Species Of Sawflies Research Articles

New woodlands are boosting the Shetland Islands' sawfly diversity (Hymenoptera: Symphyta: Tenthredinidae)

Five species of sawfly are recorded for the first time from the Shetland Islands, four of which were found in a planted woodland first established in 1996. All five use shrubs and trees as larval hosts: two are attached to Alnus Mill., and three exclusively or mainly to Salix L. Whereas the Alnus -feeders have almost certainly been introduced to Shetland, the history of the Salix -feeders in the archipelago is unclear. Pristiphora sermola Liston, 1993, is faunistically noteworthy, having previously been recorded in the British Isles from only two localities in the Scottish mainland. With these additions, the known sawfly fauna of Shetland now comprises 13 established species, with one more needing confirmation.

Furostanol Saponins and Ecdysteroids from Plants of the Genus Helleborus as Phagostimulants and Predator Deterrents for Larvae of Two Monophadnus Sawfly Species.

Sawfly species of the genus Monophadnus are specialised on Ranunculaceae plants from which the larvae can sequester furostanol saponins into the haemolymph, mainly (25R)-26-[(α-L-rhamnopyranosyl)oxy]-22α-methoxyfurost-5-en-3β-yl-O-β-D-glucopyranosyl-(1→3)-O-[6-acetyl-β-D-glucopyranosyl-(1→3)]-O-β-D-glucopyranoside (compound 1). In this work, TLC, GC-MS, and HPLC-DAD-ESI/MS analyses together with feeding, repeated simulated attacks, and ant deterrence bioassays were conducted to extend the chemoecological knowledge about two sawfly species specialised on H. foetidus L. (Monophadnus species A) and H. viridis L. (Monophadnus species B). Larvae of Monophadnus species B were mostly feeding on the squares treated with the n-butanol fraction from H. foetidus, compound 1 being its primary non-nutritional stimulant. In contrast, all H. viridis fractions stimulated feeding, with n-hexane marginally more active. β-sitosterol within n-hexane was determined as the nutritional stimulant. Quantitative analyses demonstrated that leaves of H. viridis but not H. foetidus contain the ecdysteroids 20-hydroxyecdysone and polypodine B. Moreover, the haemolymph of Monophadnus species B larvae reared on H. viridis contained the glycosides of polypodine B and 20-hydroxyecdysone at a concentration of 2.5 to 6.8 µmol/g fresh weight of haemolymph. This concentration is several thousand times higher than the concentration range of the aglycones in their host plant (3.63 × 10-4 to 2.23 × 10-4 µmol total ecdysteroids/g fresh weight of leaves), suggesting bioaccumulation. The larvae of both species fed on H. foetidus do not show any traces of ecdysteroids in their haemolymph, indicating a facultative role of these compounds in their defence as well as their inability to endogenously synthesise these compounds. The haemolymph containing ecdysteroids was a significant feeding deterrent against Myrmica rubra L. ant workers (one of their natural predators) at 0.8 mg/mL. The larvae kept effective deterrent levels of glycosylated ecdysteroids (≅175 mM) between simulated attacks on days 1 and 2, but the levels clearly decreased on day 3 (≅75 mM). Most larvae (89%) survived a first attack but only 23% a consecutive second one. As a conclusion, we report for the first time that two Monophadnus species feeding on H. viridis sequester phytoecdysteroids into the larval haemolymph in the form of glycosides. In addition, compound 1 possesses defensive and phagostimulant activities, and we present evidence for a combined effect of furostanol saponins and ecdysteroids as repellents against ants.

A new species of Acantholyda (Hymenoptera: Pamphiliidae) from Lebanon, associated with Cedrus libani (Pinaceae)

Acantholyda nemeri sp. nov. (Hymenoptera: Pamphiliidae) is described from adults of both sexes from Lebanon. Its host plant is probably Cedrus libani, the cedar of Lebanon (Pinaceae). The new species shows a combination of adult characters that makes placing it in one of the two widely-recognised subgenera of Acantholyda problematic. Acantholyda nemeri is only the fourth sawfly species associated with Cedrus as a larval host and, together with Cephalcia tannourinensis Chevin, 2002 (Pamphiliidae), the second from C. libani. A key to adults of Acantholyda Costa, 1894 species of the Western Palaearctic is provided.

The mitochondrial genome and life history of Tomostethus sinofraxini (Hymenoptera: Tenthredinidae), an emerging pest of Fraxinus chinensis.

Tomostethus sinofraxini Wang & Wei (a new name is proposed for Tomostethus fraxini Niu & Wei, 2022: Tomostethus sinofraxini Wang & Wei, nom. nov.), an emerging sawfly pest of the Chinese ash, Fraxinus chinensis, is now endemic to Beijing, Tianjin, Hebei, and Shandong provinces. Given the severity of its infestation and the speed of its range expansion, we studied the phylogenetic relationship of T. sinofraxini with other sawfly species and its life history to be better informed for the management strategies. The nearly complete T. sinofraxini mitogenome is 16,169 bp in length and encodes 2 ribosomal RNAs (rrnL and rrnS), 22 transfer RNAs (tRNAs), and 13 protein-coding genes. The nucleotide composition is biased toward adenine and thymine (A + T = 81.7%). In comparison to the architecture of the ancestral insect mitogenome, 2 transposition events occur on the IQM tRNA cluster, rearranging it from IQM to MQI. Our phylogenetic analysis suggests that T. sinofraxini belongs to a group composed of paraphyletic subfamilies Blennocampinae and Heterarthrinae. In addition, to document its life history, we observed T. sinofraxini development at 2 geographical locations in Beijing, China, with different altitudes. At Jiulong Mountain, with a higher altitude and a lower average temperature, the developmental time of egg, larval, and adult stages was 19%-31% longer than that observed at the Chinese Academy of Forestry. A basic understanding of biological traits and molecular signatures is the critical first step to develop an integrated pest management framework for this emerging pest of the Chinese ash.

Chromosomes of the genus Arge Schrank, 1802 (Hymenoptera, Argidae): new data and review.

Results of the chromosome study of 12 sawfly species of the genus Arge Schrank, 1802 are reviewed, including new data on the karyotypes of A.ciliaris (Linnaeus, 1767) and A.enodis (Linnaeus, 1767) with n = 10. Moreover, the same chromosome number, n = 10, is found in A.ustulata (Linnaeus, 1758), for which n = 8 was previously reported. In addition, n = 8 is confirmed in A.gracilicornis (Klug, 1814). The results of the morphometric analysis of chromosome sets of these four species are given. In the genus Arge, haploid chromosome numbers of n = 8, 10, 11 and 13 were found. Among these sawflies, n = 8 appeared to be the most frequent chromosome number, followed by n = 10. The known data of the chromosome study of these insects are summarized and discussed in the light of phylogeny and taxonomy of the genus Arge.

NEW REMARKABLE RECORDS OF SAWFLIES FROM SICILY (HYMENOPTERA CIMBICIDAE, SIRICIDAE)

Two remarkable species of sawflies are newly recorded for Sicily: Cimbex fagi (Zaddach, 1863) (Cimbicidae) from Nebrodi and Madonie Mountains, and Xeris pallicoxae Goulet, 2015 from Etna Volcano (Siricidae), whereas Urocerus sah (Mocsary, 1881), only recently recorded from western Sicily as U. augur, is newly recorded from eastern Sicily (Etna Volcano). Information on the occurrence of these three sawflies is provided, along with brief ecological data. With these new records the number of species of sawflies known for Sicily rises to 150, belonging to ten families, including 7 Cimbicidae and 4 Siricidae. Key Words: sawflies, new records, Cimbicidae, Siricidae, forestal ecology.

Detection of a mass breeding site of the elm sawfly-zigzag <i>Aproceros leucopoda</i> Takeuchi, 1939 (Hymenoptera: Argidae) in Voronezh

During entomological monitoring, three species of sawflies were observed in the plantings of small-leaved elm Ulmus pumila Linnaeus (1753), rough U. glabra Hudson (1762) and smooth U. laevis Pallas (1784) in Voronezh. Slight overeating by the elm sawfly Cladius ulmi (Linnaeus, 1758) (Tenthredinidae) was found throughout the study area on three species of elms. Mines of the elm mining sawfly Fenusa ulmi Sundevall, 1847 (Tenthredinidae) were found only on the rough elm in the Northern district of the city. Isolated damage to the leaves of U. pumila by the zigzag sawfly Aproceros leucopoda Takeuchi, 1939 (Argidae) was noted in all districts of the city, U. glabra – only in two points of the Northern district. In early July 2023, a hearth with a high number of zigzag sawflies on U. pumila was discovered in the park of the Sovetsky district, in which 90% defoliation on U. pumila was recorded by early August. The flight of the imago of A. leucopoda on the territory of three parks and squares of the Sovetsky district was marked in the first decade of July. The female sawfly was caught on a city bus with the starting point of the route near the found hearth with a high number of sawflies, which confirms the transfer of the imago of the zigzag sawfly within the city by public transport.

Investigating the abundance and diversity of sawflies (Hymenoptera, Symphyta) within commercial Sitka spruce plantation forests in mid‐Wales

Abstract Sitka spruce is a widely planted and economically important tree species in the United Kingdom; hence, identifying any future biotic or abiotic threats to its productivity is important. Defoliating insects are widely considered to be major forest disturbance agents, and these can include the sawflies (Symphyta), which are well known to reach high population densities that can cause significant outbreak events, leading to tree mortality or impacts on growth. The aim of the current study was to investigate the abundance and diversity of sawflies within stands of Sitka spruce over an elevation range and to evaluate whether there were any potentially important species present. Experimental plots were established in two commercial forest plantations in mid‐Wales, and the adult sawfly community was assessed over a 3‐year period using yellow pan traps. Sixty species of sawfly were caught over the 3‐year period, which accounted for >11% of all known British sawfly species. Results indicated that there were generally greater abundance and diversity of sawflies at lower elevational plots, where temperatures were higher. The most abundant sawfly species captured in the study was the notable defoliator species, the mountain spruce sawfly (Epicenematus montanus), which was found in particularly high numbers in the low‐elevation plot in Hafren forest. A further seven spruce‐associated sawfly species were also caught across the experimental plots. The study highlighted the presence of a number of notable spruce‐associated sawfly species (E. montanus and Pristiphora spp.), some of which have caused significant defoliation of spruce (Picea) species in Europe. The generally higher abundance of these sawflies at lower elevations indicated that Sitka spruce may potentially become more vulnerable to defoliation events caused by sawfly outbreaks in the future, especially when considering current projected climate change predictions.

Spectral radius is a better metric than weighted NODF to detect network nestedness: Linking species coexistence to network structure using a plant – larval sawfly bipartite

1.Network nestedness describes an interaction pattern, wherein specialist species interact with a subset of partner species. Antagonistic networks are predicted to not be nested, because nestedness indicates a high intensity of interspecific competition, which compromises species coexistence. However, network nestedness is commonly observed in antagonistic networks, and the discrepancy between prediction and observation has not been fully resolved.2.One of underlying factors explaining this discrepancy is the imperfection of metrics to detect network nestedness. However, studies comparing network metrics often fail to resolve which metric works best, presumably because they lack specific criteria.3.We compared the results of the most commonly used metrics (weighted NODF) and a later proposed metric (spectral radius) to measure the nestedness of a quantitative plant - larval sawfly bipartite (including 8 sawfly species and 66 plant species, identified by gut DNA metabacoding of larvae). We also determined whether the sawfly species can coexist in terms of their dietary differences. Because nested structure is not likely to be compatible with species coexistence, we assumed that the metric identifying a non-nested structure is superior to the other.4.The two metrics led to contrasting nestedness levels. Both observational and preference networks were found to be nested using weighted NODF, but was not nested using the spectral radius approach.5.The dietary differences were significant among each sawfly species pair for both observational and preference networks, indicating low interspecific competitiveness and a high potential for species coexistence.6.These results indicate that the spectral radius metric is superior to weighted NODF to detecting network nestedness and should be used in future network studies.

Taxonomy, distribution and host plants of some southern European and North African Sawflies (Hymenoptera, Symphyta)

New taxonomic, biological and faunistic data are presented for some species of sawflies occurring in southern Europe and North Africa. Pamphilius mediterraneussp. nov. is described from Italy (Sicily). It belongs to the alternans sub-group of the alternans species group. Pristiphora omalossp. nov. is described from Greece (Crete). It belongs to the depressa species group. New junior synonyms are Calameuta tazzekae Lacourt, 1991 of Calameuta gaullei (Konow, 1896), and Emphytus leucostomus Costa, 1890 of Allantus cingulatus (Scopoli, 1763). Periclista rufiventris Zombori, 1979 is moved from the subgenus Periclista to the subgenus Neocharactus. Ametastegia (Protemphytus) persica Khayrandish, Talebi & Blank, 2015 is recorded for the first time in Europe, from Italy (Sicily), and a key to West Palaearctic Protemphytus species provided. Allantus enslini (Forsius, 1918) is more widespread in southern Europe than previously recorded. An identification key distinguishes it from its closer West Palaearctic relatives. New hostplant records are for Halidamia affinis (Fallén, 1807) (Rubia peregrina), Janus compressus (Fabricius, 1793) (Sorbus torminalis), and Macrophya albicincta (Schrank, 1776) (Centranthus ruber). New distribution records are given for a few other species.

Cypress terpenes in sawfly larva of Susana cupressi (Hymenoptera: Symphyta: Tenthredinoidea).

Several sawfly species (Hymenoptera: Symphyta) possess larval stages with oesophageal diverticula in which plant compounds are sequestered and used for defence against predators. These organs are present in the larvae of Susana (Tenthredinidae) but remain poorly studied. Here, the aim was to analyse the diverticula extract of Susana cupressi by gas chromatography-mass spectrometry to better understand the ecology of this species. The foliage of the hostplant (Cupressus sempervirens), as well as the larval foregut, midgut, and haemolymph were also analysed. Complementary data were gathered by morphological observations, bioassays using ants, and genetic analyses to identify the studied Susana species. Altogether, 48 terpenes were identified, 30 being sesquiterpenes. The terpenes were generally detected in the foliage, but also in the diverticula, foregut, and midgut, whereas none of them in the haemolymph. The main compounds were alpha-cedrene, alpha-fenchene, alpha-pinene, alpha-terpinyl acetate, beta-myrcene, beta-pinene, cedrol, delta 3-carene, epi-bicyclosesquiphellandrene, germacrene D, limonene, sabinene, and terpinolene. The chemical profiles of these 13 compounds were significantly correlated between foliage-diverticula, diverticula-foregut and foregut-midgut, but not correlated for the three remaining possible comparisons. Alpha-pinene decreased and germacrene D increased from the foliage to the diverticula, which may reflect a specific sequestration of the latter terpene and its known deleterious effects on insects. We conclude that larvae of S. cupressi, similarly to those of diprionids, are well defended against predatory attacks by sequestering and regurgitating hostplant terpenes, including germacrene D.

Les Hyménoptères Symphytes de Corse, bilan des connaissances et nouveaux signalements (Hymenoptera, Symphyta)

Hymenoptera Symphyta of Corsica: knowledge review and new records. Studying collected material of some field trips during the Our Planet Reviewed in Corsica 2019-2021 scientific expeditions and coming from a survey with a Malaise trap by the Office de l’Environnement de Corse, many species were recorded, of which 14 of great interest. Pseudoryssus henschii is a new country record for France and the following 13 additional species are reported for the first time in Corsica: Janus compressus, Arge berberidis, Brachythops flavens, Aneugmenus coronatus Athalia liberta, Allantus togatus, Emphytus laticinctus, Monostegia abdominalis, Priophorus brullei, Priophorus compressicornis, Cytisogaster genistae, Macrophya annulata and Tenthredo temula. Currently, 94 species of sawflies (Hymenoptera, Symphyta) are known in Corsica.

Body size as a magic trait in two plant-feeding insect species.

When gene flow accompanies speciation, recombination can decouple divergently selected loci and loci conferring reproductive isolation. This barrier to sympatric divergence disappears when assortative mating and disruptive selection involve the same "magic" trait. Although magic traits could be widespread, the relative importance of different types of magic traits to speciation remains unclear. Because body size frequently contributes to host adaptation and assortative mating in plant-feeding insects, we evaluated several magic trait predictions for this trait in a pair of sympatric Neodiprion sawfly species adapted to different pine hosts. A large morphological dataset revealed that sawfly adults from populations and species that use thicker-needled pines are consistently larger than those that use thinner-needled pines. Fitness data from recombinant backcross females revealed that egg size is under divergent selection between the preferred pines. Lastly, mating assays revealed strong size-assortative mating within and between species in three different crosses, with the strongest prezygotic isolation between populations that have the greatest interspecific size differences. Together, our data support body size as a magic trait in pine sawflies and possibly many other plant-feeding insects. Our work also demonstrates how intraspecific variation in morphology and ecology can cause geographic variation in the strength of prezygotic isolation.

Sawflies (Hymenoptera: Symphyta) from North-Western Georgia (Sakartvelo)

In total, 388 specimens belonging to 61 species of sawflies were collected in North-Western Georgia in 2020. Among the collected species, 29 are new country records.

Feeding behaviour in Australian gregarious Lophyrotoma sawflies (Hymenoptera: Pergidae)

AbstractDetails of feeding behaviour of Australian sawfly species on eucalypt hosts are not well known. In this study, we report new findings on two pergid sawflies, Lophyrotoma interrupta and an unidentified species of Lophyrotoma, after observing larvae feed. We confirmed both daily and nightly feeding regimes, with L. interrupta and Lophyrotoma sp. engaged in feeding‐related activities 92.2% and 67.0% of the time, respectively. A colony sometimes splits into subcolonies as a leaf depletes; individuals leave singly and explore surrounding leaves before joining the rest of the colony feeding on the new leaf. As a specific feeding behaviour, the larvae of both species cut midveins on surrounding leaves in one of several ways before and during feeding. Larvae used pre‐processed cut leaves at a ratio ranging from 0.64 to 0.88 of the whole leaves eaten. Of the leaves cut prior to feeding, approximately half were not consumed, whereas the remaining were consumed 2 days after cutting (median time). We observed a decreasing trend of further cuttings when the proportion of damaged leaves in the surrounding area was increased. Feeding of Lophyrotoma sp. followed a clear pattern: Usually, the last individual remaining on the leaf severed the leaf petiole as it left. This petiole snipping occurred in over half the leaves that larvae had used; however, this behaviour was not observed in L. interrupta.

Nueva especie de mosca sierra del género ZadiprionRohwer (Hymenoptera: Diprionidae) atacando Pinus cembroides (Zucc.) en Tamaulipas, México

Introduction:Zadiprion Rohwer is a genus of sawflies including seven species that cause defoliations in coniferous forests. Objective: To determine the species of Zadiprion sawflies infesting Pinus cembroides (Zucc.) in Miquihuana, Tamaulipas. Materials and methods: Biological material was collected from sawfly larvae. Part of the material was preserved in 70 % alcohol for morphological description, another in 96 % anhydrous alcohol for molecular identification and another portion was placed in a Binder 720 KBW E5.1 to complete the biological cycle and obtain adults. The ovipositor of the female and phenology during five years were described. Results and discussion: The sawfly larva has an orange-brown head with a small circular eyestalk, a longitudinal brown spot on the dorsum, two white lines on the sides and a dark subdorsal stripe. The female is light yellow with dark sutures on the thorax. The lancet of the ovipositor has nine rings; the first is inverted “U” shaped. Males are mainly black with yellowish legs and a yellowish-brown spot in the postocellar area; there is no yellowish-brown pronotum or tegula and the harpes are rounded and pale at the apex. The population is different from Z. rohweri (Middleton) and Z. jeffreyi (Smith), reported in GenBank; however, they are related. Conclusions: The sawf ly under study is a new species and was recorded as Zadiprion borjaisp. nov. (GenBank: ON181557).

Sawfly Fauna (Hymenoptera: Symphyta) in the Mordovia State Nature Reserve (Central Russia)

Protected areas are biodiversity hotspots of the world. Knowledge of their overall biodiversity is essential for nature conservation. Sawflies are an integral part of terrestrial ecosystems; being phytophages, they play a significant role in the processing of primary production. The aim of the research was to study the biodiversity of sawflies in the Mordovian Reserve. The research was carried out in 2008, 2009 and 2012-2019 on the territory of the Mordovia State Nature Reserve (Republic of Mordovia, Central part of European Russia). The article provides information on records of 169 species of sawflies of 9 families in the Mordovia State Nature Reserve. The annotated list includes 103 new species for the reserve, of which 1 species (Dineura parcivalvis) is listed for the European part of Russia for the first time, and 3 species are specified for the first time for the Central part of European Russia (Arge beckeri, Rhogogaster genistae, Tenthredo amurica).

In memory of Bruno Peter: fresh insights on the Swiss sawfly fauna (Hymenoptera, Symphyta)

Bruno Peter-Sager (1943–2018) was a Swiss entomologist who collected and studied sawflies, and published on these under the name Bruno Peter. His large collection is deposited in the Senckenberg Deutsches Entomologisches Institut, Müncheberg, Germany. Following a short biography, we present commentaries on noteworthy specimens from Switzerland and some general and specific characteristics of the Swiss sawfly fauna, based on his collection and database. Twenty sawfly species are recorded for the first time in Switzerland: Aprosthema bifurca, Arge fuscipennis, Cladardis hartigi, Dolerus altivolus, D. brevicornis, D. zhelochovtsevi, Empria fletcheri, Euura amentorum, E. cyrnea, E. longiserra, E. scotonota, Nescianeura noblecourti, Pristiphora depressa, P. luteipes, P. nigricans, Rhogogaster polaris, Taxonus alboscutellatus, Tenthredo semicolon, Tenthredopsis tischbeinii and Calameuta idolon. Three species are removed from the national list: Cladardis bordonii, Taxonus sticticus and Tomostethus melanopygius. Records from Switzerland of seven little-known or rarely recorded species are also discussed. Data for most specimens collected by B. Peter include altitude, enabling presentation of results of some analyses of species richness related to altitude, as well as examples of patterns of altitudinal abundance for selected species.

Response of specialist and generalist predators to nonprogressive annual fluctuations in herbivorous insect populations

To control sawfly populations that cause a forest management problem due to feeding damage, it is necessary to understand the mechanism of eruptive outbreak in erratic intervals by clarifying the responses of natural enemies to the host population fluctuations. In this study, we investigated annual beech sawfly population fluctuations and its predator, ichneumonid parasitoid wasps (as specialists) and predatory soldier beetles (as generalists). In addition, yearly responses of predators to the host emerging patterns were examined using structural equation modeling. The results revealed that ichneumonid wasps showed a non-delayed synchronous response to erratic fluctuation of the host population, resulting in the maintenance of a constant parasitism ratio. In contrast, soldier beetle population, which tends to moderately fluctuate while maintaining a specific density, showed a low-intensity delayed response without significance in the model. These predator populations without strong delayed density-dependent response are quite unlikely to highly densify causing mass mortality to the host population in the both the current and following years of outbreak. In places where eruptive outbreaks of sawfly species repeatedly occur in erratic intervals, sawfly populations are possibly maintained in high density due to the low mortality ratio caused by predators.

New genus and species of syspastoxyelid sawflies (Insecta, Hymenoptera) from the mid-Cretaceous Kachin amber with a review of the family Syspastoxyelidae

Burmoxyela lii gen. et sp. nov. is described and illustrated based on a male collected from mid-Cretaceous Kachin (Burmese) amber. Pinguixyela gen. nov. is described for Syspastoxyela pinguis Wang, Shih, Ren & Gao, 2019, and Syspastoxyelasimpla Wang, Shih, Ren & Gao, 2019 is transferred to the genus Striaexyela Zheng et al., 2019 as Striaexyela simpla (Wang, Shih, Ren & Gao, 2019), comb. nov., both from Kachin amber. This results in 5 genera and 6 species comprising the family thus far. A key to genera and species of Syspastoxyelidae is provided. The family is consideded as the most basal branch of Hymenoptera sister to Xyelidae. Biologically Syspastoxyelidae are hypothesized to develop within male cones of conifer trees and to feed on pollen grains both as adult and immature. Our discovery supports the hypothesis that the mid-Cretaceous Kachin biota was highly endemic.