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Trapping trichomes, a common trait found in protogynous trap flowers, are thought to enable interaction with pollinators, promoting both pollen removal and fruit set. However, this hypothesis has yet to be empirically confirmed.In this study, we experimentally tested whether trapping trichomes favour male and female functions in trap flowers. Using protogynous South American Aristolochia esperanzae trap flowers, we observed the temporal variation in both sexual functions and associated them with the wilting of the flower and trapping trichomes. Next, we described the trapping trichomes features associated with the capture, entrapment and release of pollinators. Finally, we used manipulative experiments involving trapping trichome removal to quantify their influence on pollinator entrapment, pollen removal and fruit set.While flowers wilted after the end of the female phase, the trapping trichomes only wilted some hours after pollen presentation, promoting a delay in the exit of pollinators, so they carried pollen. Trapping trichomes features, such as a density gradient towards the interior of the tube, unidirectional orientation and epicuticular waxes, may be important in the capture and entrapment of pollinators. Trapping trichome removal decreased drastically the probability of pollinator entrapment and pollen removal, leading to no fruit set.These results indicate that the evolution and maintenance of trapping trichomes in trap flowers probably occurred through selective pressures from both sexual functions and highlight their role in the functioning of this highly phenotypically specialized pollination system. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Onion thrips (Thrips tabaci) are a major pest of onion crops, but they can be controlled using syrphid larvae, which are omnivorous, as biological control agents. The introduction of secondary plants may enhance syrphid activity and contribute to the suppression of onion thrips population in onion–barley intercropped fields. Therefore, two experiments were conducted to evaluate the effect of introducing secondary plants on the population of onion thrips and the occurrence of syrphids in onion–barley intercropped fields. In the first 2-year experiment, buckwheat, lacy phacelia, and coriander planted around barley-intercropped onion fields did not result in a significant reduction in the number of onion thrips. However, in the second experiment, which employed mixed intercropping of barley and buckwheat, significantly greater suppression of onion thrips population was observed in the mixed intercropping plots than in plots containing only barley intercropping. In addition, the number of syrphid eggs on intercropped barley was significantly higher in the mixed intercropping plots than in plots containing barley alone, demonstrating that planting flowering plants near barley can attract hoverflies and increase oviposition on barley. Furthermore, three-year experiments revealed more syrphid larvae on onion plants than on barley, with eggs found only on barley. These findings indicate that hoverflies oviposit on intercropped barley; then, the hatched larvae move to onion plants to prey on onion thrips. Overall, this study offers great insights into the potential use of intercropping with flowering plants to boost natural biological control of onion thrips, providing implications for sustainable pest management in onion production. [ABSTRACT FROM AUTHOR]

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Pesticides and the lack of floral resources are key drivers of insect decline in agricultural areas. Both land‐use stressors can have a variety of synergistic and sublethal effects on pollinators, affecting their health and foraging behaviour. Pollinating insects include species with vastly different life histories, giving them potentially different vulnerability and resilience to stressors. However, most research has generally focused on bees. Here, we contrast synergistic effects of nutritional stress and pesticide use on social bumblebees and solitary hoverflies. We experimentally tested the effects of the neonicotinoid acetamiprid and low‐quality food on health traits of Bombus terrestris workers and Episyrphus balteatus adults (ovarian development, body size and colony development or survival). The foraging behaviour of treated pollinators was recorded in a semi‐field setup and, for B. terrestris, we measured the pollen amount on the body surface and the pollen deposited on stigmata after a single floral visit. Both stressors affected bumblebee health. Additionally, insecticide‐treated workers showed increased flower handling times and flight durations, while low‐quality food reduced the amount of pollen on the surface of bumblebees and the pollen deposited on stigmata. Syrphids were mostly affected by low‐quality food, which decreased their survival probability and changed their foraging behaviour. Furthermore, we found an interactive effect between the two stressors, reducing E. balteatus ovary development. Synthesis and applications. Insecticide and food stress affected fitness traits of both bumblebees and syrphid flies, possibly reducing pollinator populations under natural conditions. Especially for bumblebees, long‐term exposure led to a reduction in the provision of pollination services, both by changing their behaviour and reducing pollen transfer. We found differences between the two pollinator groups, showing that results gained from single groups like bees should not be extrapolated to all pollinators. Interactive effects indicate potential buffering effects of high‐quality food against other stressors and highlight the importance of considering synergies between multiple stressors in risk assessments. This further emphasizes the relevance of floral resources such as wild flower strips in agricultural areas to conserve pollinators and pollination services. [ABSTRACT FROM AUTHOR]

Plant‐pollinator interactions exist along a continuum from complete specialisation to highly generalised, that may vary in time and space. A long‐held assumption is that large bees are usually the most effective pollinators of generalist plants. We tested this by studying the relative importance of different groups of pollinators of Knautia arvensis (L.) Coult. (Caprifoliaceae: Dipsacoideae). This plant is suitable for such a study because it attracts a diversity of flower visitors, belonging to different functional groups. We asked whether all functional groups of pollinators are equally effective, or if one group is most effective, which has been documented in other species with apparently generalised pollination systems. We studied two subpopulations of K. arvensis, one at low and one at high density in Northampton, UK. To assess pollinator importance we exposed unvisited inflorescences to single visits by different groups of pollinators (butterflies, bumblebees, hoverflies and others) and assessed the proportion of pollinated stigmas. We then multiplied the effectiveness of each pollinator group with their proportional visitation frequency in five different years. For each group we also compared time spent on flowers and flight distance between visits. The relative importance of each pollinator group varied between years, as did their flight distances between flower visits. Butterflies were the best pollinators on a per visit basis (in terms of the proportion of stigmas pollinated) and flew further after visiting an inflorescence. Different measures and proxies of pollinator effectiveness varied between taxa, subpopulations, and years, and no one group of pollinators was consistently more effective than the others. Our results demonstrate the adaptive value of generalised pollination strategies when variation in relative abundance of different types of pollinators is considered. Such strategies may have buffered the ability of plants to reproduce during past periods of environmental change and may do so in the future. [ABSTRACT FROM AUTHOR]

Flower colour polymorphisms are uncommon but widespread among angiosperms and can be maintained by a variety of balancing selection mechanisms. Anemone palmata is mostly yellow‐flowered, but white‐flowered plants coexist in some populations. We analysed the distribution of colour morphs of A. palmata across its range. We also characterised their colours and compared their vegetative and sexual reproductive traits, pollinator attention and fitness. The range of A. palmata is limited to the Western Mediterranean, while white‐flowered plants are restricted to Portugal and SW Spain, where they occur at low proportions. Yellow flowers have a characteristic UV pattern, with a UV‐absorbing centre and UV‐reflecting periphery, which is absent in the white morph. Colour features of both morphs were highly delineated, making it easy for pollinators to distinguish them. Both morphs were protogynous, with the same duration of sexual stages, and the main floral traits related to pollinator attraction, apart from flower colour, were similar. Hymenoptera and Diptera were the main pollinators, showing preference for the yellow morph, clear partitioning of pollinator groups between the two colour morphs and a marked constancy to flower colour during foraging. Both morphs combined clonal propagation with sexual reproduction, but sexual reproductive potential was lower in white‐flowered plants. Finally, female fitness was higher in the yellow morph. Pollinator partitioning and colour constancy could maintain this polymorphism, despite the lower visitation rate and fitness of white‐flowered plants, which could facilitate their clonal propagation. [ABSTRACT FROM AUTHOR]

Despite Batesian mimicry often eliciting predator avoidance, many Batesian mimics, such as some species of hoverfly (Syrphidae), are considered to have an "imperfect" resemblance to their model. One possible explanation for the persistence of apparently imperfect mimicry is that human perceptions of mimicry are different from those of natural predators. Natural predators of hoverflies have different visual and cognitive systems from humans, and they may encounter mimics in a different way. For example, whilst humans often encounter hoverflies at rest on vegetation, or in photographs or textbooks, where they are typically viewed from above, natural predators may approach hoverflies from the side or below. To test how viewing angle affects the perception of mimicry, images of mimetic hoverflies and their models (wasps and bees) were shown from different angles in an online survey. Participants were asked to distinguish between the images of models and mimics. The results show that the viewing angle does affect perceived mimicry in some species, although it does not provide a complete explanation for the persistence of imperfect mimicry in nature. The effect is also highly species-specific. This suggests that to understand better how selection has shaped mimetic accuracy in hoverflies and other taxa, further study is required of the viewing angles that predators utilize most commonly in nature. [ABSTRACT FROM AUTHOR]

The knowledge on the distribution of saproxylic hoverflies in the Piedmont region has always been incomplete, despite the large wooded areas present in the territory. We know of a few scattered specimens collected in the 19th century, often with a generic or incomplete locality on the label such as “surrounding Turin” or “Alps”. The recent publication of the first European Red List on hoverflies highlights some threatened species including some saproxylics. To fill this knowledge gap we report here unpublished data and establish new ecological note on threatened or nationally scarce saproxylic species actually present in the region.In this study, we present new findings concerning rare saproxylic hoverflies. These include the rediscovery of Hammerschmidtia ferruginea (Fallen), 1817, marking its first recorded occurrence in the Italian fauna since the middle of 19th century. Additionally, we report novel observations of the "Chimera fly" Doros destillatorius Mik, 1885, along with further observations on endangered or vulnerable species such as Callicera spp. and Brachypalpus chrysites Egger 1859. Moreover, we document the rediscovery of Criorhina pachymera Egger, 1858, within the Piedmont region, and the first record of Brachyopa grunewaldensis Kassebeer, 2000, within Italy. Comprehensive data detailing these observations are provided herein.

Species of the subfamily Diplazontinae (Hym.: Ichneumonidae) were studied in West Azarbaijan province (Northwest of Iran). The specimens were collected using Malaise traps, during 2019–2020. Five species belonging to three genera were collected and identified. One species, Homotropus riedeli Johansson, 2020 was a new record for Iran as well as Asia. The distribution range of this species extends from Sweden to the north-west of Iran. A checklist is being compiled for 27 known Iranian species of this subfamily. In addition, a distribution map based on the recorded areas for each species within the Iranian provinces has been provided. We proposed a new direction for future biodiversity inventories of this subfamily in Iran.

Diversity, community structure, and estimation of flower fly species richness (Diptera: Syrphidae) were measured in Darab damask rose plain, Fars province, Iran. Four Malaise traps were installed in a nearly 500-hectare site from April to October 2019 and checked periodically. The 4-step integrated approach was used to assess the sample completeness profile, to infer true diversities of entire assemblages, to standardize the sample coverage, and to infer diversity via an evenness profile. To estimate the species richness of the Syrphidae community, two models and seven non-parametric indices were used. As a result, a totally of 96 specimens representing 18 species were collected in 18-Malaise trap months (MTM) sampling efforts. One species, Paragus auritus Stuckenberg, 1954 was recorded for the first time from Iran. The aphidophagous hoverflies included 76.3% of all collected specimens. The dominant species were Sphaerophoria scripta (Linnaeus, 1758), Eupeodes corolla (Fabricius, 1794), and Eumerus ahmadii Barkalov & Gharali, 2004. The estimated sample completeness profile showed that our data covers 85% of the total species in this community. Shannon and Simpson diversity indices are measured at 10.88 and 7.04, respectively. The models and non-parametric estimators estimated the species richness of syphids varied from 19 – 24 species. The biodiversity of Syrphidae community in the world's largest rain-fed organic damask rose plain, located at high altitudes of ca. 2600 m a.s.l. of the Zagros Mountains ranges in the south of Iran, provides fundamental data for any future conservation efforts of pollinators and predators and biocontrol programs of sucking pests.

Aim: Efforts to understand how pollinating insect diversity is distributed across large geographic areas are rare despite the importance of such work for conserving regional diversity. We sought to relate the diversity of bees (Hymenoptera: Apoidea), hover flies (Diptera: Syrphidae), and butterflies (Lepidoptera) to ecoregion, landscape context, canopy openness, and forest composition across southeastern U.S. forests. Location: Nineteen experimental forests across nine states in the southeastern U.S. Methods: We established 5–7 plots on each experimental forest. In each, we sampled pollinators monthly (March–September) using coloured pan traps, and collected data on local forest characteristics. We used the National Land Cover Database (NLCD) to quantify surrounding landcover at different spatial scales. Results: Bee richness was negatively correlated with both the amount of conifer (pine) forest and the extent of wetlands in the surrounding landscape but was positively correlated with canopy openness. Hover flies and butterflies were less sensitive to landscape context and stand conditions. Pollinator communities differed considerably among ecoregions, with those of the Central Appalachian and Coastal Plain ecoregions being particularly distinct. Bee richness and abundance peaked 2 months earlier in Central Appalachia than in the Coastal Plain and Southeastern Mixed Forest ecoregions. Main Conclusions: Our findings reveal ecoregional differences in pollinator communities across the southeastern U.S. and highlight the importance of landscape context and local forest conditions to this diverse fauna. The closed broadleaf forests of Appalachia and the open conifer‐dominated forests of the Coastal Plain support particularly distinct pollinator communities with contrasting seasonality. Our results suggest pine forests may reduce pollinator diversity in regions historically dominated by broadleaf forests. However, efforts to create more open canopies can help improve conditions for pollinators in planted pine forests. Research exploring associations between forest pollinators and different broadleaf tree taxa is needed to better anticipate the impacts of various management activities. [ABSTRACT FROM AUTHOR]

Episyrphus balteatus can provide dual ecosystem services including pest control and pollination, which the larvae are excellent predators of aphid pest whereas adults are efficient pollinator. In this study, we assembled a high-quality genome of E. balteatus from northern China geographical population at the chromosome level by using Illumina, PacBio long reads, and Hi-C technologies. The 467.42 Mb genome was obtained from 723 contigs, with a contig N50 of 9.16 Mb and Scaffold N50 of 118.85 Mb, and 90.25% (431.75 Mb) of the assembly was anchored to 4 pseudo-autosomes and one pseudo-heterosome. In total, 14,848 protein-coding genes were annotated, and 95.14% of genes were fully represented in NR, GO, KEGG databases. Besides, we also obtained the mitochondrial genome of E. balteatus of 16, 837 bp in length with 37 typical mitochondrial genes. Overall, this high-quality genome is valuable for evolutionary and genetic studies of E. balteatus and other Syrphidae hoverfly species. [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]

Among the many forest-dwelling invertebrates, saproxylic species play a key role in decomposition and nutrient cycling. Several saproxylic insects are threatened with extinction and depend on strict microhabitat features. Hoverflies play a key role in pollination and can be used as bioindicators of habitat conditions. Mallota fuciformis is a rarely observed saproxylic hoverfly internationally recognised as a species of conservation interest. We sampled Mallota fuciformis in oak-hornbeam stands and alluvial woodland with a standardised observation protocol of adults on flowering Prunus trees. This new sampling method proved to be efficient and non-invasive, eliminating the need to collect specimens of this rare species. Overall, 48 out of 86 sites investigated were found to be positive for the presence of the species, significantly increasing knowledge about its distribution in the region. We tested several environmental predictors to explain M. fuciformis detection, but only three were significant for the model: the presence of overmature Quercus trees, the presence of alluvial plants and the current size of the forest. Other predictors considered as proxies of landscape and past condition of the woodland showed no effect. These data confirmed the importance of the quality of forest woods (mainly the presence of large oak trees that ensure larvae development) to allow the presence of this saproxylic species. Implications for insect conservation: In the present study, we investigate the distribution and habitat requirements of M. fuciformis in order to find forest features that could be beneficial also for other, more threatened saproxylic species. This research underlines the importance of veteran trees and their microhabitats in the conservation of saproxylic species of hoverflies. We also provide an effective ad hoc protocol to monitor the target hoverfly species, which can be implemented in the assessment of rare species. [ABSTRACT FROM AUTHOR]

Over the years, thrips have transitioned from a minor nuisance to a major problem, significantly impacting the yield and quality of cotton. Unmanned aerial vehicles (UAVs) for plant protection have emerged as an effective alternative to traditional pesticide spraying equipment. UAVs offer advantages such as avoiding crop damage and enhancing pesticide deposition on the plants and have become the primary choice for pesticide application in cotton fields. In this study, a 2-year field experiment found that the thrips population in a cotton field in Xinjiang, China, exhibited gradual growth during the early flowering phase, peaking in late July. The thrips population gradually shifted from the lower canopy to the upper canopy as the cotton flowers opened layer by layer. From 09:00 to 11:00 (GMT+8) and 19:00 to 21:00 (GMT+8), thrips mainly flew outside the flowers, while from 17:00 to 19:00 (GMT+8), they mostly inhabited the inner whorls of flowers. The insecticides 10% cyantraniliprole oil dispersion and 10% spinetoram suspension concentrate, sprayed by UAV, had the best control effect on thrips, with 80.51% and 79.22% control effect after 7 days of spraying, respectively. The optimal spraying time for 10% cyantraniliprole oil dispersion was 19:00 (GMT+8), and the control effect on thrips reached 91.16% at 7 days of spraying. During the cotton flowering period, thrips inhabited flowers in the evening and flew outside during the day. The best control effect on thrips was achieved with UAV-sprayed 10% cyantraniliprole oil dispersion at 19:00 (GMT+8). [ABSTRACT FROM AUTHOR]

The extent to which weeds in arable land are useful to pollinators depends in part on the temporal pattern of flowering and insect flight activity. We compiled citizen science data on 54 bees and hoverflies typical of agricultural areas in southern Sweden, as well as 24 flowering weed species classified as pollinator‐friendly in the sense that they provide nectar and/or pollen to pollinators. The flight periods of the bees and hoverflies varied greatly, but there were also some consistent differences between the four groups studied. The first group to fly were the early flying solitary bees (7 species), followed by the social bees (18 species). In contrast, other solitary bees (11 species) and hoverflies (22 species) flew later in the summer. Solitary bees had the shortest flight periods, while social bees and hoverflies had longer flight periods. Flowering of weed species also varied greatly between species, with weeds classified as winter annuals (e.g., germinating in autumn) starting early together with germination generalists (species that can germinate in both autumn and spring). Summer annuals (spring germinators) and perennials started flowering about a month later. Germination generalists had a much longer flowering period than the others. Weekly pollinator records were in most cases significantly explained by weed records. Apart from early flying solitary bees, all models showed strong positive relationships. The overall best explanatory variable was the total number of weeds, with a weight assigned to each species based on its potential as a nectar/pollen source. This suggests that agricultural weeds in Sweden provide a continuous potential supply of nectar and pollen throughout the flight season of most pollinators. [ABSTRACT FROM AUTHOR]

Diversity, community structure, and estimation of flower fly species richness (Diptera: Syrphidae) were measured in Darab damask rose plain, Fars province, Iran. Four Malaise traps were installed in a nearly 500-hectare site from April to October 2019 and checked periodically. The 4-step integrated approach was used to assess the sample completeness profile, to infer true diversities of entire assemblages, to standardize the sample coverage, and to infer diversity via an evenness profile. To estimate the species richness of the Syrphidae community, two models and seven non-parametric indices were used. As a result, a totally of 96 specimens representing 18 species were collected in 18-Malaise trap months (MTM) sampling efforts. One species, Paragus auritus Stuckenberg, 1954 was recorded for the first time from Iran. The aphidophagous hoverflies included 76.3% of all collected specimens. The dominant species were Sphaerophoria scripta (Linnaeus, 1758), Eupeodes corolla (Fabricius, 1794), and Eumerus ahmadii Barkalov & Gharali, 2004. The estimated sample completeness profile showed that our data covers 85% of the total species in this community. Shannon and Simpson diversity indices are measured at 10.88 and 7.04, respectively. The models and non-parametric estimators estimated the species richness of syphids varied from 19 -- 24 species. The biodiversity of Syrphidae community in the world's largest rain-fed organic damask rose plain, located at high altitudes of ca. 2600 m a.s.l. of the Zagros Mountains ranges in the south of Iran, provides fundamental data for any future conservation efforts of pollinators and predators and biocontrol programs of sucking pests. [ABSTRACT FROM AUTHOR]

An updated checklist of the hoverflies including distribution and seasonal occurence data of known species in Nepal is presented. The list is based on all available published literature on taxonomy, biodiversity, ecology, and biological aspects of the syrphid fauna of Nepal up to 2023. A total of 205 species from three subfamilies and 63 genera are known to occur in Nepal. Among the three subfamilies, Eristalinae shares maximum species (111 species, 54%), followed by Syrphinae (90 species, 44%), and Microdontinae (four species, 2%). is presented. Among these, 48 (23%) species are recorded in Nepal only. The distribution of known hoverfly species in the country is not uniform, with the Bagmati (82 species) and Koshi (75 species) provinces having the greatest number of species, while the Madhesh (four species) and Lumbini (one species) provinces having the lowest records. The highest number of species are recorded in May (51 species), followed by July (50 species) and June (48 species). Winter season records are relatively low, and distribution data are still incomplete for some sites. Based on the present review, comprehensive and systematic sampling across the entire country is necessary for further exploration of Nepal's hoverfly fauna. [ABSTRACT FROM AUTHOR]

Species of the subfamily Diplazontinae (Hym.: Ichneumonidae) were studied in West Azarbaijan province (Northwest of Iran). The specimens were collected using Malaise traps, during 2019-2020. Five species belonging to three genera were collected and identified. One species, Homotropus riedeli Johansson, 2020 was a new record for Iran as well as Asia. The distribution range of this species extends from Sweden to the north-west of Iran. A checklist is being compiled for 27 known Iranian species of this subfamily. In addition, a distribution map based on the recorded areas for each species within the Iranian provinces has been provided. We proposed a new direction for future biodiversity inventories of this subfamily in Iran. [ABSTRACT FROM AUTHOR]

Fruit and vegetable crops are affected by numerous arthropods, including aphids and thrips. Hoverfly adults are important pollinators, and their larvae are mainly aphid predators. Molecular studies on the stomach contents of larvae allowed to associate hoverflies with the consumption of other soft‐bodied arthropods, including thrips, with few records found in Neotropical hoverfly species. Allograpta exotica (Wiedemann) (Diptera: Syrphidae), a species widely distributed in the Americas, from the USA to Argentinian Patagonia, has been associated with numerous crops mainly affected by aphids, and to a lesser extent with whiteflies. The objective of this work was to assess the consumption and preference rates of various instars of A. exotica as biocontrol agents for two major insect pests, Myzus persicae (Sulzer) (Hemiptera: Aphididae) and Frankliniella gemina (Bagnall) (Thysanoptera: Thripidae), under controlled laboratory conditions. Additionally, we morphologically characterized the three larval stages of A. exotica. We determined that all three instars of A. exotica consume both M. persicae and F. gemina, and that they kill more thrips than aphids. Still, A. exotica preferred M. persicae over F. gemina, even when the relative aphid availability decreased compared to F. gemina, although consumption of both prey types remained high. Interestingly, A. exotica second instars consumed four times more thrips than aphids. This study explored the potential use of one of the most common hoverfly species in fruit and vegetable crops as a biocontrol agent of aphids and thrips. Further laboratory and field studies should explore more deeply the potential of this Neotropical beneficial dipteran. [ABSTRACT FROM AUTHOR]

Imidacloprid is a widely used pesticide in agriculture. It is being found in aquatic ecosystems in agricultural regions. This study aimed to evaluate its effects on the survival rates, acetylcholinesterase (AChE) and catalase (CAT) responses of larval Eristalis tenax hoverflies. The larvae were exposed for 3, 7 and 14 days to increasing concentrations of imidacloprid (0, 0.1, 0.5 and 2 mg L−1) both indoors at a constant temperature of 20 °C and outdoors under varying environmental conditions. The results revealed that indoors and outdoors, the mortality of E. tenax significantly increased with increasing imidacloprid concentration and duration of exposure. Median lethal concentrations (LC50) varied from 0.03 to 0.17 mg L−1 depending on the duration and conditions of exposure. Indoors, AChE activity decreased in all the treatments for all three exposure durations, whereas outdoors the decrease was observed after the short (3-day) and long (14-day) exposure durations. AChE inhibition ranged from 6% to 62% (indoors) and 12% to 62% (outdoors). Variations in CAT activity were observed for both experimental setups, with a decrease outdoors in larvae exposed to 0.5 mg L−1 for 7 days and a gradual dose-dependent increase indoors for exposure lasting 3 and 7 days. This study sheds light on the potential ecological implications of imidacloprid contamination which may cause the decline of aquatic insect populations and pollination rates, leading to disruptions of the food chain and the overall decline of aquatic and terrestrial ecosystem health. [ABSTRACT FROM AUTHOR]

Two hover-flies of the Genus Mesembrius Rondai, 1857; M. bengalensis (Wiedemann, 1819), and M. quadrivittatus (Wiedemann, 1819) are reported for the first time from Kerala along with their diagnosis and key. [ABSTRACT FROM AUTHOR]

Milesia crabroniformis (F.) is a large hornet-mimic hoverfly considered relatively rare in Italy. During visual samplings along a transect carried out in Castiglione dei Pepoli (Bologna, Italy), with the aim of monitoring changes in hoverfly communities over sixty years, the authors observed and counted at least one hundred specimens of this hornet-mimic hoverfly while foraging on Sambucus ebulus L. This note aims to document this very infrequent behaviour of M. crabroniformis to contribute to the understanding of this phenomenon. [ABSTRACT FROM AUTHOR]

The clean and abundant nature of photovoltaic technology makes it eminent among other renewable energy sources and to obtain the best benefit from these sources, an efficient maximum power point tracking technique is needed that can produce the required output even under varying environmental conditions. This work deals with the development of a global maximum power point tracking technique combining bio-inspired algorithms and one-cycle control which helps in effective tracking even under partial shading conditions. This technique generates signals for the KY converter from the duty cycle obtained from bio-inspired algorithms. The voltage at the output of the photovoltaic panel is fed to the load through KY converter. The analysis of the system is carried out using resistive load under different patterns of the photovoltaic array using particle swarm optimization, flower pollination and flying squirrel search optimization algorithms through simulation and experimentation. The performance indices like tracking speed, tracking efficiency and steady-state oscillations are taken for comparison with the existing systems without one-cycle control, and the results indicate its capability in GMPP tracking with an average efficiency and tracking time of 99.1% and 0.13 s, respectively. [ABSTRACT FROM AUTHOR]

While transect walks have long been the preferred monitoring method for many flying insect taxa, malaise traps combined with DNA metabarcoding have gained growing prominence. However, it remains unclear whether both methods reveal comparable species richness and the same ecological drivers along environmental gradients. We selected three groups of pollinators (wild bees, hoverflies and butterflies) and one group of herbivores (grasshoppers) as functionally important and conservation‐relevant model groups, comparing results of both methods along an elevational gradient in the German Alps. Across the study region, both methods detected a similarly high species richness of pollinators with ~50% overlap of species pools, but transect walks revealed more species per site, especially in higher elevations and under low temperatures. Body size spectra differed between methods, with on average more large butterfly and more small bee species in transect walks. Nevertheless, temperature and flower richness were consistent drivers of pollinator richness, independent of the sampling method. Grasshopper richness from transect walks was considerably higher than from malaise traps. Both methods identified temperature and only malaise traps also identified management as drivers of grasshopper richness. We conclude that malaise traps are principally suitable substitutes for the more time‐consuming pollinator transect walks. However, the effectiveness of these passive traps is more susceptible to changes in sampling temperature, and in some pollinator groups, body size classes are presented differently, which is important to consider during analyses. For grasshoppers, transect walks appear to be more suitable to assess species richness, as considerably more species can be monitored. [ABSTRACT FROM AUTHOR]

The species of the hoverfly genus Paramixogaster Brunetti, 1923 from the Oriental Region are revised. The resulting number of valid species is 15, of which the following four are described as new: P. halmaherensis Reemer, sp. nov., P. jubata Reemer, sp. nov., P. kodaiana Sankararaman & Reemer, sp. nov., and P. sulawesiana Reemer, sp. nov. Three new synonymies are established: Paramicrodon decipiens de Meijere, 1917, syn. nov. is a junior synonym of Microdon vespiformis de Meijere, 1908; Paramixogaster wegneri Keiser, 1964, syn. nov. is a junior synonym of Ceratophya indica Doleschall, 1857; Microdon subpetiolatus Thompson, 2020, syn. nov. is a junior synonym of Microdon contractus Brunetti, 1923. Paramixogaster huoi Reemer, nom. nov. is introduced as a replacement name for P. trifasciatus Huo & Zhao, 2022, which is a primary homonym of P. trifasciatus Ssymank & Reemer, 2016. Neotypes are designated for Paramixogaster icariiformis Pendlebury, 1927 and Myxogaster variegata Sack, 1922, and a lectotype is designated for Microdon vespiformis de Meijere, 1908. An identification key to the species and diagnoses for all species are provided. [ABSTRACT FROM AUTHOR]

Unlike European species, the potential of Nearctic syrphids as biological control agents is still poorly studied. However, the American hoverfly, Eupeodes americanus (Wiedemann), has recently demonstrated promising traits as a biocontrol agent, notably against the foxglove aphid, Aulacorthum solani Kaltenbach, on pepper. The present study aims to extend our knowledge of the American hoverfly by evaluating its potential as a biocontrol agent in a banker plant system against the melon aphid, Aphis gossypii Glover, in a greenhouse cucumber crop. The preimaginal development and voracity of E. americanus were compared when preying upon the focal prey/pest (A. gossypii) or the banker prey (bird cherry‐oat aphid, Rhopalosiphum padi L.) by daily observations of larvae from egg to adult. Preimaginal development time, survival rate, and occurrence of deformation were similar on both prey species. The weight of third instar and pupae, however, was higher for larvae that fed on the banker prey. The ad libitum voracity of the syrphid larvae was generally very high and did not significantly differ between prey species, except for the third‐instar larvae which consumed more focal prey. Results suggest that a banker plant system involving the bird cherry‐oat aphid may be a promising tactic for utilizing E. americanus for melon aphid biocontrol. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum) is a major cereal crop of the world and provides 20% of the world's food calories. Pakistan's average wheat production is 24.946 million tons, contributing 1.7% of the country's gross domestic product (GDP). Aphids are a significant insect pest of wheat, causing crop injury by sucking cell sap, releasing honeydew, interfering with the photosynthetic activities of the crop, and transmitting pathogenic viruses. In the present study identification of wheat, aphid species and assessment of IPM modules for aphid management have been worked out. Aphids can be identified based on body color, cornicle tube (length, shape, orientation etc.) and length of antennae. Coccinella septempunctata, Hover flies, Chrysoperla carnea and spiders play a significant role in the management of wheat aphid as a biocontrol agent. So, it is concluded that natural enemies, seed dressing, botanical extracts and sticky traps were found effective and eco-friendly as compared to synthetic insecticides. [ABSTRACT FROM AUTHOR]

Merodon triangulum Vujić, Radenković & Hurkmans, 2020 is a European endemic hoverfly species belonging to Merodon constans species-group, inside albifrons-lineage. The distribution of this species is known to be mostly central Europe and Balkan peninsula and it has been categorized as Near Threatened in the European IUCN red list of hoverflies; this paper cites the species for the first time in Ukraine (western Ukraine, specifically). In the present study, the preimaginal stages of this species are described and figured using Scanning Electron Microscopy. The material used for the descriptions were larvae collected in Ukraine and Serbia feeding inside underground storage organs of the spring snowflake Leucojum vernum L., 1753. This morphological description constitutes the first one inside the constans species-group, and the sixth description of the albifrons-lineage, in which there is only one species-group left to have at least one species of the preimaginal stages described (i.e., ruficornis species-group). The descriptions were compared with the rest available of the genus, stating the diagnostical characters of the present species and the shared characters inside the lineage. The novel information provided on the trophic interaction between M. triangulum larvae and Leucojum bulbs is stated for the first time and further supports the association of the constans species-group with the underground storage organs of snowflakes and snowdrops (Galantheae) in their role as host plants. [ABSTRACT FROM AUTHOR]

Simple Summary: Hoverflies, also known as flower flies, are a highly diverse group of two-winged flies with more than 6000 known species worldwide. This group of insects plays an important role in ecosystems, providing services such as plant pollination and pest control, among others. Regarding Eumerus, this hoverfly genus is one of the most speciose in the Palaearctic region, where new species are continually being discovered. Nevertheless, the great morphological variability of some species makes their identification and classification difficult. Therefore, the main aim of the present work was to assess the variability of the species of the Eumerus barbarus group in the western Mediterranean area under an integrative study (i.e., combining different techniques and data sources). We found high levels of morphological and genetic variability in two species of this group. Based on our findings, we described a new species from the island of Sardinia and provided the most comprehensive identification key for the males of this Eumerus species group from the western Mediterranean. Comprising nearly 300 described species, Eumerus Meigen, 1822, is one of the most speciose syrphid genera worldwide, and its taxonomic diversity is remarkable in the Mediterranean basin. The Eumerus barbarus (Coquebert, 1804) group consists of four species in the western Mediterranean. Although the phenotypic variability of this species group has been commented on in previous studies, it has never been contrasted with molecular data. In the present work, the morphological variation found in 300+ specimens of this species group from the western Mediterranean is explored and tested against the COI mitochondrial DNA (mtDNA). The highest phenotypic disparity was found in E. barbarus and Eumerus sulcitibius Rondani 1868. The integrative approach has not revealed cryptic diversity within the species E. barbarus but in E. sulcitibius. As a result, a new species close to E. sulcitibius was discovered, Eumerus sardus Aguado-Aranda, Ricarte & Hauser sp. n., from Sardinia, Italy. The new insular species is here described, illustrated, and discussed. A total of twenty-three haplotypes of COI mtDNA were identified amongst the analyzed Mediterranean specimens of E. barbarus, whereas two and five haplotypes were distinguished in the Iberian specimens of E. sulcitibius and Eumerus gibbosus van Steenis, Hauser & van Zuijen, 2017, respectively. Moreover, the first known barcodes of E. gibbosus and Eumerus schmideggeri van Steenis, Hauser & van Zuijen, 2017 were obtained, and the distribution ranges of all species are mapped. An updated dichotomous key to the males of the E. barbarus group from the western Mediterranean is provided. [ABSTRACT FROM AUTHOR]

Hoverflies (Syrphidae) are essential pollinators, and their severe decline jeopardizes their invaluable contribution to plant diversity and agricultural production. However, we know little about the dispersal abilities of hoverflies in urbanized landscapes, limiting our understanding of the spatiotemporal dynamics of plant–pollinator systems and reducing our ability to preserve biodiversity in the context of global change. Previous work has not addressed how urbanization affects the functional connectivity of hoverflies and whether dispersal is a limiting factor in their population dynamics. In this study, we investigated the spatial genetic structure of two nonmigratory species of hoverflies in two urban areas. We collected more than a thousand specimens of each Syritta pipiens and Myathropa florea, each, by hand netting in two western European urbanized study areas of 490 and 460 km2 in 2021, and we genotyped them at 14 and 24 microsatellite loci, respectively. Based on spatial and nonspatial Bayesian clustering methods, we failed to reject the null hypothesis of panmixia, suggesting that both species exhibited high genetic connectivity despite urbanization. The distribution of allele frequencies was not correlated with geographic distance, implying that isolation‐by‐distance was negligible at the investigated spatial scale in both species. Although anthropogenic land cover changes generally have dramatic consequences on biodiversity, these hoverfly species retain high connectivity, which suggests that dispersal is not a strong limiting factor in their metapopulational dynamics. However, high effective population size and its confounding effect on signals of genetic drift may limit our ability to conclude confidently about landscape effects on gene flow in those two species. Provided we maintain or restore habitat, recolonization may be prompt even in urban areas. [ABSTRACT FROM AUTHOR]

Syrphine hoverflies (Diptera: Syrphinae) are important predators of aphids in agricultural crops. While the use of flowering plants to enhance their efficacy is well established, recent research has developed an artificial diet for adult hoverflies consisting of a sugar solution and pollen in a dispenser. To ensure that the artificial diet is suitable to support hoverfly reproduction, a comparative analysis was conducted between a natural diet of flowering buckwheat plants versus an artificial diet consisting of artificial flowers (including honey solution and pollen), complemented by a sugar solution disperser. The study evaluated the fecundity, fertility, oviposition period, egg hatchability, and overall lifespan of the American hoverfly, Eupeodes americanus (Wiedemann 1830). The results indicate that the artificial diet does not negatively impact the reproductive parameters of E. americanus when compared to the buckwheat-based diet. Consequently, artificial diets emerge as a promising and more convenient alternative to flowering plants to support hoverflies in biological control strategies and for their mass rearing in research facilities and commercial insectaries. [ABSTRACT FROM AUTHOR]

This study focuses on the avidus–nigritarsis lineage within the genus Merodon, exploring morphological, genetic, and distributional aspects of two related assemblies within this lineage: the clavipes and pruni species groups. An integrative taxonomic approach was followed to ensure comprehensive species identification and validation, using adult morphology, wing geometric morphometrics, and genetic analysis of the mtDNA COI gene. In the clavipes group, seven species were identified, including three new species: M. aenigmaticus Vujić, Radenković & Likov, sp. nov., M. latens Vujić, Radenković & Likov, sp. nov., and M. rufofemoris Vujić, Radenković & Likov, sp. nov. In the pruni group, our revision revealed a new species, M. aequalis Vujić, Radenković & Likov, sp. nov., and the revalidation of Merodon obscurus Gil Collado, 1929, stat. rev. Merodon pallidus Macquart, 1842 is redescribed. Diagnoses, identification keys to species, and distribution maps are provided, and neotypes for Syrphus clavipes Fabricius, 1781 and Merodon quadrinotatus (Sack, 1931) are designated. Additionally, the following new synonyms are proposed: M. clavipes albus syn. nov., M. clavipes ater syn. nov., M. clavipes niger syn. nov., and M. splendens syn. nov. are junior synonyms of M. clavipes; and M. velox armeniacus syn. nov. and M. velox anathema syn. nov. are junior synonyms of M. velox. [ABSTRACT FROM AUTHOR]

Land‐use management is a key factor causing pollinator declines in agricultural grasslands. This decline can not only be directly driven by land‐use (e.g., habitat loss) but also be indirectly mediated through a reduction in floral resource abundance and diversity, which might in turn affect pollinator health and foraging. We conducted surveys of the abundance of flowering plant species and behavioural observations of two common generalist pollinator species, namely the bumblebee Bombus lapidarius and the syrphid fly Episyrphus balteatus, in managed grasslands of variable land‐use intensity (LUI) to investigate whether land‐use affects (1) resource availability of the pollinators, (2) their host plant selection and (3) pollinator foraging behaviour. We have found that the floral composition of plant species that were used as resource by the investigated pollinator species depends on land‐use intensity and practices such as mowing or grazing. We have also found that bumblebees, but not syrphid flies, visit different plants depending on LUI or management type. Furthermore, LUI indirectly changed pollinator behaviour via a reduction in plot‐level flower diversity and abundance. For example, bumblebees show longer flight durations with decreasing flower cover indicating higher energy expenditure when foraging on land‐use intensive plots. Syrphid flies were generally less affected by local land use, showing how different pollinator groups can differently react to land‐use change. Overall, we show that land‐use can change resource composition, abundance and diversity for pollinators, which can in turn affect pollinator foraging behaviour and potentially contribute to pollinator decline in agricultural grasslands. [ABSTRACT FROM AUTHOR]

Wheat aphids are major pests of wheat and a significant threat to global food security. Eupeodes corollae Fabricius is one of the dominant species of wheat field hoverflies, but its ability and role in wheat aphid control lack systematic research. This study on the predatory function responses of E. corollae to Rhopalosiphum padi Linnaeus, Schizaphis graminum Rondani, and Sitobion miscanthi, Takahashi showed that the maximum daily predation (1/Th) of 2nd instar E. corollae larvae was 166.67, 125.00, and 142.86, and that of 3rd instar larvae was 333.33, 250.00, and 250.00, respectively. The cage simulation test indicated that the wheat aphid population decline rate was 100% at the 60th hour of inoculation of 3rd instar E. corollae larvae at a 1:100 ratio. Eupeodes corollae exhibited a predatory relationship with all three wheat aphid species in the wheat fields of Hebei Province, China, and the corrected predation detection rates of E. corollae larvae against R. padi, S. graminum, and S. miscanthi were 12.36%, 1.08%, and 28.77% in 2022, and 6.74%, 0.82%, and 37.56% in 2023, respectively. The results of this study clarify the predatory ability of E. corollae on wheat aphids and the predatory relationship between them and provide technical support for the management of wheat aphids using the bio-control ecological service function of E. corollae. [ABSTRACT FROM AUTHOR]

Simple Summary: The scarce genus of Pelecocera Meigen, 1822 (Diptera: Syrphidae) from the Holarctic Region has 14 species described. The taxonomic diagnosis of the immature stages of Pelecocera has not been performed; however, Pelecocera (Chamaesyrphus) japonica (Shiraki, 1956) larvae were found feeding on Rhizopogon roseolus in Japan. Following the findings in Japan, larvae of Pelecocera were collected in Denmark. We here report the first morphological description of the immature stages of Pelecocera (Chamaesyrphus) lugubris and Pelecocera (Pelecocera) tricincta, as well as specific data on their breeding sites. Larvae of both species were collected feeding on Rhizopogon luteolus in Denmark. The morphology of immature stages of P. lugubris and P. tricincta was studied by using both a scanning electron microscope and a stereomicroscope. A taxonomic diagnosis of the immature stages of Pelecocera and a taxonomic key are provided to separate them from the larvae of other genera. With 14 species, Pelecocera Meigen, 1822 is a scarce and small genus of hoverflies (Diptera: Syrphidae: Rhingiini) from the Holarctic Region. Apart from the finding of larvae of Pelecocera (Chamaesyrphus) japonica (Shiraki, 1956) in fungi in Japan, the larval biology of these hoverflies is virtually unknown. The early stages of all Pelecocera species are undescribed. The adults of Pelecocera (Pelecocera) tricincta Meigen, 1822 and Pelecocera (Chamaesyrphus) lugubris Perris, 1839 are found in Palearctic conifer forests with sand dunes. We here report the first morphological evidence of the immature stages of Pelecocera (P. lugubris and P. tricincta), as well as specific data on their breeding sites. Larvae of both species were collected feeding on the hypogean basidiomycete Rhizopogon luteolus Fr. & Nordholm, 1817 in Denmark in 2021. The first larval stage and second larval stage of P. tricincta, the third larval stage of P. lugubris, the anterior respiratory process, and the posterior respiratory process of the puparia of these two species were analyzed and studied using stereomicroscope and scanning electron microscope techniques. The chaetotaxy of the puparium of each species is also described and illustrated. A taxonomic diagnosis of the larvae of the genus Pelecocera is proposed to separate them from the larvae of other genera of the tribe. [ABSTRACT FROM AUTHOR]

Syrphid larvae are effective biological control agents in numerous crops due to their voracity, and they are used in both augmentative and conservation‐based strategies within horticultural systems. This study conducted laboratory trials to ascertain the predation rate of Allograpta exotica (Wiedemann) (Diptera: Syrphidae) on Chaetosiphon fragaefolii (Cockerell) (Hemiptera: Aphididae) and to compare it with the predation rate on Aphis gossypii Glover (Hemiptera: Aphididae), another significant aphid species affecting strawberries. Additionally, field trials were conducted to assess the reduction in the field population of C. fragaefolii achieved by A. exotica within strawberry crops. We observed a significant increase in the number of aphids consumed by a larva as it progressed from first‐instar larvae (L1) to third‐instar larvae (L3). Specifically, the mean aphid consumption by second‐instar larvae (L2) was nearly 11 times higher for C. fragaefolii and 10 times higher for A. gossypii compared to L1. Furthermore, the consumption rate of L3 larvae was approximately 2 times higher for both aphid species compared to L2. In laboratory conditions, A. exotica larvae significantly reduced the number of both aphid species, but the control on A. gossypii was higher than on C. fragaefolii. The results of the field experiment demonstrated that the predatory hoverfly A. exotica significantly reduced the numbers of C. fragaefolii compared to the control treatment, highlighting its potential as a promising biological control agent in strawberry crops. [ABSTRACT FROM AUTHOR]

A checklist of the hover flies from Kerala belonging to two subfamilies is provided. Among the 59 species listed, the subfamily Syrphinae shares maximum number of species (34), followed by the subfamily Eristalinae (25). [ABSTRACT FROM AUTHOR]

Several populations of a species of death camas (Anticlea elegans) (Melanthiaceae) were found growing and flowering above treeline in the remote Lemhi Mountains of southeastern Idaho USA. The predominant floral visitors were flies representing four families, particularly the Syrphidae. Many individual flies bore visible loads of Anticlea pollen. Various native bees were seen foraging in the locale, but all visited flowers other than Anticlea. The flies, as well as ants, fed from the tepal nectaries. Despite the plant’s common name, no foragers appeared to be impaired by imbibing its nectar. High in a neighbouring mountain range, A. elegans was being used as a trysting site by numerous Tenthredo sawflies. This is the first report of floral visitors to any Anticlea and among the first for any wildflower population above treeline in the vast US Intermountain West.

In Poland, the share of Diptera in the species composition of the harmful entomofauna occurring on vegetable crops ranges from 20 to 25%. They occur on all vegetables grown in Poland (over 80 species and botanical varieties). Since the systematic registration of pests inhabiting crops in Poland in 1919, over 70 species of flies have been listed as pests of vegetable plants. Species from three families dominate in terms of population and numbers: Anthomyiidae with 12 species (Delia radicum, on early and late cultivars of cruciferous vegetables, mainly broccoli, cauliflower, white cabbage, kohlrabi, and radishes; Delia platura occurs annually on bean and cucumber; Delia antiqua on onion and garlic; and Pegomya hyoscyami on beetroot), Cecidomyiidae with 10 species (two species dominate, Contarinia nasturtii and Dasineura napi, on cruciferous vegetables), and Agromyzidae with 23 species (Liriomyza bryoniae on cucumbers, tomatoes, and peppers, and Phytomyza gymnostoma on leeks). Short-term, gradational occurrence of some dominant species was found, including Botanophila gnava (lettuce), Chamaepsila rosae (carrot, parsley), Delia platura (asparagus, bean), Delia radicum (broccoli, cauliflower, kohlrabi, radishes, white cabbage), Phytomyza gymnostoma (leek), Oscinella frit (corn), and Suillia lurida (garlic). However, they did not affect the level of plant production in the following years of cultivation. Apart from phytophagous species, taxa with a different trophic structure are common. These are copro-, necro-, sapro-, and zoophagous species. The most numerous were flies from the Drosophilidae family (Drosophila busckii, Drosophila limbata, Scaptomyza pallida, Fanniidae (Fannia canicularis, Fannia scalaris), Heleomyzidae (Tephrochlamys tarsalis), and Muscidae (Muscina levida, Muscina stabulans, Phaonia trimaculata). Natural enemies of insects play an important role in vegetable agrocenoses. Species belonging to the order of Coleoptera beetles (Carabidae and Staphylinidae), Syrphidae, Tachinidae, and Muscidae, mainly Phaonia trimaculata larvae, play the most important role in reducing the number of Diptera. In addition, the number of phytophages is limited by other organisms, e.g., Diplopoda, Nematoda, Arachnida, and pathogens of viral, bacterial, and fungal origin.

Simple Summary: In this paper, the Merodon avidus (Diptera, Syrphidae) species complex was revised, whereupon we discovered and described four new species for science. An integrative taxonomy approach was used to delimit species boundaries. The molecular analysis, the differences in the shape of the wings, the morphological characters of the adults and the distribution ranges successfully separated all species from the complex. In this paper, the Merodon avidus (Diptera, Syrphidae) species complex was revised, whereupon we discovered and described four new species for science: Merodon atroavidus Vujić, Radenković et Likov sp. nov., M. magnus Vujić, Kočiš Tubić et Ačanski sp. nov., M. nigroscutum Vujić, Radenković et Likov sp. nov. and M. pseudomoenium Vujić, Kočiš Tubić et Ačanski sp. nov. An integrative taxonomy approach was used to delimit species boundaries. Two molecular markers (the mitochondrial COI gene and nuclear 28S rRNA gene—newly analysed marker for the complex) and geometric morphometry of the wing shape, together with morphological data and distribution, successfully separated all species from the complex. The morphological variability of the analysed species is described and discussed and an illustrated diagnostic key for typical morpho-forms of species from the M. avidus complex is presented. A distribution map of all investigated species from the complex is provided. The level of endemicity of the M. avidus complex was discussed. [ABSTRACT FROM AUTHOR]

Bumblebees have become model organisms for cognitive ecology and social learning. Quantifying the foraging behavior of free-flying bees, however, remains a methodological challenge. We describe and provide the code for a method of studying bee free flying foraging behavior using the open source neural-network based markerless tracking software DeepLabCut. From videos of bees foraging in an arena we trained a neural network to accurately track the position of each bee. We then used this approach to study foraging behavior and show that the ratio between flying time and flower visiting time decreases over repeated foraging bouts, indicating increasing efficiency of bee foraging behavior with experience. Visit durations, a laborious metric to measure by hand, were significantly shorter on flowers that had previously been visited. This experiment illustrates the usefulness of DeepLabCut for objective quantification of behavior, and in this case study shows that previous experience increases bee foraging efficiency. [ABSTRACT FROM AUTHOR]

Mosquitoes exhibit distinctive flight characteristics, utilizing a combination of very small stroke amplitudes and high stroke frequencies. This study focuses on assessing the power requirements for hovering mosquitoes through numerical simulation of wing flow and aerodynamic power, coupled with analytical computation of wing inertial power. Our findings reveal that, despite the elevated stroke frequency, the primary contributor to power expenditure is the aerodynamic power, with wing inertial power being relatively negligible due to the diminutive wing mass. The specific power necessary for hovering is approximately 35 W/kg, comparable to the requirements of various other insects such as bees, flies, and moths (ranging from 20 to –60 W/kg). Moreover, the incorporation of a 100% elastic storage system yields only marginal power savings, approximately 3.5%. Consequently, while an elastic system proves somewhat beneficial, it is not indispensable for mosquito flight. Notably, altering stroke amplitude and frequency for hovering could potentially reduce power demands compared to real-case scenarios, suggesting that the conventional small stroke amplitude and high stroke frequency utilized in mosquito flight may not be the optimal choice in terms of power efficiency. The adoption of these flight characteristics in mosquitoes may be attributed to other factors, such as providing flexibility to increase amplitude in cases of substantial weight gain due to blood-feeding or conferring a selective advantage in acoustic communication through high stroke frequency. [ABSTRACT FROM AUTHOR]

Tool use by animals, traditionally studied mainly in captive primates due to its relevance to human evolution, has been investigated in both free-ranging and captive mammals. Here, I present a report on tree bark and branch use behaviours by a free-ranging Japanese marten (Martes melampus). The marten put its face in a water-filled container, looking for something, and then it proceeded to make a scooping motion with a bark held in its mouth. Subsequently, it picked up a branch with its mouth and tried to scoop something from the water with it. Upon inspecting the container approximately 2 weeks later, I found a larva belonging to the family Syrphidae. While it is unclear if the marten was trying to catch this larva, its behaviour resembled reach extension behaviour seen in chimpanzees. The use of bark or branches may provide an advantage by allowing access to objects in hard-to-reach positions. [ABSTRACT FROM AUTHOR]