European Bee Research Articles

Thiamethoxam: Long-term effects following honey bee colony-level exposure and implications for risk assessment

Neonicotinoid insecticides have been used in a wide range of crops through seed treatment, soil and foliar applications and a large database exists on both their lethal and sub-lethal effects on honey bees under controlled laboratory conditions. However, colony-level studies on the effects of neonicotinoids in field studies are limited, primarily due to their complexity and the resources required. This paper reports the combined results of two large-scale colony-feeding studies, each with 6 weeks of continuous dosing of 12 colonies per treatment (24 control) to 12.5, 25, 37.5, 50 or 100 ng thiamethoxam/g sucrose solution. Exposure continued beyond dosing with residues present in stored nectar and bee-bread. The studies were conducted in an area with limited alternative forage and colonies were required to forage for pollen and additional nectar The studies provide colony-level endpoints: significant effects (reductions in bees, brood) were observed after exposure to the two highest dose rates, colony loss occurred at the highest dose rate, but colonies were able to recover (2–3 brood cycles after the end of dosing) after dosing with 50 ng thiamethoxam/g sucrose. No significant colony-level effects were observed at lower dose rates. The data reported here support the conclusions of previous colony-level crop-based field studies with thiamethoxam, in which residues in pollen and nectar were an order of magnitude below the colony-level NOEC of 37.5 ng thiamethoxam/g sucrose. The feeding study data are also compared to the outcomes of regulatory Tier 1 risk assessments conducted using guidance provided by the USA, Canada, Brazil and the EU regulatory authorities. We propose an adaptation of the European chronic adult bee risk assessment that takes into account the full dataset generated in laboratory studies while still providing an order of magnitude of safety compared with the colony feeding study NOEC.

Positive effects of the pollinators Osmia cornuta (Megachilidae) and Lucilia sericata (Calliphoridae) on strawberry quality

In the last decades, the fraction of crops requiring biotic pollination has increased dramatically. While wind- and self-pollination is possible for some of these crops, insect pollination generally increases yields and quality of produce. Especially pollinator communities with varying traits often show additive, positive effects on crop pollination. The aim of this study was to investigate the effect of two pollinator species with contrasting life history traits, the European orchard bee, Osmia cornuta, and the green bottle fly, Luciana sericata, on fruit quality, namely size, weight, shape, and color of fruits of the garden strawberry, Fragaria × ananassa We hypothesized that (1) pollination by both species individually results in higher strawberry quality compared to wind- and self-pollination, and (2) combining both species for pollination leads to higher strawberry quality due to higher functional diversity. To test these hypotheses, we used 40 mesh cages, each containing six strawberry plants. Flowering strawberry plants were either exposed to four O. cornuta individuals, four L. sericata individuals, two individuals of each species, or no pollinators (control) for one week. Fruit weight was only significantly higher than the control treatment when strawberry plants were exposed to bees. Fruit deformation, however, significantly decreased with all three pollinator treatments. Strawberry quality in cages with a combination of bees and flies was not superior to strawberry quality in cages with bees alone. Our results highlight the importance of insect pollination for strawberry quality but increased functional diversity of pollinators did not lead to additive pollination effects.

Defense against territorial intrusion is associated with DNA methylation changes in the honey bee brain

BackgroundAggression is influenced by individual variation in temperament as well as behavioral plasticity in response to adversity. DNA methylation is stably maintained over time, but also reversible in response to specific environmental conditions, and may thus be a neuromolecular regulator of both of these processes. A previous study reported DNA methylation differences between aggressive Africanized and gentle European honey bees. We investigated whether threat-induced aggression altered DNA methylation profiles in the honey bee brain in response to a behavioral stimulus (aggression-provoking intruder bee or inert control). We sampled five minutes and two hours after stimulus exposure to examine the effect of time on epigenetic profiles of aggression.ResultsThere were DNA methylation differences between aggressive and control bees for individual cytosine-guanine dinucleotides (CpGs) across the genome. Eighteen individual CpG sites showed significant difference between aggressive and control bees 120 min post stimulus. For clusters of CpGs, we report four genomic regions differentially methylated between aggressive and control bees at the 5-min time point, and 50 regions differentially methylated at the120-minute time point following intruder exposure. Differential methylation occurred at genes involved in neural plasticity, chromatin remodeling and hormone signaling. Additionally, there was a significant overlap of differential methylation with previously published epigenetic differences that distinguish aggressive Africanized and gentle European honey bees, suggesting an evolutionarily conserved use of brain DNA methylation in the regulation of aggression. Lastly, we identified individually statistically suggestive CpGs that as a group were significantly associated with differentially expressed genes underlying aggressive behavior and also co-localize with binding sites of transcription factors involved in neuroplasticity or neurodevelopment.ConclusionsThere were DNA methylation differences in the brain associated with response to an intruder. These differences increased in number a few hours after the initial exposure and overlap with previously reported aggression-associated genes and neurobiologically relevant transcription factor binding sites. Many DNA methylation differences that occurred in association with the expression of aggression in real time also exist between Africanized bees and European bees, suggesting an evolutionarily conserved role for epigenetic regulation in aggressive behavior.

Microbiome Structure Influences Infection by the Parasite Crithidia bombi in Bumble Bees.

Recent declines in bumble bee populations are of great concern and have prompted critical evaluations of the role of pathogen introductions and host resistance in bee health. One factor that may influence host resilience when facing infection is the gut microbiota. Previous experiments with Bombus terrestris, a European bumble bee, showed that the gut microbiota can protect against Crithidia bombi, a widespread trypanosomatid parasite of bumble bees. However, the particular characteristics of the microbiome responsible for this protective effect have thus far eluded identification. Using wild and commercially sourced Bombus impatiens, an important North American pollinator, we conducted cross-wise microbiota transplants to naive hosts of both backgrounds and challenged them with a Crithidia parasite. As with B. terrestris, we find that microbiota-dependent protection against Crithidia operates in B. impatiens Lower Crithidia infection loads were experimentally associated with high microbiome diversity, large gut bacterial populations, and the presence of Apibacter, Lactobacillus Firm-5, and Gilliamella spp. in the gut community. These results indicate that even subtle differences between gut community structures can have a significant impact on a microbiome's ability to defend against parasite infections.IMPORTANCE Many wild bumble bee populations are under threat due to human activity, including through the introduction of pathogens via commercially raised bees. Recently, it was found that the bumble bee gut microbiota can help defend against a common parasite, Crithidia bombi, but the particular factors contributing to this protection are unknown. Using both wild and commercially raised bees, we conducted microbiota transplants to show that microbiome diversity, total gut bacterial load, and the presence of certain core members of the microbiota may all impact bee susceptibility to Crithidia infection. Bee origin (genetic background) was also a factor. Finally, by examining this phenomenon in a previously uninvestigated bee species, our study demonstrates that microbiome-mediated resistance to Crithidia is conserved across multiple bumble bee species. These findings highlight how intricate interactions between hosts, microbiomes, and parasites can have wide-ranging consequences for the health of ecologically important species.

Genetic structure of the bumble bee Bombus hypocrita sapporoensis, a potential domestic pollinator for crops in Japan

The European bumble bee, Bombus terrestris, is an excellent commercial pollinator. In Japan, B. terrestris is categorized as an invasive alien species, and the use of the bee is restricted. In this study, we identify the native bumble bee Bombus hypocrita sapporoensis as a candidate commercial pollinator in Hokkaido Island. To evaluate the risk of disturbing the natural genetic structure if this bee is used as a commercial pollinator, we sequenced the mitochondrial cytochrome c oxidase subunit I (COI) gene to elucidate the phylogenetic relationship of B. h. sapporoensis in Hokkaido Island and the Asian continent. In addition, we analyzed six microsatellites to further investigate the population genetic structure in Hokkaido Island. The mitochondrial analyses revealed that there is little differentiation within Hokkaido Island; however, there is considerable differentiation between Hokkaido and the Asian continent. Microsatellite analyses using STRUCTURE showed that B. h. sapporoensis in Hokkaido was divided into two genetic groups. Individuals belonging to each group were distributed throughout Hokkaido Island, and no clear geographical differentiation was observed. These results indicate that there would be little risk of genetic disturbance if bees from Hokkaido Island were used. However, it would be advisable to avoid importing continental bees as a pollinating insect in Hokkaido Island.

Presence-only modeling is ill-suited for a recent generalist invader, Anthidium manicatum

Anthidium manicatum, the European wool-carder bee, is an invasive species of concern given its worldwide invasion and aggressive behavior towards native pollinators. Predicting habitat suitability for this species is imperative for estimating threat to native species, and predicting future spread. Previous habitat suitability models used bioclimatic variables to make predictions across a broad geographic region, but these showed little utility at predicting risk at the local habitat scale. Therefore, we created a model using environmental inputs that vary across a regional scale (land cover type and percent impervious surface) and focused within a more restricted geographic region, the Northeastern (NE) US. Occurrence records were aggregated from open-sourced data and published records, and maximum entropy methods were used to create the model. We created a second model using bioclimatic variables (temperature and precipitation), to compare utility of both model inputs. We then tested the accuracy of both models by performing weighted random sampling and stratified random sampling across the NE to obtain presence and absence data for A. manicatum. Given previous predictions of widespread habitat suitability, it was surprising that out of 140 sampled locations, A. manicatum were only found at seven. When comparing model accuracy (Cohen’s Kappa), both models showed low accuracy (land scape variables KHAT = 0.023; bioclimatic variables KHAT = −0.094). Models were also not significantly different from each other (Z = 0.548). Therefore, presence-only modeling may not be suitable for this system, either because these variables are not capturing factors restricting A. manicatum’s range, or it is too early in the invasion process. Additional probability sampling is suggested to refine predictive models.

Africanized bees extend their distribution in California.

Africanized honey bees (Apis mellifera) arrived in the western hemisphere in the 1950s and quickly spread north reaching California in the 1990s. These bees are highly defensive and somewhat more difficult to manage for commercial purposes than the European honey bees traditionally kept. The arrival of these bees and their potentially replacing European bees over much of the state is thus of great concern. After a 25 year period of little systematic sampling, a recent small scale study found Africanized honey bees in the Bay Area of California, far north of their last recorded distribution. The purpose of the present study was to expand this study by conducting more intensive sampling of bees from across northern California. We found Africanized honey bees as far north as Napa and Sacramento. We also found Africanized bees in all counties south of these counties. Africanized honey bees were particularly abundant in parts of the central valley and Monterey. This work suggests the northern spread of Africanized honey bees may not have stopped. They may still be moving north at a slow rate, although due to the long gaps in sampling it is currently impossible to tell for certain. Future work should routinely monitor the distribution of these bees to distinguish between these two possibilities.

Toxicity and poisoning symptoms of selected insecticides to honey bees (Apis mellifera mellifera L.)

Bees are potential pollinators of wide variety of crops. The European dark bee, Apis mellifera mellifera (L.) is widely used for crop pollination. However, pesticide usage in modern agriculture has threatened the plant-bee pollinator interaction. There is lack of data regarding lethal time, insecticide concentration and poisoning symptoms, especially for formulated insecticides that are widely used in insect management. This study shows that the intrinsic toxicity of insecticides (LC 50 ) to A. mellifera mellifera (L.) was in the following order: imidacloprid (0.0070) > fipronil (0.0125) > indoxacarb (0.0266)> cypermethrin (0.0370) > dimethoate (0.0385). The lethal time (LT 50 ) values (h) in the ascending order of toxicity of insecticides were as follows: fipronil (6.56), cypermethrin (6.69), dimethoate (8.00), imidacloprid (9.85) and indoxacarb (13.45). Distinct poisoning symptoms observed in A. mellifera mellifera were extended proboscis, expanded wings, unhooked wings, extended legs and twisted bodies, defecation on cage covers, sting in release-out position and anus with excreta. All the tested pesticides are harmful to the honey bee except azadirachtin. The tested pesticides exhibited different poisoning symptoms in bees, which could be useful for beekeepers in identifying the cause of colony mortality. In conclusion, the pesticide toxicological research on bees is an important safety aspect for beneficial organisms. This study reveals a realistic acute toxicity in the field of commonly used insecticides. The information is important for insecticide selection in order to minimize direct killing of foraging honey bees while maintaining effective management of crop pests. https://doi.org/10.2298/ABS170131020P Received: January 31, 2017; Revised: April 26, 2017; Accepted: May 16, 2017; Published online: June 12, 2017 How to cite this article: Pashte VV, Patil CS. Toxicity and poisoning symptoms of selected insecticides to honey bees (Apis mellifera mellifera L.). Arch Biol Sci. 2018;70(1):5-12.

Compte-rendu des captures réalisées de la formation européenne à la détermination des abeilles (COST Super-B Project) dans le Parc national des Calanques

Report of the catches made by the European bee determination training (COST Super-B Project) in the Calanques National Park.

Dimensions of biodiversity loss: Spatial mismatch in land-use impacts on species, functional and phylogenetic diversity of European bees.

AimAgricultural intensification and urbanization are important drivers of biodiversity change in Europe. Different aspects of bee community diversity vary in their sensitivity to these pressures, as well as independently influencing ecosystem service provision (pollination). To obtain a more comprehensive understanding of human impacts on bee diversity across Europe, we assess multiple, complementary indices of diversity.LocationOne Thousand four hundred and forty six sites across Europe.MethodsWe collated data on bee occurrence and abundance from the published literature and supplemented them with the PREDICTS database. Using Rao's Quadratic Entropy, we assessed how species, functional and phylogenetic diversity of 1,446 bee communities respond to land‐use characteristics including land‐use class, cropland intensity, human population density and distance to roads. We combined these models with statistically downscaled estimates of land use in 2005 to estimate and map—at a scale of approximately 1 km2—the losses in diversity relative to semi‐natural/natural baseline (the predicted diversity of an uninhabited grid square, consisting only of semi‐natural/natural vegetation).ResultsWe show that—relative to the predicted local diversity in uninhabited semi‐natural/natural habitat—half of all EU27 countries have lost over 10% of their average local species diversity and two‐thirds of countries have lost over 5% of their average local functional and phylogenetic diversity. All diversity measures were generally lower in pasture and higher‐intensity cropland than in semi‐natural/natural vegetation, but facets of diversity showed less consistent responses to human population density. These differences have led to marked spatial mismatches in losses: losses in phylogenetic diversity were in some areas almost 20 percentage points (pp.) more severe than losses in species diversity, but in other areas losses were almost 40 pp. less severe.Main conclusionsThese results highlight the importance of exploring multiple measures of diversity when prioritizing and evaluating conservation actions, as species‐diverse assemblages may be phylogenetically and functionally impoverished, potentially threatening pollination service provision.

EFFICACY OF STINGLESS BEE LEPIDOTRIGONA TERMINATA AS INSECT POLLINATOR OF F1 HYBRID CUCUMBER

This research aimed to study the efficacy of stingless bee Lepidotrigona terminata as insect pollinator of F1 Hybrid cucumber. The experiments were conducted at experimental farm of the Faculty of Agricultural Technology, Rajamangala University of Technology, Thanyaburi. The experiment was divided into two parts. The first part, efficacy study of stingless bee as insect pollinator of F1 hybrid cucumber was studied. Experimental design used was Randomized Block Design with four treatments and three replications which were opened – pollination, handed – pollination, stingless bee – pollination, and closed – pollination. The results revealed that cucumber fruit sets were found only in opened – pollination and handed – pollination treatments, with 9.33 and 12.66 fruits, respectively. While no fruit set was found in another two treatments which were closed and stingless bee – pollinations. Second, species diversity and numbers of insect pollinators that visited cucumber flowers during 6.00 a.m. – 18.00 p.m. were determined. As a result, four insect species had visited cucumber flower and the most abundant visitor was European bees (Apis mellifera) that had visited, both male and female cucumber flowers at 09.00 a.m.

Collecting and sharing data on bee health: towards a European Bee Partnership

Collecting and sharing data on bee health: towards a European Bee Partnership

The European wool-carder bee (Anthidium manicatum) eavesdrops on plant volatile organic compounds (VOCs) during trichome collection

The plant-pollinator relationship is generally considered mutualistic. This relationship is less clear, however, when pollinators also cause tissue damage. Some Megachilidae bees collect plant material for nests from the plants they pollinate. In this study, we examined the relationship between Anthidium manicatum, the European wool-carder bee, and the source of its preferred nesting material − Stachys byzantina, lamb’s ear. Female A. manicatum use their mandibles to trim trichomes from plants for nesting material (a behaviour dubbed “carding”). Using volatile organic compound (VOC) headspace analysis and behavioural observations, we explored (a) how carding effects S. byzantina and (b) how A. manicatum may choose specific S. byzantina plants. We found that removal of trichomes leads to a dissimilar VOC bouquet compared to intact leaves, with a significant increase in VOC detection following damage. A. manicatum also visit S. byzantina plants with trichomes removed at a greater frequency compared to plants with trichomes intact. Our data suggest that A. manicatum eavesdrop on VOCs produced by damaged plants, leading to more carding damage for individual plants due to increased detectability by A. manicatum. Accordingly, visitation by A. manicatum to S. byzantina may incur both a benefit (pollination) and cost (tissue damage) to the plant.

Assessment of nutritional resources quality from honeybees (<i>Apis mellifera adansonii</i>, L. 1758: Hymenoptera, Apidae) in three beekeeping sites of the Democratic Republic of Congo

Food products from honeybees are commonly used in Africa as in other parts of the world. The composition of bee related food is important for consumers but also to illustrate the feeding quality for the bees. The present study was aimed at assessing the quality of bee bread and honeys for the survival of A. mellifera adansonii , L. 1758 in the DRC. Several environments were selected, namely a rainforest in Kisangani, a savannah in Kavwaya and a restored forest in Mampu. Bee breads were assessed according to their richness in proteins and essential amino acids. Honeys were evaluated considering the water content, the sugar rates, the amount of 5-(hydroxymethyl)-2-furaldehyde (HMF), the acidity (pH) and conductivity. The average content of protein from pollens collected in the DRC was 14.11 ± 5.27%. The protein content was low compared with the food needs of bees (and to the European breeds). No significant difference was observed between Kisangani, Mampu and Kavwaya in terms of protein content of beebread (P ≥ 0.05). The concentrations of ten essential amino acids for bees were within the optimum range of food needs for honeybees (set for European bee races). Beebreads collected in the rainforest of Kisangani were significantly richer in isoleucine, leucine, valine, arginine, lysine and phenylalanine than those from the savannah of Kavwaya. However, beebreads harvested in Kisangani were not significantly different from those from the replanted Mampu forest. The analysis of honey samples revealed that the Congolese honeys had good nutritional quality for bees. Indeed, reducing sugar content of the collected samples ranged from 63.40 to 73.80%, the content of sucrose ranged from 0.30 to 1.90%, the content of water varied from 16.80 to 22.00%, the pH of the analyzed honey samples ranged from 4.22 to 4.53. The average of the electrical conductivity was 47.74 ± 13.93 μS/cm and the concentration of HMF varied from 1.75 to 31.38 mg HMF/kg of honey. The honeys collected in the rainforest of Kisangani were significantly richer in minerals and moisture than those from the savannah of Kavwaya (P <0.05). However, the honeys collected in the last savannah were richer in sucrose and HMF than those collected in the Kisangani rainforest and the restored forest of Mampu (P <0.05). These results would only be applied for the time at which the samples were collected (January-February) but are an interesting data set for further use of bee related product in DRC. Keywords : Apis mellifera adansonii , honey, bee bread, quality, nutrition, bee ecology, DRC.

European bee study fuels debate over pesticide ban.

Neonicotinoids harm domesticated bees and wild cousins in study, but leave some honey bee colonies unaffected.

Camptopoeum (Camptopoeum) baldocki spec. nov., a new panurgine bee species from Portugal and a description of the male of Flavipanurgus fuzetus Patiny (Andrenidae: Panurginae).

Camptopoeum (Camptopoeum) baldocki spec. nov., a new European panurgine bee species is described and diagnosed. It is currently known only from saltmarshes along the southern coast of the central and eastern Algarve, Portugal. Observations and analysis of scopal pollen loads suggest narrow oligolecty on the similarly halophilous Frankenia laevis (Frankeniaceae). In addition, the allotype male of the Portuguese endemic Flavipanurgus fuzetus Patiny is described and the pollen preferences of Flavipanurgus are reviewed with the addition of new data from Portugal. As a genus, Flavipanurgus species appear to be narrowly oligolectic on a range of flowers from the botanical families Caryophyllaceae, Cistaceae and Crassulaceae.

Microsatellite analysis supports the existence of three cryptic species within the bumble bee Bombus lucorum sensu lato

Mitochondrial cytochrome oxidase I (COI) partial sequences are widely used in taxonomy for species identification. Increasingly, these sequence identities are combined with modelling approaches to delineate species. Yet the validity of species delineation based on such DNA ‘barcodes’ is rarely tested and may be called into question by phenomena such as ancestral polymorphisms in DNA sequences, phylogeographic divergence, mitochondrial introgression and hybridization, or distortion of mitochondrial inheritance through such factors as Wolbachia infection. The common and widespread European bumble bee Bombus lucorum s. lato contains three distinct mitochondrial DNA lineages that are assumed to represent three cryptic species, namely Bombus cryptarum, B. lucorum s. str. and B. magnus. To test whether nuclear gene pools of the three putative species were differentiated, we genotyped 304 sympatric members of the lucorum complex (54 B. cryptarum females, 168 B. lucorum s. str. females and 82 B. magnus females, as defined using mtDNA COI haplotypes) from 11 localities spread across the island of Ireland at seven nuclear microsatellite loci. Multilocus genotypes clustered into three discrete groups that largely corresponded to the three mtDNA lineages: B. cryptarum, B. lucorum s. str. and B. magnus. The good fit of mitochondrial haplotype to nuclear (microsatellite) genotypic data supports the view that these three bumble bee taxa are reproductively isolated species, as well as providing a vindication of species identity using so-called DNA barcodes.

Bioprofiling of Salicaceae bud extracts through high-performance thin-layer chromatography hyphenated to biochemical, microbiological and chemical detections

The buds of poplars (Populus L.) and willows (Salix L.), both from the same family (Salicaceae Mirbel), are increasingly used in gemmotherapy and importantly contribute to the production of the physiologically active propolis by European bee Apis mellifera L. In order to study their phenolic profiles, polar extracts of buds from P. nigra L. were compared to those of P. alba L. and S. alba L. through high-performance thin-layer chromatography (HPTLC). Five chemotypical patterns were distinguished after derivatisation with the Natural Product reagent and confirmed by principal component analysis. The HPTLC analysis was directly hyphenated to various microbiological and biochemical assays as well as spectrometric techniques, directly linking to active molecules in the chromatograms. At a glance, polyvalent compounds were evident when all derivatisation and activity assays, to which HPTLC was hyphenated at ease, were combined together. In Populus buds, at least three antimicrobial compound zones were detected using Aliivibrio fischeri and Bacillus subtilis bioassays, and one phyto-œstrogen with the planar yeast œstrogen screen. In all samples, several inhibitors of acetyl- and butyrylcholinesterase and rabbit liver esterase were detected. Hyphenation to high resolution mass spectrometry supported the assignment of bioactive compounds, as shown for chrysin as selective cholinesterase inhibitor as well as caffeic acid and galangin as antimicrobials in P. nigra and P. alba. This fast and cost-efficient method can be appropriately extended and applied to the botanical origin determination and quality control of bud extracts and propolis samples.

Addition to the checklist of IUCN European wild bees (Hymenoptera: Apoidea)

SummaryThe present study is an update to the first Red List of European Bees published in 2014. The additional records are based on (i) comprehensive review of literature; (ii) new data provided by bee specialists in response to the publication of the first Red List; (iii) new developments in taxonomy of European bees including description of new cryptic species; (iv) new specimens from recent field collections. While the first Red List included a list of 1965 wild bee species with 75 genera, we found 86 additional species, while two more genera have been erected (Seladonia and Vestitohalictus), giving an updated total of 2051 species and 77 genera. The authors discuss the artificial framework of the study considered by International Union for Conservation of Nature (IUCN) to produce the first Red List and they propose the more meaningful West Palaearctic biogeographical region. For this whole region, a first estimation gives 3408 wild bee species in 105 genera. The next taxa have been erected from subspecies to species status: Andrena (Euandrena) limosa Warncke, 1969, stat. n., Andrena (Plastandrena) oligotricha Mavromoustakis, 1952, stat. n.

Two commercial formulations of natural compounds for Varroa destructor (Acari: Varroidae) control on Africanized bees under tropical climatic conditions

It is not uncommon for natural pesticide products to perform inconsistently under different test conditions. Because patented treatments based on natural products have not been tested for the control of Varroa destructor on Africanized hybrid bees under tropical climates in field conditions, an experiment comparing the efficacy of two such natural products was performed. Apilife Var® is a product based on thymol, menthol, eucalyptus and camphor, mixed in a matrix of vermiculite. Hive Clean® contains oxalic acid, sucrose, citric acid, formic acid and propolis. Eighteen Jumbo type hives with Africanized hybrid bees of Apis mellifera from the central region of Veracruz, Mexico, were used. A hive was considered as an experimental unit. Hive Clean® and Apilife Var® treatments consisted of 6 hives each, and the control consisted of 3 hives at an apiary at Tejería, Veracruz, Mexico. The experiment took place from October to December 2013, with an average temperature of 28° C. A Mann-Whitney Rank Sum test was used to separate the corrected percentage of fallen varroa. Apilife Var® was significantly more effective (p = 0.002) with a median number of fallen varroa of 95.8% (mean = 95.5%). The results show that Apilife Var® is a product with a considerable acaricide action on varroa infestations, with an even emission of volatiles under a tropical subhumid climate, with no harm to the bee population on the hive. On the other hand, Hive Clean® showed a median percentage of fallen varroa of 19.7% (mean = 16.7%), indicating lower efficacy levels than those reported by European laboratories under temperate climates and with European bees (A. mellifera carnica). Thus, this product may need to be reformulated and re-tested under tropical climate conditions with Africanized bees.