest and farm sites or along native forest cover gradients. This suggests that the native bees found on farms, which are predominantly different species compared with those found in native forests, are not disadvantaged by the dominance of exotic plants in these habitats (though impacts on larval nutrition were not investigated).While some native bees carried crop pollen, others almost exclusively carried the pollen of agricultural weeds (e.g., Arctotheca and Brassica species), such that some native bee species may pollinate and benefit from crops, whereas others may only persist on farms if agricultural weeds are tolerated. [ABSTRACT FROM AUTHOR]

The interaction between fig wasps and their host fig trees (Ficus spp.) is a striking example of an obligate pollination mutualism. Male and female fig wasps are confined within their natal patch instead of panmictic; under this circumstance, mating only occurs between individuals of the same patch. This is known as a local mate competition (LMC). It pays foundresses to invest mainly in daughters and to only produce enough sons to ensure that all female offspring can be fertilized, but in nature, pollinating fig wasps may face many problems with host quality, such as limitation of oviposition sites and the nutrition deficiency of the host fig. The sex ratio of wasps can determine the stability of fig–fig wasp mutualistic system and, thus, the stability of other species associated with it. In this study, we controlled the quality of host figs in three ways. The results showed that the host fig age can influence the sex ratio of pollinator offspring, while the foundress numbers and the presence of pollen have no significant effect on it. A compelling explanation for this result is that the sex-dependent mortality occurs. This is a novel finding of how host quality influences the interaction of fig and fig wasps, which can also help us understand the evolution and stability mechanism of this symbiotic system. [ABSTRACT FROM AUTHOR]