Batesian mimicry is a widespread strategy that reduces the risk of predation of a harmless mimic by imitating a harmful model.1 Batesian mimics often vary greatly in how accurately they resemble their models.2 However, disentangling the causes of evolutionary changes in mimetic accuracy, or lack of them, is challenging. The fossil record provides a powerful tool, although it is constrained by the quality of preservation. In particular, fossil records of accurate mimics are exceptionally rare. Here, we describe the first evidence of highly accurate wasp mimicry, in a fossil belonging to diverse group of Batesian mimics: hoverflies (Diptera, Syrphidae). The hoverfly Spilomyia kvaceki sp. nov., from the Early Oligocene (33 mya) deposits in Děčín-Bechlejovice, Czech Republic, exhibits well-preserved color pattern that closely resembles extant wasp mimics. Whether modern wasp genera could have served as its model remains uncertain. However, there is an abundant fossil record of stem-group social wasps (Palaeovespa spp.)3,4,5,6,7 that we propose as suitable models. Notably, two Palaeovespa specimens were found in the same locality as S. kvaceki,8 supporting their co-occurrence. Currently, passerine birds (Passeriformes) are considered the main selecting agent of mimicry of wasps.9 However, passerines were rare in Europe during the Early Oligocene.10 Thus, the agents selecting the earliest known highly accurate mimics of wasps were most likely non-passerines of Coraciimorphae and Apodiformes clades.10,11,12,13 In conclusion, the highly accurate mimicry of wasps originated during or at least persisted through the era of non-passerine dominance in the guild of diurnal flying insectivorous predators in the Northern Hemisphere.

• Klíčová slova
• Europe, Palaeovespa, Spilomyia, Syrphidae, Vespidae, color pattern, evolution, fossil, mimetic accuracy, perfect mimicry,
• MeSH
• biologická evoluce * MeSH
• Diptera * fyziologie   anatomie a histologie   MeSH
• mimikry * MeSH
• ptáci * fyziologie   MeSH
• sršňovití * fyziologie   anatomie a histologie   MeSH
• zkameněliny * anatomie a histologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

During parasitoid wasp infection, activated immune cells of Drosophila melanogaster larvae release adenosine to conserve nutrients for immune response. S-adenosylmethionine (SAM) is a methyl group donor for most methylations in the cell and is synthesized from methionine and ATP. After methylation, SAM is converted to S-adenosylhomocysteine, which is further metabolized to adenosine and homocysteine. Here, we show that the SAM transmethylation pathway is up-regulated during immune cell activation and that the adenosine produced by this pathway in immune cells acts as a systemic signal to delay Drosophila larval development and ensure sufficient nutrient supply to the immune system. We further show that the up-regulation of the SAM transmethylation pathway and the efficiency of the immune response also depend on the recycling of adenosine back to ATP by adenosine kinase and adenylate kinase. We therefore hypothesize that adenosine may act as a sensitive sensor of the balance between cell activity, represented by the sum of methylation events in the cell, and nutrient supply. If the supply of nutrients is insufficient for a given activity, adenosine may not be effectively recycled back into ATP and may be pushed out of the cell to serve as a signal to demand more nutrients.

When confronted with an infection, immune cells are rapidly activated to fight the threat. However, like all cells, they require energy to act. While most cells reduce their activity when nutrients are scarce, the immune system cannot afford to do so, as halting its response could put the entire body at risk from infection. It is not clear how immune cells manage this complex nutritional budgeting. Previous studies of fruit fly larvae infected with a parasitoid wasp revealed that immune cells secure extra energy by releasing a molecule called adenosine. This slows the metabolism of non-immune tissues, leaving more nutrients available for immune cells. However, the exact mechanism that immune cells use to produce adenosine remained uncertain. To further examine this process, Nedbalova et al. – who are part of the research group that carried out the previous work – extracted activated immune cells from a parasitoid-infected larva and fed them a labelled amino acid. Tracing this label revealed an increase in the number of chemical units known as methyl groups that had been added to molecules within the cell. This process, known as methylation, can regulate metabolic activity within cells and produces adenosine as a byproduct. Further genetic studies showed that if nutrient supplies were sufficient, the immune cells recycled this adenosine back into ATP, the body’s main energy currency. This suggests that if there were not enough nutrients to do this, the excess adenosine would slow the metabolism of non-immune cells, therefore securing more nutrients for the immune cells. Therefore, Nedbalova et al. hypothesise that these two processes could form the basis of a feedback mechanism that allows the immune cells to regulate their energy demands. Taken together, the findings suggest that adenosine may act as a sensor to reflect immune activity, with it being released when the cells are stimulated and recycled if they have enough energy. This hypothesis still requires further testing but, as adenosine pathways are present across all organisms, it could have implications for many physiological and disease-related processes.

• Klíčová slova
• D. melanogaster, S-adenosylhomocysteinase, SAM transmethylation pathway, adenosine kinase, adenosine signaling, adenylate kinase, biochemistry, chemical biology, immunology, inflammation, privileged immunity,
• MeSH
• adenosin * metabolismus   MeSH
• adenosinkinasa metabolismus   MeSH
• adenosintrifosfát * metabolismus   MeSH
• Drosophila melanogaster * imunologie   parazitologie   metabolismus   růst a vývoj   MeSH
• larva imunologie   metabolismus   parazitologie   růst a vývoj   MeSH
• metylace MeSH
• S-adenosylmethionin * metabolismus   MeSH
• sršňovití MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adenosin * MeSH
• adenosinkinasa MeSH
• adenosintrifosfát * MeSH
• S-adenosylmethionin * MeSH

Bee health is influenced by multiple factors, including nutrition, immunity, and parasitic pressures. Since the spread of Varroa destructor, overwintering survival has significantly declined, making it one of the most serious threats to honey bee (Apis mellifera L.) populations worldwide. Natural acaricides, such as oxalic acid (OA), are widely employed for managing Varroa mites; however, their pharmacodynamics, particularly their impacts on honey bee physiology and immunity, remain insufficiently understood. We studied effects of oxalic acid on honey bee workers. The study compared three treatments: flumethrin, OA-glycerine strips (OA-G), and OA trickling (OA-T). Twelve colonies were divided into four groups, with samples collected at five time points (0, 24, 48, 72, and 192 h). Physiological changes were assessed through markers of oxidative stress, longevity, and immune parameters. Exposure to oxalic acid via glycerine strips induced a humoral immune response in adult bees. The antimicrobial activity of hemolymph and levels of antimicrobial peptides (abaecin, apidaecin, defensin, and hymenoptaecin) were elevated between 48 and 192 h after OA-G treatment compared to the control group. In contrast, these parameters were not influenced by OA-T or flumethrin treatment. These findings suggest that OA-G strips activate the honey bee's immune system, providing insights into broader implications of OA use in beekeeping. It is crucial to determine whether the activation of humoral immune systems has positive or negative effects, as well as to develop standardized and reliable treatment protocols that ensure both - health of colonies and their effectiveness in controlling Varroa mite infestations.

• Klíčová slova
• Beekeeping, Integrated Pest management, Oxalic acid, Pharmacodynamics, Treatment, Varroa,
• MeSH
• akaricidy farmakologie   MeSH
• antiinfekční látky farmakologie   MeSH
• glycerol * farmakologie   MeSH
• hemolymfa účinky léků   MeSH
• kyselina oxalová * farmakologie   MeSH
• oxidační stres účinky léků   MeSH
• včely imunologie   účinky léků   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• akaricidy MeSH
• antiinfekční látky MeSH
• glycerol * MeSH
• kyselina oxalová * MeSH

One of the most remarkable examples of Batesian mimicry occurs in the genus Temnostoma Le Peletier & Audinet-Serville, 1828 (Diptera: Syrphidae). Adults of this genus have an overall resemblance to hymenopterans combined with behavioural mimicry (they move the fore legs in front of the head mimicking hymenopteran antennae). While some species of Temnostoma are considered highly accurate mimics of social wasps, other species have a darker colour pattern and are rather relatively poor yellowjacket mimics. Both colour phenotypes are widespread through the Holarctic. Here, we infer for the first time the evolutionary history of the genus with special focus on the evolution of mimicry and biogeography. With material covering 75 % of known species of Temnostoma and both colour phenotypes from each biogeographical region, we inferred a molecular phylogeny based on six molecular markers (mitochondrial protein-coding COI gene, nuclear 28 s rRNA gene, and four nuclear protein-coding genes: AATS, CK1, TULP, and RBP-15). Using Bayesian inference, we obtained a highly resolved phylogenetic tree supporting the monophyly of the genus Temnostoma as a sister group of genus Takaomyia Hervé-Bazin, 1914. Within Temnostoma, Te. daochus and Te. barberi (two Nearctic species with strikingly different mimicry patterns) were found to be closely related to each other and together form a lineage sister to the rest of the genus. Our results suggest that the behavioural mimicry of wasp antennae is a plesiomorphic state inherited from a common ancestor that includes the genera Temnostoma and Takaomyia. Within Temnostoma, the dark colour pattern (poor yellowjacket mimicry) appears to be an ancestral state and highly accurate social wasp mimicry has appeared two times independently within the genus. In some species inhabiting northern parts of the Holarctic, secondary darkening and consequent degradation of the yellowjacket mimicry appeared. This indicates high evolutionary plasticity and ongoing selection pressure on morphological characters related to mimicry in hover flies.

• Klíčová slova
• Batesian mimicry, Flower flies, Hover flies, Hoverflies, Molecular phylogeny, imperfect mimicry, perfect mimicry,
• MeSH
• Bayesova věta * MeSH
• biologická evoluce MeSH
• Diptera genetika   klasifikace   anatomie a histologie   MeSH
• fenotyp MeSH
• fylogeneze * MeSH
• fylogeografie MeSH
• mimikry * genetika   MeSH
• sekvenční analýza DNA MeSH
• sršňovití * genetika   klasifikace   anatomie a histologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The honeybee (Apis mellifera) is a key pollinator critical to global agriculture, facing threats from various stressors, including the ectoparasitic Varroa mite (Varroa destructor). Previous studies have identified shared bacteria between Varroa mites and honeybees, yet it remains unclear if these bacteria assemble similarly in both species. This study builds on existing knowledge by investigating co-occurrence patterns in the microbiomes of both Varroa mites and honeybees, shedding light on potential interactions. Leveraging 16S rRNA datasets, we conducted co-occurrence network analyses, explored Core Association Networks (CAN) and assess network robustness. Comparative network analyses revealed structural differences between honeybee and mite microbiomes, along with shared core features and microbial motifs. The mite network exhibited lower robustness, suggesting less resistance to taxa extension compared to honeybees. Furthermore, analyses of predicted functional profiling and taxa contribution revealed that common central pathways in the metabolic networks have different taxa contributing to Varroa mites and honeybee microbiomes. The results show that while both microbial systems exhibit functional redundancy, in which different taxa contribute to the functional stability and resilience of the ecosystem, there is evidence for niche specialization resulting in unique contributions to specific pathways in each part of this host-parasite system. The specificity of taxa contribution to key pathways offers targeted approaches to Varroa microbiome management and preserving honeybee microbiome. Our findings provide valuable insights into microbial interactions, aiding farmers and beekeepers in maintaining healthy and resilient bee colonies amid increasing Varroa mite infestations.

• Klíčová slova
• Apis mellifera, Varroa destructor, Community assembly, Microbiomes, Networks,
• MeSH
• Bacteria * klasifikace   genetika   izolace a purifikace   MeSH
• mikrobiota * MeSH
• RNA ribozomální 16S genetika   MeSH
• Varroidae * mikrobiologie   MeSH
• včely mikrobiologie   parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• RNA ribozomální 16S MeSH

The recent popularity of indoor farming has brought about problems with parasites spreading among pollinator colonies. The natural product callunene (1) can be used in the prophylaxis of bumblebees against Crithidia infection. Here, we report the synthesis of callunene (1), its enantioseparation, and a method for analyzing its optical purity. The approach was applied to determine the configuration of callunene extracted from heather honey. The proposed method is also applicable to the analysis of mixtures of diastereomers obtained during callunene synthesis, which allows the stereospecificity of individual reaction steps to be determined.

• MeSH
• antiparazitární látky chemie   farmakologie   MeSH
• biologické přípravky * chemie   MeSH
• med analýza   MeSH
• molekulární struktura MeSH
• stereoizomerie MeSH
• včely MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antiparazitární látky MeSH
• biologické přípravky * MeSH

Background/Objectives: The increasing pressure from pathogens and parasites on Apis mellifera populations is resulting in significant colony losses. It is desirable to identify resistance-associated single-nucleotide polymorphisms (SNPs) and their variability for the purpose of breeding resilient honeybee lines. This study examined the genetic diversity of 13 SNPs previously studied for associations with various resistance-providing traits, including six linked to Varroa-specific hygiene, five linked to suppressed mite reproduction, one linked to immune response, and one linked to chalkbrood resistance. Methods: Genotyping was performed using a novel SNaPshot genotyping panel designed for this study. The sample pool consisted of 308 honeybee samples in total, covering all 77 administrative districts of the Czech Republic. Results: All examined loci were polymorphic. The frequency of positive alleles in our population is medium to low, depending on the specific SNP. An analysis of genotype frequencies revealed that most loci exhibited the Hardy-Weinberg equilibrium. A comparison of the allele and genotype frequencies of the same locus between samples from hives and samples from flowers revealed no significant differences. The genetic diversity, as indicated by the heterozygosity values, ranged from 0.05 to 0.50. The fixation index (F) was, on average, close to zero, indicating minimal influence of inbreeding or non-random mating on the genetic structure of the analyzed samples. Conclusions: The obtained results provide further insights into the genetic variation of SNPs associated with the immune response and resistance to pathogens in honeybee populations in the Czech Republic. This research provides a valuable foundation for future studies of honeybee diversity and breeding.

• Klíčová slova
• Apis mellifera, SMR, SNP, VSH, Varroa resistance, genetic diversity, hygienic behavior, immune response,
• MeSH
• frekvence genu MeSH
• genetická variace MeSH
• genotyp MeSH
• genotypizační techniky metody   MeSH
• jednonukleotidový polymorfismus * MeSH
• odolnost vůči nemocem * genetika   MeSH
• včely genetika   imunologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

Facultative symbionts are widespread in arthropods and can provide important services such as protection from natural enemies. Yet what shapes associations with defensive symbionts in nature remains unclear. Two hypotheses suggest that interactions with either antagonists or host plants explain the prevalence of symbionts through shared selective pressures or vectors of symbiont transmission. Here we investigate the factors determining similarities in the Hamiltonella defensa symbiosis shared amongst field-collected aphid species. After accounting for host species relatedness, we find that Hamiltonella's genotype distribution aligns with sharing the same parasitoids, rather than host plants, highlighting parasitoids and hosts as key selective agents shaping the symbiosis across aphid species. Our data indicates parasitoid host specificity drives the prevalence of specific aphid-Hamiltonella associations, suggesting defensive symbioses are maintained by the selective pressure imposed by dominant parasitoids and their aphid hosts. These findings underscore the importance of interactions with natural enemies in explaining patterns of defensive symbiosis in nature.

• Klíčová slova
• Hamiltonella defensa, defensive symbiosis, facultative symbionts, horizontal transmission, host‐parasitoid networks, insect ecology,
• MeSH
• Enterobacteriaceae genetika   fyziologie   MeSH
• genotyp * MeSH
• interakce hostitele a parazita * MeSH
• mšice * parazitologie   fyziologie   MeSH
• sršňovití * fyziologie   genetika   MeSH
• symbióza * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• dopisy MeSH

Lotmaria passim is a ubiquitous trypanosomatid parasite of honey bees nestled within the medically important subfamily Leishmaniinae. Although this parasite is associated with honey bee colony losses, the original draft genome-which was completed before its differentiation from the closely related Crithidia mellificae-has remained the reference for this species despite lacking improvements from newer methodologies. Here, we report the updated sequencing, assembly, and annotation of the BRL-type (Bee Research Laboratory) strain (ATCC PRA-422) of Lotmaria passim. The nuclear genome assembly has been resolved into 31 complete chromosomes and is paired with an assembled kinetoplast genome consisting of a maxicircle and 30 minicircle sequences. The assembly spans 33.7 Mb and contains very little repetitive content, from which our annotation of both the nuclear assembly and kinetoplast predicted 10,288 protein-coding genes. Analyses of the assembly revealed evidence of a recent chromosomal duplication event within chromosomes 5 and 6 and provided evidence for a high level of aneuploidy in this species, mirroring the genomic flexibility employed by other trypanosomatids as a means of adaptation to different environments. This high-quality reference can therefore provide insights into adaptations of trypanosomatids to the thermally regulated, acidic, and phytochemically rich honey bee hindgut niche, which offers parallels to the challenges faced by other Leishmaniinae during the challenges they undergo within insect vectors, during infection of mammals, and exposure to antiparasitic drugs throughout their multi-host life cycles. This reference will also facilitate investigations of strain-specific genomic polymorphisms, their role in pathogenicity, and the development of treatments for pollinator infection.

• Klíčová slova
• Lotmaria passim strain BRL, ATCC PRA-422, Hi-C, Leishmaniinae, PacBio, Trypanosomatidae, aneuploidy, monoxenous, polyploidy, trypanosomatid,
• MeSH
• anotace sekvence MeSH
• fylogeneze MeSH
• genom protozoální MeSH
• genomika metody   MeSH
• molekulární evoluce * MeSH
• Trypanosomatina * genetika   klasifikace   MeSH
• včely parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Forecasting insect responses to environmental variables at local and global spatial scales remains a crucial task in Ecology. However, predicting future responses requires long-term datasets, which are rarely available for insects, especially in the tropics. From 2002 to 2017, we recorded male ant incidence of 155 ant species at ten malaise traps on the 50-ha ForestGEO plot in Barro Colorado Island. In this Panamanian tropical rainforest, traps were deployed for two weeks during the wet and dry seasons. Short-term changes in the timing of male flying activity were pronounced, and compositionally distinct assemblages flew during the wet and dry seasons. Notably, the composition of these distinct flying assemblages oscillated in consistent 4-year cycles but did not change during the 16-year study period. Across time, a Seasonal Auto-Regressive Integrated Moving Average model explained 75% of long-term variability in male ant production (i.e., the summed incidence of male species across traps), which responded negatively to monthly maximum temperature, and positively to sea surface temperature, a surrogate for El Niño Southern Oscillation (ENSO) events. Establishing these relationships allowed us to forecast ant production until 2022 when year-long local climate variables were available. Consistent with the data, the forecast indicated no significant changes in long-term temporal trends of male ant production. However, simulations of different scenarios of climate variables found that strong ENSO events and maximum temperature impacted male ant production positively and negatively, respectively. Our results highlight the dependence of ant male production on both short- and long-term temperature changes, which is critical under current global warming.

• Klíčová slova
• Ant reproduction, Barro Colorado Island, Climate change, El Niño Southern Oscillation, Formicidae, Seasonal auto-regressive integrated moving average with exogenous factors, Time-series, Tropical forests,
• MeSH
• deštný prales MeSH
• ENSO MeSH
• Formicidae * fyziologie   MeSH
• klimatické změny MeSH
• roční období * MeSH
• teplota MeSH
• tropické klima * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH