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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]

Abstract Native insect flower visitors can be important contributors to crop pollination, yet little is known of their pollination abilities and the resources (habitat) they need to be supported within crop agroecosystems. Here, we compared the abundance and pollination abilities of the golden drone fly (Eristalinus punctulatus) to the European honey bee (Apis mellifera) in hybrid carrot crop fields known to produce variable seed yields in regional New South Wales, Australia. We further observed the egg‐laying behaviours of female golden drone flies at a commercial berry orchard to provide insight into the habitat needs of this species. In hybrid carrot crop fields, golden drone flies were far less abundant flower visitors than European honey bees; however, these flies deposited more carrot pollen grains on average (8.21 ± 3.04 SE) onto carrot flowers than European honey bees (3.45 ± 1.06 SE). Both insects also deposited pollen onto a similar number of carrot flowers (pollinated) per visit (about 2 out of 18). Golden drone flies were observed laying eggs within masses of discarded red raspberry plant roots and soil (root balls) at a commercial berry orchard. The natural habitat utilised by these flies, as well as their egg‐laying behaviours, were described for the first time. Our results indicate that golden drone flies are effective pollinators of hybrid carrot crop plants. The habitat that these flies utilised to lay eggs (discarded plants and water) is cheap and commonly found in crop agroecosystems. Therefore, we recommend placing this low‐cost habitat within, or nearby, crop fields as a potential management practice to support the lifecycle needs of golden drone flies and other non‐bee pollinators.

Although the importance of natural habitats to pollinator diversity is widely recognized, the value of forests to pollinating insects has been largely overlooked in many parts of the world. In this review, we (i) establish the importance of forests to global pollinator diversity, (ii) explore the relationship between forest cover and pollinator diversity in mixed‐use landscapes, and (iii) highlight the contributions of forest‐associated pollinators to pollination in adjacent crops. The literature shows unambiguously that native forests support a large number of forest‐dependent species and are thus critically important to global pollinator diversity. Many pollinator taxa require or benefit greatly from resources that are restricted to forests, such as floral resources provided by forest plants (including wind‐pollinated trees), dead wood for nesting, tree resins, and various non‐floral sugar sources (e.g. honeydew). Although landscape‐scale studies generally support the conclusion that forests enhance pollinator diversity, findings are often complicated by spatial scale, focal taxa, landscape context, temporal context, forest type, disturbance history, and external stressors. While some forest loss can be beneficial to pollinators by enhancing habitat complementarity, too much can result in the near‐elimination of forest‐associated species. There is strong evidence from studies of multiple crop types that forest cover can substantially increase yields in adjacent habitats, at least within the foraging ranges of the pollinators involved. The literature also suggests that forests may have enhanced importance to pollinators in the future given their role in mitigating the negative effects of pesticides and climate change. Many questions remain about the amount and configuration of forest cover required to promote the diversity of forest‐associated pollinators and their services within forests and in neighbouring habitats. However, it is clear from the current body of knowledge that any effort to preserve native woody habitats, including the protection of individual trees, will benefit pollinating insects and help maintain the critical services they provide. [ABSTRACT FROM AUTHOR]

Two new species of Syrphidae, Orthonevra arcana Ricarte and Nedeljković, 2022 and Pelecocera caledonica (Collin, 1940), are added to the list of the Belgian fauna. The first is a freshwater wetland species that was recently described from Spain and that is here reported more than 1000 km more northerly in Wallonia and Flanders. It is clearly a rare species in Belgium with two populations known so far. Checking Dutch and German collections so far did not yield any O. arcana. The second is a typical pine forest and heathland species restricted to open old Pinus forest with associated mycorrhiza. This species is extremely rare now within Western Europe and is also very rare at its Belgian site. [ABSTRACT FROM AUTHOR]

Flower flies (Diptera: Syrphidae) are one of the most species‐rich dipteran families and provide important ecosystem services such as pollination, biological control of pests, recycling of organic matter and redistributions of essential nutrients. Flower fly adults generally feed on pollen and nectar, but their larval feeding habits are strikingly diverse. In the present study, high‐throughput sequencing was used to capture and enrich phylogenetically and evolutionary informative exonic regions. With the help of the baitfisher software, we developed a new bait kit (SYRPHIDAE1.0) to target 1945 CDS regions belonging to 1312 orthologous genes. This new bait kit was successfully used to exon capture the targeted loci in 121 flower fly species across the different subfamilies of Syrphidae. We analysed different amino acid and nucleotide data sets (1302 loci and 154 loci) with maximum likelihood and multispecies coalescent models. Our analyses yielded highly supported similar topologies, although the degree of the SRH (global stationarity, reversibility and homogeneity) conditions varied greatly between amino acid and nucleotide data sets. The sisterhood of subfamilies Pipizinae and Syrphinae is supported in all our analyses, confirming a common origin of taxa feeding on soft‐bodied arthropods. Based on our results, we define Syrphini stat.rev. to include the genera Toxomerus and Paragus. Our divergence estimate analyses with beast inferred the origin of the Syrphidae in the Lower Cretaceous (125.5–98.5 Ma) and the diversification of predatory flower flies around the K–Pg boundary (70.61–54.4 Ma), coinciding with the rise and diversification of their prey. [ABSTRACT FROM AUTHOR]

The article, based on materials from the author's collections for 2017−2022 and partly on the collections of the Samarkand State University (Samarkand) and the Samarkand Museum of Local Lore, provides the first data on the distribution of 79 species of syrphids from 3 subfamilies in the Western part of the Zarafshan ridge. Ten species have been recorded for the first time in Uzbekistan: Chrysotoxum kirghizorum Peck, 1974, Eupeodes asiaticus (Peck, 1972), Scaeva dignota (Rondani, 1857), Syrphus rectus Osten Sacken, 1875, Xanthogramma hissarica Violovitsh, 1975, Chrysogaster cemiteriorum (Linnaeus, 1758), Cheilosia aerea Dufour, 1848, Ch. lola Zimina, 1970, Ch. stackelbergi Barkalov & Peck, 1994, and Volucella bella Barkalov, 2003. In addition, one genus – Neocnemodon Goffe, 1944 recorded for the first time for Uzbekistan.

Milesia cretica Bot & van Steenis sp. nov. is described from the Island of Crete, Greece. An identification key to all the European species of Milesia Latreille, 1804 is provided, together with DNA barcodes to distinguish the new species.

A new species for the Belgian fauna, Platycheirus complicatus (Becker, 1889), has been found in the Hautes Fagnes, near the German border. This species belongs to the group of forest dwelling species and has been found in forest glades and along forest tracks in Beech and spruce forest. Platycheirus complicatus has up to three closely related and extremely similar species within Europe and North America, and it remains to be solved whether they are all valid species. This species is not always easily identified with current keys and some additional differential diagnosis characters are provided. [ABSTRACT FROM AUTHOR]

Syrphid flies (Diptera: Syrphidae) are a cosmopolitan group of flower-visiting insects, though their diversity and importance as pollinators is understudied and often unappreciated. Data on 1,477 Syrphid occurrences and floral associations from three years of pollinator collection (2017-2019) in the Southern Illinois region of Illinois, United States, are here compiled and analyzed. We collected 69 species in 36 genera off of the flowers of 157 plant species. While a richness of 69 species is greater than most other families of flower-visiting insects in our region, a species accumulation curve and regional species pool estimators suggest that at least 33 species are yet uncollected. In order to further the understanding of Syrphidae as pollinators in the Southern Illinois region, we produced a NMDS ordination of floral associations for the most common syrphid species. The NMDS did not sort syrphid species into discrete ecological guilds, and syrphid floral associations generally fit those predicted by traditional pollination syndromes. We also conducted a preliminary analysis of the pollen-carrying capacity of different syrphid taxa, which found several Eristalis species to carry pollen loads comparable to the European Honey Bee, Apis mellifera, and showed significant differences in the pollen-carrying capacity of various syrphid species. Notably, the extremely common genus Toxomerus and other small Syrphinae species carried very little pollen, while large and pilose Eristalinae species carried large pollen loads.

Preimaginal morphology of Austroscaeva occidentalis (Shannon, 1927) is described for the first time, and the morphology of larvae and pupae of Dioprosopa clavata (Fabricius, 1794) is updated based on material obtained from captive rearing of wild females from Argentina and Venezuela, respectively. We describe the morphology of the third instar larva, head skeleton and puparium using optical microscopy, cryo‐scanning and scanning electron microscope. The immature stages of both New World flower fly species are analysed and compared with the known preimaginal morphology of other taxa that belong to the evolutionary lineage of Eupeodes‐Scaeva, where Austroscaeva Láska, Mazánek & Mengual, 2018, and Dioprosopa Hull, 1949, form a Neotropical radiation within, together with the genus Notosyrphus Vockeroth, 1969. Larvae of all members of this lineage have abdominal segments 5 and 6 with the tips of the locomotory prominences facing posteriorly, and the anal segment with a characteristic U‐shaped grasping organ. Two other larval synapomorphies of this group of genera are the presence of metathoracic setae accompanying ventral sensilla, and the abdominal segments 1–7 with an extra lobe on each locomotory prominence. These two last characters cannot be assessed for Macrosyrphus Matsumura, 1917, and Lapposyrphus Dušek & Láska, 1967, based on published information on larval descriptions. Despite a similar colouration pattern of the fully grown larvae, larval morphology of A. occidentalis and D. clavata are quite distinct. The preimaginal morphology of A. occidentalis has a mixture of morphological characters from the taxa Scaeva Fabricius, 1805, Semiscaeva Kuznetzov, 1985, and Dioprosopa. The larvae of D. clavata show several unique diagnostic features, such as the presence of a slightly serrate outline due to the great development of the segmental spines and a pinnate ornamentation of the setae of its dorsal and dorsolateral sensilla. Regarding their biological cycle, the length of the preadult stages of A. occidentalis is almost 5 days longer than the length observed for D. clavata. In addition, new DNA barcodes are provided for A. occidentalis. [ABSTRACT FROM AUTHOR]

New records of flower flies (Diptera, Syrphidae) from Iran are reported. The species Criorhina talyshensis (Stackelberg) is reported for the first time from Iran, and a female of Caliprobola aurea Sack from Mazandaran Province represents the second record of the species from this country. DNA barcodes are provided for both species, together with images and an identification key to Caliprobola species. [ABSTRACT FROM AUTHOR]

Abstract Syrphid flies, Ischiodon scutellaris (Fabricius) and Episyrphus balteatus (DeGeer), are among the most common aphidophagous species in wheat growing areas of Punjab, Pakistan. Exploit predatory species efficiently in any biological control program requires an in-depth understanding of predator and prey interactions. The present study was conducted aiming to explore and compare the predatory potential of these predatory species against the wheat aphid, Schizaphis graminum (Rondani) along with their relative fitness at different temperatures in terms of duration of lifecycle stages under laboratory conditions. The shortest egg and pupal durations were observed at 33 °C, followed by 27 and 23 °C. Females of both species had longer life span (20.4 and 22.4 days) compared to the respective males (17.2 and 16.2 days). The pupal stage for I. scutellaris was significantly shorter than for E. balteatus at different temperatures; but statistically insignificant differences were found for any other life stage. The larvae of I. scutellaris consumed significantly more aphids (438.16) than E. balteatus (398.37) during their larval life span, and this difference was significant during the 1st and 3rd instars. However, the average daily prey intake of both species was found similar until the 10th day after hatching, and thereafter, I. scutellaris consumed significantly higher numbers of aphids/day. Obtained results may offer a baseline data for future conservation studies on biological control of aphids.

Context: To safeguard insect pollinators and their pollination services, we need to understand how landscape structure regulates the distribution of resources that sustain pollinator populations. However, evidence of how pollinator communities benefit from the variety of resources distributed across different habitat types is scarce. Objectives: To explore complementary resource provision, we conducted a field study to examine the resources available to pollinators in fruit orchards and woody semi-natural habitat. Methods: We studied 13 landscapes containing both habitat types in Flanders, Belgium. In every habitat element, we surveyed nesting resources, floral resources and wild pollinators (i.e. wild bees and hover flies) during three consecutive time periods in the season (once before- and twice after mass-flowering of the fruit orchards). Results: We concluded that the composition of nesting resources for wild bees was clearly different between both habitat types. Woody semi-natural habitat also provided more diverse- and a higher cover of floral resources compared to fruit orchards. In addition, the composition of these floral resources became more and more distinct between the two habitat types as the season progressed. Based on the plant − pollinator network we identified key plant species for inclusion in management schemes to support pollinators. Conclusions: Our study highlights that fruit orchards and woody semi-natural habitat provide a set of different, complementary resources during the flight season, for pollinating insects. Due to the higher diversity and abundance of resources in woody semi-natural habitat, conservation of woody semi-natural habitat is essential for the support of pollinators in agricultural landscapes. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships of the Sphaerophoria lineage (Sphaerophoria Le Peletier & Audinet-Serville and related genera) were inferred based on molecular characters, with the specific aim to infer the phylogenetic placement of the Afrotropical Sphaerophoria species and Loveridgeana beattiei van Doesburg & van Doesburg. Three molecular markers were used, i.e., the mitochondrial protein-coding gene cytochrome c oxidase subunit I (COI) and the nuclear 28S and 18S ribosomal RNA genes. The Sphaerophoria lineage genera Exallandra Vockeroth and Loveridgeana were resolved within the genus Sphaerophoria, and the Indomalayan Eosphaerophoria Frey was placed sister to Citrogramma Vockeroth, both related to a large species radiation from the New World. Fazia Shannon and Allograpta Osten Sacken were recovered as non-monophyletic. Our results recovered two different Fazia clades with dissimilar natural history resulted from our analyses, and Allograpta species were resolved into two clades, one with Nearctic and Neotropical species and a second clade with species from Oceanian, Indomalayan and Afrotropical Regions. Exallandra is considered a subgenus of Sphaerophoria, S. (Exallandra) stat. rev., and Sphaerophoria cinctifacies (Speiser) n. comb. a member of this subgenus together with S. loewii Zetterstedt. A new Sphaerophoria subgenus is designated S. (Loveridgeana) stat. rev. to include S. beattiein. comb. and the South African species, i.e., S. quadrituberculata Bezzi, S. retrocurva Hull, and S. aff. retrocurva. Based on their phylogenetic distinctiveness, functional traits, and ecological relevance we do recommend further ecological study and protection efforts for this Afrotropical group of pollinators. [ABSTRACT FROM AUTHOR]

The flower fly genus Afrosyrphus Curran, 1927 (Diptera, Syrphidae) is revised and a new species, Afrosyrphus schmuttereri sp. nov., from Kenya and Uganda is described. Diagnoses, illustrations, DNA barcodes and known distributional data are provided for the two species of this genus, as well as an identification key. A critical review of the published literature is also provided.

Abstract Eumerus Meigen, 1823 is a very speciose genus of flower flies from the Eastern Hemisphere. Several reports of introduced species of this genus in the Americas have been recorded since early in the twentieth century, with a present list of six species recorded to date from the Americas and the US territory of Hawaii. In this paper we give new geographical records for the African-native species Eumerus obliquus (Fabricius, 1805), which reflect the expansion of this fly through Brazil and Paraguay along the last twenty years. At the same time, we report a second species from Paraguay, Eumerus aurifrons (Wiedemann, 1824), being this the first Western Hemisphere record for this Asian-native species. We finally provide an identification key to all of the species of Eumerus presently known from the Americas and Hawaii.

Syrphid flies (Diptera: Syrphidae) are a cosmopolitan group of flower-visiting insects, though their diversity and importance as pollinators is understudied and often unappreciated. Data on 1,477 Syrphid occurrences and floral associations from three years of pollinator collection (2017-2019) in the Southern Illinois region of Illinois, United States, are here compiled and analyzed. We collected 69 species in 36 genera off of the flowers of 157 plant species. While a richness of 69 species is greater than most other families of flower-visiting insects in our region, a species accumulation curve and regional species pool estimators suggest that at least 33 species are yet uncollected. In order to further the understanding of Syrphidae as pollinators in the Southern Illinois region, we produced a NMDS ordination of floral associations for the most common syrphid species. The NMDS did not sort syrphid species into discrete ecological guilds, and syrphid floral associations generally fit those predicted by traditional pollination syndromes. We also conducted a preliminary analysis of the pollen-carrying capacity of different syrphid taxa, which found several Eristalis species to carry pollen loads comparable to the European Honey Bee, Apis mellifera, and showed significant differences in the pollen-carrying capacity of various syrphid species. Notably, the extremely common genus Toxomerus and other small Syrphinae species carried very little pollen, while large and pilose Eristalinae species carried large pollen loads. [ABSTRACT FROM AUTHOR]

The morphological similarities between five new large Argentinomyia species and Talahua fervida Fluke are characterized and presented. Six new species of Argentinomyia (10-12 mm long) are described: Argentinomyia andina Montoya & Wolff, sp. nov. (Colombia), Argentinomyia choachi Montoya, sp. nov. (Colombia), Argentinomyia quimbaya Montoya & Wolff, sp. nov. (Colombia), Argentinomyia huitepecensis Montoya, sp. nov. (México), Argentinomyia puntarena Montoya, sp. nov. (Costa Rica), and Argentinomyia talamanca Thompson, sp. nov. (Costa Rica). The genus Talahua Fluke is re-diagnosed and, Talahua fervida redescribed. A taxonomic key and a comparison of diagnostic characters are presented. Photographs of head, abdominal and wing maculae patterns, as well as illustrations of male genitalia are provided for species identification. [ABSTRACT FROM AUTHOR]

A checklist of the Syrphidae species of the Republic of Georgia is presented. New hover fly (Diptera: Syrphidae) records from Georgia are provided as a result of field work conducted in 2018. At the same time, published syrphid records for the country are here reviewed and updated. A total of 357 species of hoverflies are now documented from Georgia, 40 of which are reported for the first time. Moreover, DNA barcodes were sequenced for 238 specimens, representing 74 species from this country. [ABSTRACT FROM AUTHOR]

Rat-tailed larvae of the syrphid species Palpada scutellaris (Fabricius, 1805) are documented causing an enteric human myiasis in Costa Rica. This is the first time that the genus Palpada is recorded as a human myiasis agent. We report a 68-year-old woman with intestinal pain and bloody diarrhea with several live Palpada larvae present in the stool. Using molecular techniques (DNA barcodes) and both electronic and optical microscopy to study the external morphology, the preimaginal stages of the fly were unambiguously identified. An identification key to all syrphid genera actually known as agents of human and animal myiases is provided for larvae, puparia, and adults. Moreover, a critical world review of more than 100 references of Syrphidae as myiasis agents is also given, with emphasis on the species with rat-tailed larvae. [ABSTRACT FROM AUTHOR]

A new species of Eumerus, Eumerus druk Smit sp. nov., is described from Bhutan. This species belongs to the bactrianus subgroup of the strigatus species group. Seven species are currently known within this subgroup: four European, one of which is also found in the Near East, and three more only known from Tajikistan. The new species extends this disjunct distribution to the east by at least 2,000 km, stretching far beyond the reported Turano-Mediterranean region and into the Himalayas. A diagnosis and a key to all Central and Eastern Palaearctic species of the Eumerus bactrianus subgroup are provided. [ABSTRACT FROM AUTHOR]

A body of an unknown adult female was found within a shallow burial ground in Malaysia whereas the skull was exposed and visible on the ground. During autopsy examination, nine insect larvae were recovered from the interior of the human skull and subsequently preserved in 70% ethanol. The larvae were greyish in appearance, each with a posterior elongated breathing tube. A week after the autopsy, more larvae were collected at the burial site, and some of them were reared into adults. Adult specimens and larvae from the skull and from the burial site were sequenced to obtain DNA barcodes. Results showed all adult flies reared from the burial site, as well as the larvae collected from the skull were identified as Eristalinus arvorum (Fabricius, 1787) (Diptera: Syrphidae). Here, we report the colonization of E. arvorum larvae on a human corpse for the first time. [ABSTRACT FROM AUTHOR]

Background This paper describes 11 of 18 new species recognised in the recent book, "Field Guide to the Flower Flies of Northeastern North America". Four species are omitted as they need to be described in the context of a revision (three Cheilosia and a Palpada species) and three other species (one Neoascia and two Xylota) will be described by F. Christian Thompson in a planned publication. Six of the new species have been recognised for decades and were treated by J. Richard Vockeroth in unpublished notes or by Thompson in his unpublished but widely distributed "A conspectus of the flower flies (Diptera: Syrphidae) of the Nearctic Region". Five of the 11 species were discovered during the preparation of the Field Guide. Eight of the 11 have DNA barcodes available that support the morphology. New information New species treated in this paper include: Anasimyia diffusa Locke, Skevington and Vockeroth (Smooth-legged Swamp Fly), Anasimyia matutina Locke, Skevington and Vockeroth (Small-spotted Swamp Fly), Brachyopa caesariata Moran and Skevington (Plain-winged Sapeater), Brachyopa cummingi Moran and Skevington (Somber Sapeater), Hammerschmidtia sedmani Vockeroth, Moran and Skevington (Pale-bristled Logsitter), Microdon (Microdon) scauros Skevington and Locke (Big-footed Ant Fly), Mixogaster fattigi Locke, Skevington and Greene (Fattig's Ant Fly), Neoascia guttata Skevington and Moran (Spotted Fen Fly), Orthonevra feei Moran and Skevington (Fee's Mucksucker), Psilota klymkoi Locke, Young and Skevington (Black Haireye) and Trichopsomyia litoralis Vockeroth and Young (Coastal Psyllid-killer). Common names follow the "Field Guide to the Flower Flies of Northeastern North America" (Skevington et al. 2019). [ABSTRACT FROM AUTHOR]

The increased introduction of non-native species to habitats is a characteristic of globalisation. The impact of invading species on communities may be either linearly or non-linearly related to the invaders' abundance in a habitat. However, non-linear relationships with a threshold point at which the community can no longer tolerate the invasive species without loss of ecosystem functions remains poorly studied. We selected 31 wet meadow sites that encompassed the entire coverage spectrum of invasive goldenrods, and surveyed the abundance and diversity of pollinating insects (bees, butterflies and hover flies) and native plants. The species richness of native plants decreased linearly with goldenrod cover, whereas the abundance and species richness of bees and butterflies decreased non-linearly with increasing goldenrod cover. However, no statistically significant changes across goldenrod cover were noted for the abundance and species richness of hover flies. Because of the non-linear response, goldenrod had no visible impact on bees and butterflies until it reached cover in a habitat of about 50% and 30-40%, respectively. Moreover, changes driven by goldenrod in the plant and pollinator communities were related to species loss rather than species replacement. We demonstrated that the impact of goldenrod cover on a habitat is not instantaneous. Habit management aimed at preventing the invasion process and alleviating its impact should take into account that, for the non-linear relationships, the negative impact can appear rapidly after crossing the threshold point. [ABSTRACT FROM AUTHOR]

Abstract Iris species can adopt different pollination strategies to attract their pollinators, generalized shelter-mimicking, specialized deceptive sexual-mimicking or food-rewarding. As attractive stimuli, Iris flowers may use their colours, large-size, symmetry, and volatile organic compounds (VOCs). However, relatively few studies investigated Iris floral olfactory cues in the context of plant-visitor/pollinator interactions. In the present study we combined the identification of the floral volatiles of the nectariferous I. planifolia with insects visiting its flowers to gather data on its biology. Floral volatiles were collected in the natural environment by dynamic headspace and analysed by gas chromatography-mass spectrometry (GC-MS). Insect visitors/pollinators were also recorded. The volatile bouquet was aromatic-dominated with 1,4 dimethoxybenzene as major compound. Among the insects visiting its flowers, bumble and honey bees were the most abundant followed by hover flies. Overall, our results suggest that I. planifolia advertises its food reward by an aromatic dominated volatile composition. Graphical abstract Iris planifolia (Iridaceae) advertises its food reward by an aromatic dominated floral volatile composition. Image Highlights • Aromatic compounds dominate the floral scent bouquet. • 1,4-dimethoxybenzene is the major compound. • The floral scent advertises a food-rewarding species. • Bumble and honey bees are pollinators whereas a syrphid fly is visitor. • Floral olfactory cues probably act in synergy with visual ones to attract bees and flies. [ABSTRACT FROM AUTHOR]

Climate-induced changes in spatial and temporal occurrence of species, as well as species traits such as body size, each have the potential to decouple symbiotic relationships. Past work has focused primarily on direct interactions, particularly those between predators and prey and between plants and pollinators, but studies have rarely demonstrated significant fitness costs to the interacting, coevolving organisms. Here, we demonstrate that changing phenological synchrony in the latter part of the 20th century has different fitness outcomes for the actors within a Batesian mimicry complex, where predators learn to differentiate harmful "model" organisms (stinging Hymenoptera) from harmless "mimics" (hoverflies, Diptera: Syrphidae). We define the mimetic relationships between 2,352 pairs of stinging Hymenoptera and their Syrphidae mimics based on a large-scale citizen science project and demonstrate that there is no relationship between the phenological shifts of models and their mimics. Using computer game-based experiments, we confirm that the fitness of models, mimics, and predators differs among phenological scenarios, creating a phenologically antagonistic system. Finally, we show that climate change is increasing the proportion of mimetic interactions in which models occur first and reducing mimic-first and random patterns of occurrence, potentially leading to complex fitness costs and benefits across all three actors. Our results provide strong evidence for an overlooked example of fitness consequences from changing phenological synchrony. [ABSTRACT FROM AUTHOR]

A wide variety of insect species provide pollination services in natural and agricultural ecosystems, but in order to quantify their contribution it is necessary to evaluate their effectiveness. An important component of this is to determine their ability to transfer pollen to stigmas which typically requires observers to wait for insects to visit focal flowers (static approach); a time-consuming process not amenable to obtaining measures for pollinating species of low local abundance. An alternative method (active approach) is to detach test flowers and present them to the targeted flower visitor. This offers a number of advantages ( e.g. increased speed and flexibility), but may alter insect behaviour. We compared pollen deposition within flowering onion crops using three bee (Apoidea) and three fly (Diptera) species. The two approaches resulted in similar numbers of pollen grains being deposited onto stigmas for each insect species, thereby supporting the validity of the active as an alternative to the static approach in our test crop. The ability to rapidly assess stigmatic pollen deposition of a broad range of insects using the active approach can greatly assist assessments of pollinator contribution within plant pollinator assemblages. [ABSTRACT FROM AUTHOR]

The continued expansion of pollinator-dependent crops increases our reliance on insect pollinators, with wild pollinators providing a considerable proportion of pollination services depending on the crop and landscape context. To ensure pollination services delivered by wild pollinators, it is suggested to conserve semi-natural habitat (SNH) in agricultural landscapes. However, quantitative thresholds of the required amount of SNH to inform policy and farmers are lacking. This study assessed how non-linear models can predict the relationship between wild pollinator visitation and SNH near sweet cherry orchards in Belgium. In addition, I determined a threshold of the required amount of SNH to support pollinator visitation. The relationship between total wild pollinator visitation, bumble bee visitation, solitary bee visitation and wild pollinator richness was best predicted by a non-linear relationship with the proportion of SNH within 250 m around the fields. This study provides empirical evidence on the benefit of using non-linear models to increase our understanding between landscape structure and pollinator visitation. 15% of SNH is the estimated threshold beyond which pollinator visitation did not increase any further. Increasing the amount of SNH to 15%, if it is below this threshold, is recommended to enhance crop pollination in this specific system and region. Conservation of SNH at higher levels than 15% should be maintained for biodiversity conservation and ecosystem functioning. • The relation between landscape and pollinators was studied with non-linear models. • Pollinator visitation increases non-linear with the amount of semi-natural habitat. • 15 % semi-natural habitat was identified as minimum to ensure pollinator visitation. [ABSTRACT FROM AUTHOR]

Background: The present paper describes a sampling-event dataset on species belonging to two families of Diptera (Syrphidae and Asilidae) collected between 2012 and 2019 in two Italian beech forests located in the central Apennines. The reference dataset consists of an annotated checklist and has been published on Zenodo. Syrphidae and Asilidae are two widespread and key ecological groups, including predator, pollinator and saproxylic species. Despite their pivotal role in both natural and man-made ecosystems, these families are still poorly known in terms of local distribution and open-access sampling-event data are rare in Italy., New Information: This open-access dataset includes 2,295 specimens for a total of 21 Asilidae and 65 Syrphidae species. Information about the collection (e.g. place, date, methods applied, collector) and the identification (e.g. species name, author, taxon ID) of the species is provided. Given the current biodiversity crisis, the publication of checklists, sampling-event data and datasets on insect communities in open-access repositories is highly recommended, as it represents the opportunity to share biodiversity information amongst different stakeholders. Moreover, such data are also a valuable source of information for nature reserve managers responsible for monitoring the conservation status of protected and endangered species and habitats and for evaluating the effects of conservation actions over time., (Alice Lenzi, Daniele Birtele, Silvia Gisondi, Mario Romano, Bruno Petriccione, Pierfilippo Cerretti, Alessandro Campanaro.)

The specimens of the tribe Syrphini, deposited at the Hayk Mirzayans Insect Museum, were examined and 30 species identified, of which one genus and three species are newly recorded from Iran and marked by an asterisk (*). Keys to the genera and species, as well as their distribution in Iran, are provided. The species are as follows:Dasysyrphus albostriatus (Fallen), D. eggeri (Schiner), Dideoides annandalei (Brunetti), Epistrophe eligans (Harris)*, E. euchroma (Kowarz), Episyrphus balteatus (De Geer), Ischiodon aegyptius (Wiedemann), I. scutellaris (Fabricius), Melangyna* cincta (Fallen)*, Meliscaeva cinctella (Zetterstedt), M. auricollis (Meigen), Eupeodes corollae (Fabricius), E. latifasciatus (Macquart), E. lunigar (Meigen), E. nuba (Wiedemann), Scaeva albomaculata (Macquart), S. dignota (Rondani), S. latimaculata (Brunetti), S. pyrastri (Linnaeus), S. rossica Kuznetsov, S. selenitica (Meigen), Sphaerophoria bengalensis Macquart, Sph. rueppelli (Wiedemann), Sph. scripta (Linnaeus), Syrphus ribesii (Linnaeus), S. torvus Osten Sacken, S. vitripennis Meigen, Xanthogramma laetum (Fabricius)*, X. maculipenne Mik and X. pedissequum (Harris).

Knowledge of floral biology is essenti.il to crop improvement. Ten genotypes of fluted pumpkin {Telfairia occidentalis) were observed for floral morphology, phenology and insect visitation for two consecutive years. Functional dioecy of fluted pumpkin was confirmed, whereas none of the studied genotypes was monoecious. Floral structures differed significantly among the genotypes. Both male and female flowers were symmetrical, pentasepalous, fimbriate and non-bright pentapetalous, but male flowers were more numerous. Male inflorescences emerged from 11 to 14 weeks after planting and the female flower buds appeared about 4 weeks later. The flowering period of the male flowers was longer than that of female flowers and both gender flowering periods coincided for a specific interval. It took between 11 to 14 days from bud initiation to anthesis and flowering ceased when there were occurrences of successful fruits set. In both gender flowers petals started unfurling at around 6.00 pm and full bloom was achieved by dawn, while petal shrivelled at sun set (between 6.30 pm to 7.30 pm). The anthers dehisced at anthesis of the male flowers; the pollen grains were whitish and sticky. Only the male flowers have nectar and pollen and this may explain infrequent female flowers visitation. Hover flies {Cheilosia species) were the major floral visitors observed. [ABSTRACT FROM AUTHOR]

Laboratory experiments were conducted to determine the functional and numerical responses of the aphidophagous hover fly Episyrphus balteatus DeGeer (Diptera: Syrphidae) to different densities of 4th instar black bean aphids, Aphis fabae Scopoli (Homoptera: Aphididae), on broad bean, Vicia faba L. (Fabaceae). Two different-sized larvae of predators were tested in different densities of similar-sized prey to determine whether functional response parameters depended on the body sizes of predator and prey. In numerical response experiments, gravid E. balteatus females were exposed individually to different densities of 4th instars of A. fabae on cut sections of the broad bean plant, V. faba L. Logistic regression suggested a type II functional response for both larval sizes of E. balteatus. The searching efficiency (a) of the larger larvae was higher than that of the smaller ones. Prey consumption was higher, and handling time (Th) was lower for larger larvae than smaller ones. The theoretical maximum number of A. fabae nymphs eaten by the different-sized larvae was 125 and 269 nymphs per day. Larger E. balteatus larvae are more efficient predators for aphid management strategies. The reproductive numerical response, in terms of the number of eggs laid, increased curvilinearly with increasing prey density, but the proportion of eggs laid (egg number/prey density) decreased as the initial density of prey increased. [ABSTRACT FROM AUTHOR]

Pollinating insects are globally declining, with one of the main causes being the loss of flowers. With the value of countryside reducing, urban areas, particularly gardens, are increasingly recognized as of benefit to wildlife, including flower-visiting insects., Many gardeners specifically select plant varieties attractive to wildlife. Given the wide public interest, many lists of recommended varieties have been produced by both amateurs and professional organizations, but appear not to be well grounded in empirical data. These lists, however, are not without merit and are an obvious starting point. There is clearly a need to put the process onto a firmer footing based more on data and less on opinion and general experience., We collected data over two summers by counting flower-visiting insects as they foraged on 32 popular summer-flowering garden plant varieties in a specially planted experimental garden, with two smaller additional gardens set up in year two to check the generality of the results. With many thousands of plant varieties available to gardeners in the United Kingdom, and other countries or regions, it would have been an impossible task to make a comprehensive survey resulting in a complete and authoritative list., Our results are valuable and encouraging. Garden flowers attractive to the human eye vary enormously, approximately 100-fold, in their attractiveness to insects. Insects, especially bees and hover flies, can be attracted in large numbers with clear differences in the distribution of types attracted by different varieties., Our results clearly show that there is a great scope for making gardens and parks more bee- and insect-friendly by plant selection. Horticulturally modified plant varieties created by plant breeding, including hybrids, are not necessarily less attractive to insects and in some cases are more attractive than their wild-type counterparts. Importantly, all the plants we compared were considered highly attractive to humans, given that they are widely sold as ornamental garden plants., Helping insect pollinators in gardens does not involve extra cost or gardening effort, or loss of aesthetic attractiveness. Furthermore, the methods of quantifying insect-friendliness of plant varieties trialled in this study are relatively simple and can form the basis of further research, including 'citizen science'. [ABSTRACT FROM AUTHOR]

The evolution of mimicry, and particularly the persistence of undefended Batesian mimetic forms that are imperfect copies of their defended models, remains a central question in evolutionary biology. Previous work has demonstrated that variation in mimetic fidelity in artificial prey can alter survival. However, no studies have validated the assumption that detailed laboratory-based measurements of mimetic fidelity are actually reflected in survival in natural field experiments. Here, we demonstrate that, in line with previous studies, the mimetic similarity of 77 hover fly (Diptera: Syrphidae) species to the common wasp Vespula alascensis is strongly related to the number of abdominal stripes exhibited by the flies. We then produce three artificial pastry baits: (1) a 'model' which is chemically defended and has two stripes, (2) a one-stripe mimic, and (3) an unstriped mimic. Based on the ratings study, we predicted that the one-stripe mimic would exhibit survival intermediate between the unstriped mimic and the model. Baits were deployed in experiments each involving 81 baits (27 of each kind), at 3 sites, with experiments replicated 10 times at each site for a total deployment of 2,430 baits. Proportional hazards models show that both one-striped and model baits survived equally well and significantly better than the unstriped baits, suggesting categorical prey identification rather than the use of stripe number as a continuous trait, as was suggested by the laboratory study. These findings suggest that, while humans and avian predators can distinguish mimics from models in the laboratory using a range of traits, behaviour in the field may not reflect this ability. This absence of a link between continuous measures of mimetic fidelity and prey selection may contribute to the maintenance of imperfect mimicry, but more studies using near-natural experimental paradigms are needed to investigate the phenomenon further. [ABSTRACT FROM AUTHOR]