Hoverfly Species Research Articles

Aphidophagous hoverflies reduce foxglove aphid infestations and improve seed set and fruit yield in sweet pepper

Larvae of many hoverfly species prey upon aphids, whereas the adults, by relying on nectar and pollen, contribute to the pollination of many plant species. Despite their great potential for pest control and pollination, important gaps still exist regarding the efficacy of hoverflies in regulating infestations of major aphid pests in augmentative biological control programs. Here, we tested the potential of the commercially available hoverflies Eupeodes corollae and Sphaerophoria rueppellii to regulate populations of the foxglove aphid Aulacorthum solani in sweet pepper. In a semi-field experiment, aphid numbers were 93.2% and 78.4% lower in the E. corollae and S. rueppellii treatments, respectively, compared to the control. Fruit yield was increased by 390% and 361% and seed set by 395% and 399% for E. corollae and S. rueppellii. In a separate laboratory trial, we found that under conditions of limited prey, hoverfly larvae did not complete development, but that larvae of S. rueppellii survived significantly longer than larvae of E. corollae. We have shown for the first time that E. corollae and S. rueppellii can reduce infestations of foxglove aphid in sweet pepper. The limited amount of prey, related to the small size of the A. solani colonies, means that hoverfly larvae were often not able to complete development. In practice, repeated releases of hoverflies, possibly in combination with other natural enemies, might be used to achieve effective suppression of A. solani infestations. © 2021 Society of Chemical Industry.

Distribution of wild bee (Hymenoptera: Anthophila) and hoverfly (Diptera: Syrphidae) communities within farms undergoing ecological transition

BackgroundIn Havelange (Belgium), two farms are experiencing an ecological transition. We aimed to evaluate the impact of their agricultural activities on insect pollinator communities. This article depicts the situation at the very early stage of the farm transition. This study supports the fact that the maintenance of farm-level natural habitats provides environmental benefits, such as the conservation of two important pollinator communities: wild bees and hoverflies.New informationOver two years (2018-2019), by using nets and coloured pan-traps, we collected 6301 bee and hoverfly specimens amongst contrasting habitats within two farmsteads undergoing ecological transition in Havelange (Belgium). We reported 101 bee species and morphospecies from 15 genera within six families and 31 hoverfly species and morphospecies from 18 genera. This list reinforces the national pollinator database by providing new distribution data for extinction-threatened species, such as Andrena schencki Morawitz 1866, Bombus campestris (Panzer 1801), Eucera longicornis (L.) and Halictus maculatus Smith 1848 or for data deficient species, such as A. semilaevis Pérez 1903, A. fulvata (Müller 1766), A. trimmerana (Kirby 1802) and Hylaeus brevicornis Nylander 1852.

Insect biomass decline scaled to species diversity: General patterns derived from a hoverfly community

Reports of declines in biomass of flying insects have alarmed the world in recent years. However, how biomass declines reflect biodiversity loss is still an open question. Here, we analyze the abundance (19,604 individuals) of 162 hoverfly species (Diptera: Syrphidae), at six locations in German nature reserves in 1989 and 2014, and generalize the results with a model varying decline rates of common vs. rare species. We show isometric decline rates between total insect biomass and total hoverfly abundance and a scale-dependent decline in hoverfly species richness, ranging between -23% over the season to -82% at the daily level. We constructed a theoretical null model to explore how strong declines in total abundance translate to changing rank-abundance curves, species persistence, and diversity measures. Observed persistence rates were disproportionately lower than expected for species of intermediate abundance, while the rarest species showed decline and appearance rates consistent with random expectation. Our results suggest that large insect biomass declines are predictive of insect diversity declines. Under current threats, even the more common species are in peril, calling for a reevaluation of hazards and conservation strategies that traditionally target already rare and endangered species only.

Six new hoverfly species (Diptera: Syrphidae) in the fauna of Serbia

During a survey conducted from 2018 to 2021, six hoverfly species were registered on the territory of Serbia for the first time: Chalcosyrphus pannonicus (Oldenberg, 1916), Chrysogaster coemiteriorum (Linnaeus, 1758), Eristalinus taeniops (Wiedemann, 1818), Melanogaster parumplicata (Loew, 1840), Merodon testaceus Sack, 1913 and Psilota atra (Fallén, 1817). Data about new records are presented.

Spatio-temporal variation of predatory hoverflies (Diptera: Syrphidae) and their relationship with aphids in organic horticultural crops in La Plata, Buenos Aires

Population variations of predatory hoverflies in agroecosystems depend mainly on the resources that crops and wild vegetation provides them as well as death caused by natural enemies. We identified I) aphidophagous hoverfly species in lettuce and broccoli crops in Buenos Aires, II) the seasonal variations of the immature stages and their larval parasitism, and III) the wild plants, surrounding the crops, visited by adults. Fortnightly, 30 leaves were randomly selected in both crops during 2018-2019 and immature stages of syrphids and aphids per leaf were recorded. Adults were manually collected in patches of the wild plants (during 10 min of direct observations), and plants visited by adults were determined. The hoverflies were Allograpta exotica Wiedemann and Toxomerus duplicatus Wiedemann. Only A. exotica was recorded in crops. The dominant aphids were Myzus persicae (Sulzer) in lettuce and Brevycorine brassicae (L.) in broccoli. Parasitism rates ranged between 8 and 100% and the species were Diplazon laetatorius (Fabricius), in both crops, and Pachyneuron aff. nelsoni only in broccoli. Galinsoga parviflora Cav. and Matricaria chamomilla L. were the wild plants most often visited by hoverflies. This work provides basic information for the control of aphids by hoverflies in the framework of conservation biological control

Comparison of defence buzzes in hoverflies and buzz‐pollinating bees

AbstractBees and many flies, particularly hoverflies (Syrphidae), have evolved a diverse range of mechanisms to gather pollen from a wide variety of flowering plants. Bees and hoverflies use protein‐rich pollen as a food resource to mature reproductive organs and eggs and, in bees, to feed their larvae. A particularly striking pollen‐collecting behaviour involves the production of thoracic vibrations to dislodge pollen from flowers. Vibratile pollen collection is widespread in bees (>11 600 species) but extremely rare in flies (~1 species of hoverfly). Why the use of floral vibrations to collect pollen is so rare among flies is currently unknown. A hypothesis proposed to explain why flies do not engage in vibratile or buzz pollination is that they are unable to reach the vibration amplitude required to expel pollen from anthers. Here we document, for the first time, the mechanical properties of non‐flight thoracic vibrations produced by hoverflies and compare them to the vibrations produced by buzz‐pollinating bees under similar contexts (defence buzzes). We analysed ~4000 vibrations produced by nearly 300 individuals representing 20 species of hoverflies and 22 bee taxa, recorded using a miniature piezoelectric accelerometer. We characterised both frequency and acceleration amplitude components of non‐flight thoracic vibrations and their relationship to insect size. Our results show that, after accounting for size, buzz‐pollinating bees and hoverflies produce vibrations with similar acceleration. We show experimentally that the acceleration amplitude produced by some hoverflies is sufficient to elicit pollen release from buzz‐pollinated flowers (Solanum dulcamara and S. rostratum). Our study does not support the hypothesis that the dearth of buzz‐pollinating flies is caused by their inability to produce vibrations of sufficient amplitude. We discuss alternative hypotheses to explain why most flies do not engage in buzz pollination and suggest that the lack of buzz‐pollinating flies might be best explained through their life history.

Hoverflies (Diptera: Syrphidae) of El Ventorrillo Biological Station, Madrid province, Spain: a perspective from a late twentieth century inventory

Temporal comparisons of a site's biodiversity depend on the availability of at least two asynchronous data sets on a bioindicator group. The Sierra de Guadarrama, a mountain range in central Spain has a high biodiversity and representative sites such as El Ventorrillo Biological Station (Madrid province) play an important role in research and monitoring of the Sierra biodiversity. Although unevenly and randomly, hoverflies of the Sierra de Guadarrama have been surveyed for decades, but never at El Ventorrillo. This important group of pollinators, aphid predators and bioindicators was sampled with a Malaise trap at El Ventorrillo from June 1989 to June 1990. A total of 51 species were identified (20 spp. of Eristalinae and 31 spp. of Syrphinae), 22 of which were new to the Sierra de Guadarrama and 17 to the Madrid province. The genera Brachypalpus and Didea were also new to the Madrid province. The Sierra de Guadarrama now has 126 species recorded and the Madrid province 150. Within the Sierra de Guadarrama, El Ventorrillo becomes the second locality in number of hoverfly species recorded after El Escorial (64 spp.). In the Malaise trap catch, hoverflies with zoophagous larvae had a higher representation than those of other guilds, both in species richness and abundance. The results provided here for El Ventorrillo represent a baseline for future biodiversity studies at this site with a similar experimental design, for example, to detect changes in hoverfly diversities along time.

Seasonality of predatory insects (Diptera: Syrphidae and Asilidae) in pasture monoculture and silvopastoral systems from Southeast Brazil

In this long-term study we evaluated the diversity and seasonality of predatory insects (Diptera: Syrphidae and Asilidae) in Brachiaria decumbens monoculture and silvopastoral systems in Southeast Brazil. The study was conducted in Coronel Pacheco municipality, Minas Gerais state, Brazil, between February 2010 and January 2015. Insects were collected with malaise traps installed in both monoculture and silvopastoral systems. Specimen abundance, family diversity, seasonality assessed by circular analysis, the degrees of association between specimen number and climatic variables measured by Spearman’s correlation, and the constancy and similarities of Syrphidae and Asilidae were analyzed in the monoculture and silvopastoral systems. Eleven species of hoverflies (Diptera: Syrphidae) were collected, five and three of which were exclusive to the silvopasture and monoculture, respectively. The number of specimens within the monoculture was significantly greater than that in the silvopasture. Twenty-four species of robber flies (Diptera: Asilidae) were collected, two of which were exclusive to the monoculture and eight to the silvopasture. The abundance of robber flies in the silvopasture was not significantly different from that in the monoculture. Syrphidae diversity was greater in the monoculture and was not significantly different from robber fly family diversity. Circular analysis revealed seasonality, with the distribution grouped during dry periods for hoverflies and dispersed for robber flies. Most hoverflies and robber flies were accidental in each of the systems. Further studies on the capacity of these predator species to act as biological control agents of pasture pests are required. This study presents important and promising results for understanding the dynamics of the Syrphidae and Asilidae community in monoculture and silvopastoral systems in Brazil.

New data on the hoverflies of Morocco (Diptera, Syrphidae) with faunistic and bibliographical inventories.

All published records of 148 species of hoverflies from Morocco are reviewed and appropriate literature references, new locality records, and relevant comments are provided for each species. The list is supplemented with records from new field surveys. Two species, Eumerus obliquus (Fabricius, 1805) and Orthonevra brevicornis Loew, 1843 are recorded for the first time in Morocco. The new checklist comprises 150 nominal species from three subfamilies, 14 tribes, and 49 genera.

Corrigendum

New PhytologistVolume 229, Issue 2 p. 1177-1177 CorrigendumFree Access Corrigendum This article corrects the following: Cypripedium subtropicum (Orchidaceae) employs aphid colony mimicry to attract hoverfly (Syrphidae) pollinators Hong Jiang, Ji-Jun Kong, Hsin-Chun Chen, Zhen-Yong Xiang, Wei-Ping Zhang, Zhou-Dong Han, Pei-Chun Liao, Yung-I Lee, Volume 227Issue 4New Phytologist pages: 1213-1221 First Published online: May 22, 2020 First published: 24 September 2020 https://doi.org/10.1111/nph.16889 Author for correspondence: Yung-I Lee Tel:+886 4 23226940 ext. 153 Email:[email protected] AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL New Phytologist 227 (2020), 1213–1221, doi: 10.1111/nph.16623 Since its publication, the authors of Jiang et al. (2020) have brought to our attention an error in their article. The species of hoverfly detailed in the legend Fig. 2(a,b) and (c,d) were transposed. The correct Fig. 2 legend is shown below. Fig. 2Open in figure viewerPowerPoint A pollination system in Cypripedium subtropicum. (a) Eupeodes confrater eating hair tufts. Bar, 3 mm. (b) The body of E. confrater has contacted the anther. Bar, 3 mm. (c) Eristalinus arvorum eating hair tufts. Bar, 3 mm. (d) The body of E. arvorum has contacted the anther. Bar, 3 mm. (e) Dissected flower with half the labellum removed. The dotted line indicates the pollination route and direction of fly movement. Bar, 10 mm. (f) Cryo-scanning electron microscopy (SEM) image of a few cells from white hair tufts (arrow) on the mouthparts of a trapped hoverfly. Bar, 100 μm. We apologize to our readers for this mistake. Reference Jiang H, Kong J-J, Chen H-C, Xiang Z-Y, Zhang W-P, Han Z-D, Liao P-C, Lee Y-I. 2020. Cypripedium subtropicum (Orchidaceae) employs aphid colony mimicry to attract hoverfly (Syrphidae) pollinators. New Phytologist 227: 1213– 1221. Volume229, Issue2January 2021Pages 1177-1177 FiguresReferencesRelatedInformation

Wild bees and hoverflies respond differently to urbanisation, human population density and urban form

While urbanisation contributes to global biodiversity declines, flower-rich urban habitats may provide beneficial pollinator habitats. We investigated the potential of urban residential areas to contribute to pollinator diversity by analysing wild bee and hoverfly species richness and composition of species assemblages of summer-active species, sampled in 53 gardens across urban and rural landscapes of Malmö, the regional capital of Sweden’s southernmost county. Species richness differed between urban and rural gardens, and between four urban residential types (ranging from low human density and high vegetation cover, to high human density and low vegetation cover), and taxonomic groups responded differently. Solitary bee species richness was higher in urban than rural gardens, driven by a higher richness in low-density urban gardens compared to both high-density urban gardens and rural gardens. In contrast, bumblebee species richness was higher in rural than urban gardens, whereas differences among the urban types were less clear. Hoverfly species richness was consistently higher in rural gardens than any urban garden type. Species richness of all groups was negatively related to human population density at the landscape scale (radius 500 m), but unrelated to vegetation cover. This indicates that population density affects pollinator habitat quality through associated green space management and design. Rural and urban wild bee species assemblages consisted of different species (significant species turnover), whereas urban hoverfly assemblages were a subset of rural ones (significant nestedness). Species nestedness of hoverflies, but not bees, increased with human population density. We show that urban areas can complement the regional wild bee species pool, mainly caused by large variation in tenure and management at small spatial scales, while urbanisation drives a systematic loss of hoverfly species. We suggest alternatives to improve dense residential areas for pollinators.

New Records of Hoverflies (Diptera, Syrphidae) from Ukraine. V. Summary

Ten additional species of hover flies of the subfamilies Eristalinae and Syrphinae are recorded from Ukraine for the first time: Cheilosia bergenstammi Becker, 1894, C. fraterna (Meigen, 1830), C. nebulosa Verrall, 1871, C. pascuorum Becker, 1894, C. uviformis Becker, 1894, Pelecocera scaevoides (Fallén, 1817), Dasysyrphus pauxillus (Williston, 1887), Epistrophe cryptica Doczkal and Schmid, 1994, Melangyna quadrimaculata (Verrall, 1873), and Xanthogramma dives (Rondani, 1857). Distributions of these species are summarized and species diagnoses are provided. Updated key to Cheilosia males of the group D sensu Becker (1894), which have tibiae with pale parts, is provided.

Odorant Binding Proteins and Chemosensory Proteins in Episyrphus balteatus (Diptera: Syrphidae): Molecular Cloning, Expression Profiling, and Gene Evolution.

Aphidophagous syrphids (Diptera: Syrphidae) are important insects in agroecosystems for pollination and biological control. Insect chemoreception is essential for these processes and for insect survival and reproduction; however, molecular determinants is not well understood for these beneficial insects. Here, we used recent transcriptome data for the common hoverfly, Episyrphus balteatus, to characterize key molecular components of chemoreception: odorant-binding proteins (OBPs) and chemosensory proteins (CSPs). Six EbalCSPs and 44 EbalOBPs were cloned from this species, and sequence analysis showed that most share the characteristic hallmarks of their protein family, including a signal peptide and conserved cysteine signature. Some regular patterns and key conserved motifs of OBPs and CSPs in Diptera were identified using the online tool MEME. Motifs were also compared among the three OBP subgroups. Quantitative real-time PCR (qRT-PCR) showed that most of these chemosensory genes were expressed in chemosensory organs, suggesting these genes have chemoreceptive functions. An overall comparison of the Ka/Ks values of orthologous genes in E. balteatus and another predatory hoverfly species to analyze the evolution of these olfactory genes showed that OBPs and CSPs are under strong purifying selection. Overall, our results provide a molecular basis for further exploring the chemosensory mechanisms of E. balteatus, and consequently, may help us to understand the tritrophic interactions among plants, herbivorous insects, and natural enemies.

Quantifying pollination efficiency of flower-visiting insects and its application in estimating pollination services for common buckwheat

Pollination services provided by managed honey bee and wild pollinators are essential for a range of crops. Pollination services can be measured as species-related services, which can be quantified by the combination of each species’ pollination efficiency and their abundance, as well as harvest-related services, which can be quantified by the pollinator exclusion method. Species-related pollination services are poorly documented and have never been directly compared to harvest-related services. Here, we aimed to quantify the pollination efficiency for common flower-visiting species of common buckwheat (Fagopyrum esculentum) and to scale it up to estimate pollination services. We assessed pollination efficiency by single-visit pollen deposition and visitation rate for common flower-visiting insect species. We monitored the abundance of these species during the entire flowering period across seven sites, where pollinator exclusion treatments were undertaken by caging. In total, we observed 27 flower-visiting species and calculated the pollination efficiency of 17 species. We found that flower-visiting species had different capabilities in transferring compatible pollen grains for two flower morphs and different visitation rates. The estimated pollination efficiency was highest for two honey bee species (Apis mellifera and A. cerana), followed by the hoverfly species (Eristalis tenax), and wasp species (Tiphia vernalis). Species-related pollination services estimated by pollination efficiency and abundance showed a strong positive relationship with harvest-related services, which were estimated by the pollinator exclusion method. Our results suggest that to achieve substantial pollination services for common buckwheat, it is important to maintain sufficient managed honey bees, particularly in areas lacking highly efficient wild pollinators species. Our study also suggests that it is possible to estimate pollination services by scaling up the pollination efficiency of common flower-visiting insects. We provide recommendations for the application of this technique.

Can anthophilous hover flies (Diptera: Syrphidae) discriminate neonicotinoid insecticides in sucrose solution?

Understanding how neonicotinoid insecticides affect non-target arthropods, especially pollinators, is an area of high priority and popular debate. Few studies have considered how pollinators interact and detect neonicotinoids, and almost none have examined for these effects in anthophilous Diptera such as hover flies (Syrphidae). We investigated behavioral responses of two species of hover flies, Eristalis arbustorum L. (Eristalinae) and Toxomerus marginatus Say (Syrphinae), when given a choice between artificial flowers with uncontaminated sucrose solution and neonicotinoid-contaminated (clothianidin) sucrose solution at field-realistic levels 2.5 ppb (average) and 150 ppb (high). We examined for 1) evidence that wild-caught flies could detect the insecticide gustatorily by analyzing amount of time spent feeding on floral treatments, and 2) whether flies could discriminate floral treatments visually by comparing visitation rates, spectral reflectance differences, and hover fly photoreceptor sensitivities. We did not find evidence that either species fed more or less on either of the treatment solutions. Furthermore, T. marginatus did not appear to visit one of the flower choices over the other. Eristalis arbustorum, however, visited uncontaminated flowers more often than contaminated flowers. Spectral differences between the flower treatments overlap with Eristalis photoreceptor sensitivities, opening the possibility that E. arbustorum could discriminate sucrose-clothianidin solution visually. The relevance of our findings in field settings are uncertain but they do highlight the importance of visual cues in lab-based choice experiments involving insecticides. We strongly encourage further research in this area and the consideration of both behavioral responses and sensory mechanisms when determining insecticidal impacts on beneficial arthropods.

Pollinator Specific Richness and Their Interactions With Local Plant Species: 10 Years of Sampling in Mediterranean Habitats.

In the context of global pollinator decline, little is known about the protection status and ecology of many species. This lack of knowledge is particularly important for Mediterranean protected areas that harbor diverse pollinator communities and are subject to considerable anthropogenic pressures. Calanques National Park (85 km2), which is located near Marseille (France), is dominated by Mediterranean low-vegetation habitats, such as phrygana and scrublands. These habitats offer favorable conditions for pollinator species due to the important amount of floral resources. Within a 10-yr period, we recorded bee (Hymenoptera: Apoidea: Anthophila), hover fly (Diptera: Syrphidae), and bee fly (Diptera: Bombyliidae) species and their interactions with the local flora through 10 field campaigns. We caught 250 pollinator species, including 192 bees, 38 hover flies, and 20 bee flies, for a total of 2,770 specimens. We recorded seven threatened bees (six near threatened and one endangered). Among the bee species, 47.9% were below-ground nesting species, and 54.7% were generalist species. Analysis of the pollination network showed that generalist and specialist pollinators do not share the same floral resources. The Cistaceae plant family (Malvales: Cistaceae) acted as a central node in the plant-pollinator network, interacting with 52 different pollinator species, which shows the importance of large open flowers that could be easily visited by both short and long-tongued pollinators in Mediterranean habitats. The occurrence of pollinator species and their ecological traits should strongly contribute to reinforcing the available information to provide or ameliorate the conservation statuses determined by IUCN Red List.

Pollinator emerging from extensive green roofs: wild bees (Hymenoptera, Antophila) and hoverflies (Diptera, Syrphidae) in Geneva (Switzerland)

By the end of 2020, 75% of the Swiss population will live in cities. The urban densification will result in habitat and biodiversity loss. One solution to mitigate this loss in urban environments is the implementation of green roofs that are now recognised as a tool for the maintenance of epigeal and aerial arthropods. Green roofs can provide various services such as pollination and food supply for insects and various arthropods (e.g. arachnids) and animals (e.g. birds). The objective of this study was to evaluate the diversity of pollinating insects emerging from urban green roofs. Wild bees (Hymenoptera) and hoverflies (Diptera) were sampled using emergence traps on six extensive green roofs in the urban area of Geneva (Switzerland), from March to August 2017. Five species of wild bees and two species of hoverflies were identified: Lasioglossum morio (Halictidae) and Sphaerophoria scripta (Syrphidae) are the only two species considered as emerging from green roofs in our study. Ecological traits of these two species indicated generalists, well adapted to xero-thermophilic conditions.

Protected areas and prime hoverfly areas: Safe haven for hoverflies or not?

AbstractThe efficiency of protected areas (PAs) has often been questioned due to global decline of biodiversity. Invertebrates, especially insects, have been historically underrepresented in conservation studies. Our study focuses on hoverflies, an important group of insect pollinators and proven to be good bioindicators. Research was focused in Serbia, one of Europe's hotspots of hoverfly diversity, with a long tradition of hoverfly research, which provided sufficient information for achieving our aims: identifying areas of high hoverfly diversity, evaluating the efficiency of PAs and prime hoverfly areas (PHAs) in the conservation of hoverflies, determining how well they cover the distribution of hoverfly species, especially those of conservation concern, and testing the importance of the size of the area for conservation of hoverfly diversity. We applied weighting of the species to help stress the importance of species of conservation concern. The results indicated that PHAs cover the areas with high hoverfly diversity better than PA networks, especially when it comes to species of conservation concern. Generalized linear model results showed that the area size was a significant predictor of number of species in both PA and PHA. This indicates that area size is key when designating new areas important for conservation, but there are also other factors that need to be taken into account, such as habitat quality or suitability. Studies like this are useful in aiding designation of new areas important for conservation of certain species and in identifying sampling gaps, which could potentially aim future research in that direction.

Flies on vacation: evidence for the migration of Australian Syrphidae (Diptera)

1. Hover flies (Syrphidae: Diptera) are a cosmopolitan group of insects that provide important ecosystem services including pollination and pest control. The seasonal migration of hover flies is probably best known in Europe, but it remains unstudied in many other parts of the world.2. Australia is believed to be home to around 160 hover fly species, some of which are common in urban and agricultural environments. The current evidence for hover fly migration in Australia is scarce and anecdotal, yet migration may be critical to the success of pollination and the biological control of aphids.3. In this study, species occurrence records from an online biodiversity database (Atlas of Living Australia) were used to look for evidence of migratory behaviours in all Australian hover flies with more than 200 occurrence records.4. Four of the 10 species displayed seasonal changes in their distribution consistent with migration, including Australia's two most abundant species: Melangyna viridiceps and Simosyrphus grandicornis. This work is an important first step in understanding the prevalence of migration in Australian hover flies. However, confirmation of our findings requires additional evidence to rule out other plausible explanations for the observed patterns.5. Based on changes in summer and winter latitudinal distribution, it is estimated that some Australian hover flies may make annual migrations of 400–1800 km.6. This work suggests that the management of beneficial insects requires consideration of factors at both local and continental scales, as landscape use changes may have an impact on ecosystem services delivered hundreds of kilometres away.

New records of hover flies (Diptera, Syrphidae) from Ukraine. IV

Six additional species of hover flies of the subfamily Eristalinae are recorded fromUkraine for the first time: Criorhina pachymera Egger, 1858, Hammerschmidtia ferruginea (Fallén, 1817),Melanogaster parumplicata (Loew, 1840), Orthonevra erythrogona (Malm, 1863), Sphiximorpha garibaldiiRondani, 1860, and Temnostoma angustistriatum Krivosheina, 2002. Distributions of these species aresummarized and species diagnoses are provided. Updated key to males of the European species of thegenus Melanogaster including a little-known M. jaroslavensis (Stackelberg, 1922) is proposed.   &nbsp