Phylogenomics and biogeography of sawflies and woodwasps (Hymenoptera, Symphyta).

Phylogenomic approaches have recently helped elucidate various insect relationships, but large-scale comprehensive analyses on relationships within sawflies and woodwasps are still lacking. Here, we infer the relationships and long-term biogeographic history of these hymenopteran groups using a large dataset of 354 UCE loci collected from 385 species that represent all major lineages. Early Hymenoptera started diversifying during the Early Triassic âˆ¼249 Ma and spread all over the ancient supercontinent Pangaea. We recovered Xyeloidea as a monophyletic sister group to other Hymenoptera and Pamphilioidea as sister to Unicalcarida. Within the diverse family Tenthredinidae, our taxonomically and geographically expanded taxon sampling highlights the non-monophyly of several traditionally defined subfamilies. In addition, the recent removal of Athalia and related genera from the Tenthredinidae into the separate family Athaliidae is supported. The deep historical biogeography of the group is characterised by independent dispersals and re-colonisations between the northern (Laurasia) and southern (Gondwana) palaeocontinents. The breakup of these landmasses led to ancient vicariance in several Gondwanan lineages, while interchange across the Northern Hemisphere has continued until the Recent. The little-studied African sawfly fauna is likewise a diverse mixture of groups with varying routes of colonization. Our results reveal interesting parallels in the evolution and biogeography of early hymenopterans and other ancient insect groups.

Trait-mediated responses of caterpillar communities to spongy moth outbreaks and subsequent tebufenozide treatments.

Outbreaks of the spongy moth Lymantria dispar can have devastating impacts on forest resources and ecosystems. Lepidoptera-specific insecticides, such as Bacillus thuringiensis var. kurstaki (BTK) and tebufenozide, are often deployed to prevent heavy defoliation of the forest canopy. While it has been suggested that using BTK poses less risk to non-target Lepidoptera than leaving an outbreak untreated, in situ testing of this assumption has been impeded by methodological challenges. The trade-offs between insecticide use and outbreaks have yet to be addressed for tebufenozide, which is believed to have stronger side effects than BTK. We investigated the short-term trade-offs between tebufenozide treatments and no-action strategies for the non-target herbivore community in forest canopies. Over 3 years, Lepidoptera and Symphyta larvae were sampled by canopy fogging in 48 oak stands in southeast Germany during and after a spongy moth outbreak. Half of the sites were treated with tebufenozide and changes in canopy cover were monitored. We contrasted the impacts of tebufenozide and defoliator outbreaks on the abundance, diversity, and functional structure of chewing herbivore communities. Tebufenozide treatments strongly reduced Lepidoptera up to 6 weeks after spraying. Populations gradually converged back to control levels after 2 years. Shelter-building species dominated caterpillar assemblages in treated plots in the post-spray weeks, while flight-dimorphic species were slow to recover and remained underrepresented in treated stands 2 years post-treatment. Spongy moth outbreaks had minor effects on leaf chewer communities. Summer Lepidoptera decreased only when severe defoliation occurred, whereas Symphyta declined 1 year after defoliation. Polyphagous species with only partial host plant overlap with the spongy moth were absent from heavily defoliated sites, suggesting greater sensitivity of generalists to defoliation-induced plant responses. These results demonstrate that both tebufenozide treatments and spongy moth outbreaks alter canopy herbivore communities. Tebufenozide had a stronger and longer lasting impact, but it was restricted to Lepidoptera, whereas the outbreak affected both Lepidoptera and Symphyta. These results are tied to the fact that only half of the outbreak sites experienced severe defoliation. This highlights the limited accuracy of current defoliation forecast methods, which are used as the basis for the decision to spray insecticides.

Presence of the canonical TTAGG insect telomeric repeat in the Tenthredinidae (Symphyta) suggests its ancestral nature in the order Hymenoptera.

Telomeric repeats in two members of the sawfly family Tenthredinidae (Hymenoptera), namely, Tenthredo omissa (Förster, 1844) and Taxonus agrorum (Fallén, 1808) (both have n = 10), were studied using fluorescence in situ hybridization (FISH). Chromosomes of both species were demonstrated to contain the canonical TTAGG insect telomeric repeat, which constitutes the first report of the (TTAGG)n telomeric motif for the Tenthredinidae as well as for the clade Eusymphyta and the suborder Symphyta in general. Taken together with the presence of this repeat in many other Holometabola as well as in the hymenopteran families Formicidae and Apidae from the suborder Apocrita, these results collectively suggest the ancestral nature of the (TTAGG)n telomeric motif in the Hymenoptera as well as its subsequent loss within the clade Unicalcarida and independent reappearance in ants and bees. If this is true, the loss of the TTAGG repeat can be considered as a synapomorphy of the corresponding clade.

Nearly complete mitogenome of hairy sawfly, Corynis lateralis (Brullé, 1832) (Hymenoptera: Cimbicidae): rearrangements in the IQM and ARNS1EF gene clusters.

The Cimbicidae is a small family of the primitive and relatively less diverse suborder Symphyta (Hymenoptera). Here, nearly complete mitochondrial genome (mitogenome) of hairy sawfly, Corynis lateralis (Hymenoptera: Cimbicidae) was sequenced using next generation sequencing and comparatively analysed with the mitogenome of Trichiosoma anthracinum. The sequenced length of C. lateralis mitogenome was 14,899 bp with an A+T content of 80.60%. All protein coding genes (PCGs) are initiated by ATN codons and all are terminated with TAR or T- stop codon. All tRNA genes preferred usual anticodons. Compared with the inferred insect ancestral mitogenome, two tRNA rearrangements were observed in the IQM and ARNS1EF gene clusters, representing a new event not previously reported in Symphyta. An illicit priming of replication and/or intra/inter-mitochondrial recombination and TDRL seem to be responsible mechanisms for the rearrangement events in these gene clusters. Phylogenetic analyses confirmed the position of Corynis within Cimbicidae and recovered a relationship of Tenthredinoidea + (Cephoidea + Orussoidea) in Symphyta.

A new xyelotomid (Hymenoptera) from the Middle Jurassic of China displaying enigmatic venational asymmetry.

BACKGROUND: Pterygota insects typically have symmetric veins in left and right wings. For studying taxonomy and phylogeny of fossil insects, venational patterns are commonly used as diagnostic characters, in conjunction with preserved body characters. Some examples of asymmetrical venation are known among extant insects, but only a few fossil insects with asymmetric wings have been reported, among which a previously described xyelotomid of Hymenoptera, Xyelocerus diaphanous, displays an unusual, small cell of vein Rs in the left forewing, but not in the right. RESULTS: Herein we report a new sawfly of the family Xyelotomidae, Aethotoma aninomorpha gen. et sp. nov., from the late Middle Jurassic of China having a simple Sc in the forewing and Sc with two branches in the hind wing. In additional, the new specimen exhibits an enigmatic venational asymmetry. In the right forewing, crossvein 2r-rs of forms a loop, then forks into 2 long branches reaching Rs, while 2r-rs of the left forewing forks into 2 short branches reaching Rs, in contrast to a linear 2r-rs in typical fossil and extant sawflies. CONCLUSION: Such rare asymmetrical venation found from fossil sawflies provides a glance at early occurrences of venational variability and instability, or possibly aberrational development, for insects in the late Middle Jurassic.

A Nonstationary Markov Model Detects Directional Evolution in Hymenopteran Morphology.

Directional evolution has played an important role in shaping the morphological, ecological, and molecular diversity of life. However, standard substitution models assume stationarity of the evolutionary process over the time scale examined, thus impeding the study of directionality. Here we explore a simple, nonstationary model of evolution for discrete data, which assumes that the state frequencies at the root differ from the equilibrium frequencies of the homogeneous evolutionary process along the rest of the tree (i.e., the process is nonstationary, nonreversible, but homogeneous). Within this framework, we develop a Bayesian approach for testing directional versus stationary evolution using a reversible-jump algorithm. Simulations show that when only data from extant taxa are available, the success in inferring directionality is strongly dependent on the evolutionary rate, the shape of the tree, the relative branch lengths, and the number of taxa. Given suitable evolutionary rates (0.1-0.5 expected substitutions between root and tips), accounting for directionality improves tree inference and often allows correct rooting of the tree without the use of an outgroup. As an empirical test, we apply our method to study directional evolution in hymenopteran morphology. We focus on three character systems: wing veins, muscles, and sclerites. We find strong support for a trend toward loss of wing veins and muscles, while stationarity cannot be ruled out for sclerites. Adding fossil and time information in a total-evidence dating approach, we show that accounting for directionality results in more precise estimates not only of the ancestral state at the root of the tree, but also of the divergence times. Our model relaxes the assumption of stationarity and reversibility by adding a minimum of additional parameters, and is thus well suited to studying the nature of the evolutionary process in data sets of limited size, such as morphology and ecology.

The First Fossil Representatives of the Sawfly Genera Emphytus and Empria from the upper Miocene of France (Hymenoptera, Tenthredinidae).

Emphytusmiocenicus sp. nov., first fossil representative of this genus, is described from the upper Miocene of the diatom paleolake of Montagne d'Andance (Ardèche, France). Its placement is ensured by an in-depth comparison with all the extant and fossil genera of the subfamily Allantinae. The representatives of Emphytus are distributed in the Palearctic, Nearctic, and Oriental regions. Empria sammuti sp. nov., second representative of the latter genus, is described from the latest Miocene of the diatom paleolake of Sainte-Reine (Cantal, France). The placement of this new species is based on a detailed comparison with the extant genera of the tribe Empriini. The larvae of the extant Emphytus and Empria spp. are known to be phytophagous on angiosperm leaves of several families, all present as fossils in the taphocenoses of la Montagne d'Andance and Sainte-Reine. Emphytus miocenicus sp. nov. represents the oldest record of this genus and of its crown group, corroborating the estimate of a middle Eocene-middle Oligocene age for its stem group. Throughout our study, it appears that the first described fossil of the genus Empria, E. oligocaenica, from the Oligocene of Germany, needs to be revised and redescribed. It should preferably be treated until the revision as incertae sedis in Allantinae sensu lato.

Taxonomic and biological notes on Pristiphora ribisi Togashi, 1990, (Hymenoptera, Tenthredinidae) injurious to gooseberries and currants.

Taxonomic and biological notes are given for the East Asian sawfly Pristiphora ribisi Togashi, 1990, injurious to Ribes. The following new synonyms of this species are proposed: Pristiphora (Pristiphora) anivskiensis Haris, 2006, syn. nov., Pristiphora (Pristiphora) nigrocoreana Haris Zsolnai, 2007, syn. nov. and Pristiphora grossulariae Anon., 1912 [a primary homonym of Pristiphora grossulariae Walsh, 1866], syn. nov. The lectotype of Pristiphora grossulariae Anon., 1912 is designated. Redescriptions of the adult and immature stages are given. The male is described for the first time. The life history and host plants are summarized. Its close relative, Pristiphora appendiculata (Hartig, 1837), is excluded from the fauna of Japan.

Sex Pheromone of the Introduced Pine Sawfly, Diprion similis, Revisited to Define a Useful Monitoring Lure: Deviating Chiral Composition and Behavioural Responses Compared to Earlier Reports.

Extracts of Diprion similis females contained about 15 ng of the sex pheromone precursor 3,7-dimethylpentadecan-2-ol per female. After derivatisation with (S)-2-acetoxypropanoyl chloride, we found that the major stereoisomer in the extract was (2S,3R,7R)-3,7-dimethylpentadecan-2-ol. Small amounts of other stereoisomers of 3,7-dimethylpentadecan-2-ol were also identified in the extract, namely 1% of (2R,3S,7S), 0.3% (2R,3R,7R) and 0.4% of (2R,3R,7S). An unknown fifth substance showed a very similar spectrum to 3,7-dimethylpentadecan-2-ol, both in SIM and full scan mode. None of the earlier suggested behavioural synergistic isomers ((2S,3S,7S), (2S,3S,7R) and (2S,3R,7S)) were detected in the extracts. In field tests in Ontario, Canada, the earlier identified main pheromone component, viz. the propanoate of (2S,3R,7R)-3,7-dimethylpentadecan-2-ol, was tested alone and in combination with other stereoisomers, earlier reported to be synergistic. No synergistic effects were detected and the threo four-isomer blend was as attractive as the pure main compound. Thus, one of the few examples of a diprionid sawfly using more than one substance in its sex pheromone could not be confirmed. The results also suggest that monitoring programs can use the more easily synthesized threo-blend without losing efficiency. Furthermore, the study suggests that other diprionid pheromones may benefit from a reinvestigation, to clarify possible synergistic effects of stereoisomers.

Hyperxiphia hirashimai, comb. n. (Hymenoptera, Xiphydriidae) from southern Japan: remarkable sexual dimorphism revealed by DNA barcodes and new distribution records.

Based on a study of the type material, Genaxiphia hirashimai Okutani, 1965, a southern Japanese xiphydriid showing remarkable sexual dimorphism, is newly combined with the genus Hyperxiphia Maa, 1949. The previously unknown female is described, and the male is redescribed with additional material. The sexes are associated by examination of specimens of both sexes that apparently emerged from the same piece of branch and by a molecular analysis using mitochondrial COI sequences. Hyperxiphia hirashimai, originally described from Amami-oshima Island, is newly recorded from Miyake-jima Island, southwestern Shikoku, southern Kyushu, Yakushima, Kuroshima and Okinawa-jima Islands.

Caliroa slug sawflies of Japan (Hymenoptera, Tenthredinidae).

Japanese species of Caliroa (Hymenoptera, Tenthredinidae) are the following 13 species, five of which are described as new: C. aizankei Hara, sp. nov. from Hokkaido, C. bibaiensis Hara, sp. nov. from Hokkaido, C. cerasi (Linné, 1758), C. ibukii Hara, sp. nov. from Honshu, C. matsumotonis (Harukawa, 1919), C. nara Hara, 2011, C. nire Hara, sp. nov. from Hokkaido, C. oishii (Takeuchi, 1933), C. ouensis Hara, sp. nov. from Honshu, C. staphyleae Oishi, 1961, C. vaccini Okutani, 1965, C. varipes (Klug, 1816) and C. zelkovae Oishi, 1961. The following two new synonymies are proposed: C. quercivora Togashi, 1999, syn. nov. with C. oishii; C. sumomovora Togashi Oishi, 1978, syn. nov. with C. zelkovae. Lectotypes are designated for C. staphyleae Oishi, 1961 and C. zelkovae Oishi, 1961. Keys to adults and larvae are given. Caliroa staphyleae and C. zelkovae are newly recorded from Hokkaido. New host records are given for C. cerasi and C. zelkovae. Caliroa annulipes (Klug, 1816) is excluded from the fauna of Japan. An additional description of C. annulipes is given. The generic characters are also discussed.

Studies on the related Neotropical genera Acrogymnia Malaise and Dacrogymnia, n. gen. (Hymenoptera: Argidae).

Twenty species of Acrogymnia Malaise and five species of Dacrogymnia Smith Malagón-Aldana, n. gen., both exclusively Neotropical genera, are treated. Acrogymnia occurs from Costa Rica south to Bolivia and southeastern Brazil and Dacrogymnia from southern Colombia to Argentina. The following species are included: Acrogymnia alagoas Smith, n. sp., A. blanki Smith, n. sp., A. brevis Smith, n. sp., A. chapada Smith, n. sp., A. clypea Smith, n. sp., A coxalis (Konow, 1906), A. deulufeuti Smith, n. sp., A. diamantinensis Malaise, 1955, A. fascia Smith, n. sp., A. krylita Smith, n. sp., A. listoni Smith, n. sp., A. lopesi Malaise, 1949, A. palama Smith, 1992, A. pauxilla (Konow, 1906), A. pereirai Smith Malagón-Aldana, n. sp., A. pulla Smith, n. sp., A. pusilla (Malaise, 1937), A. rufina Malaise,1949, A. scutimacula Malaise, 1941, A. transtillata (Konow, 1906), Dacrogymnia acella (Smith, 1992), n. comb., D. imbogea (Smith,1981), n. comb., D. australis Smith, n. sp., D. fernandezi Smith Malagón-Aldana, n. sp., and D. taegeri Smith, n. sp. An identification key for species is provided; however, association of sexes in Acrogymnia is still uncertain for several species.

The first mitogenomes of the superfamily Pamphilioidea (Hymenoptera: Symphyta): Mitogenome architecture and phylogenetic inference.

The Pamphilioidea represents a small superfamily of the phytophagous suborder Symphyta (Hymenoptera). Here, nearly complete mitochondrial genomes (mitogenomes) of three pamphilioid species: Chinolyda flagellicornis (Pamphiliidae), Megalodontes spiraeae and M. cephalotes (Megalodontesidae) were newly sequenced using next generation sequencing and comparatively analysed with the previously reported symphytan mitogenomes. A positive AT skew (0.013) and a negative GC skew (-0.194) were found in pamphilioid mitogenome, and a deviation from strand asymmetry was also observed in the PCGs encoded on both strands. Several gene rearrangement events were observed in four tRNA gene clusters (WCY, IQM, ARNS1EF and TP clusters), which have not been reported from symphytan mitogenomes to date. As the most parsimonious explanation, compared with the inferred insect ancestral mitogenome architecture, the occurrence of gene rearrangements in pamphilioid mitogenomes requires totally five evolutionary steps, including four transpositions and one inversion. The predicted secondary structures of tRNAs, rrnS and rrnL genes are mostly consistent with reported hymenopteran species. Phylogenetic analyses recovered the monophyly of superfamily Pamphilioidea and indicated the relationship Tenthredinoidea + (Pamphilioidea + (Cephoidea + (Orussoidea + Apocrita))) with strong nodal supports.

Gilpinia infuscalae Wang amp; Wei, sp. nov. and a key to the Chinese Gilpinia species (Hymenoptera: Diprionidae).

Gilpinia infuscalae Wang Wei, sp. nov. (Hymenoptera: Diprionidae) from China is described. It is similar in color to G. nigra Okutani, 1958 from Japan but differs in the strongly infuscate wings, the simple inner spur of hind tibia and the unique lancet. The host plant is Pinus massoniana Lamb. (Pinaceae). A key to known species of Gilpinia from China is provided.

First record of the genus Fagineura Vikberg & Zinovjev (Hymenoptera, Tenthredinidae) with descriptions of two new species from China.

Fagineura Vikberg & Zinovjev, 2000 is recorded from China for the first time. Two species of Fagineura are described as new, F.flactoserrula sp. n. and F.xanthosoma sp. n. A key to the species of Fagineura worldwide is provided, now including four species. In addition, a simple phylogenetic analysis of Fagineura species is provided, based on sequences of the COI and NaK genes.

A new sawfly of Megalodontesidae (Insecta, Hymenoptera, Pamphilioidea) with pectinate antennae from the Early Cretaceous of China.

A new sawfly of Megalodontesidae, Jibaissodes peichenae sp. nov., is described from the Lower Cretaceous Yixian Formation of Northeastern China. It is established mainly based on the pectinate antenna comprising 42 flagellomeres and the proximal 28 bearing apical rami, which gradually shorten in length toward the apex of the flagellum. The pterostigma of the forewing is infuscated apically and on the hind wing, vein 1-Rs is nearly equal to 1r-m and slightly shorter than 1-M. The first tergum is widely excised posteriorly and roundly protruding laterally alike in Megalodontes. This find supports that pectinate antennae in extant sawflies of Megalodontesidae originated at least during or before the Early Cretaceous.

Characterization of the mitochondrial genome of Analcellicampa xanthosoma gen. et sp. nov. (Hymenoptera: Tenthredinidae).

A new genus with a new species of the tribe Hoplocampini of Hoplocampinae was described from China: Analcellicampa xanthosoma Wei & Niu, gen. et sp. nov. Hoplocampa danfengensis G. Xiao 1994 was designated as the type species of the new genus. The characters of Analcellicampa danfengensis (G. Xiao) comb. nov. were briefly discussed. A key to the tribes and known genera of Hoplocampinae was provided. The nearly complete mitochondrial genome of A. xanthosoma was characterized as having a length of 15,512 bp and containing 37 genes (22 tRNAs, 13 protein-coding genes (PCGs), and 2 rRNAs). The gene order of this new specimen was the same as that in the inferred insect ancestral mitochondrial genome. All PCGs were initiated by ATN codons and ended with TAA or T stop codons. All tRNAs had a typical cloverleaf secondary structure, except for trnS1. Remarkably, the helices H991 of rrnS and H47 of rrnL were redundant, while helix H563 of rrnL was highly conserved. A phylogeny based on previously reported symphytan mitochondrial genomes showed that A. xanthosoma is a sister group to Monocellicampa pruni, with high support values. We suggest that A. xanthosoma and M. pruni belong to the tribe Hoplocampini of Hoplocampinae.

The West Palaearctic Dineura species, focussing on Sweden (Hymenoptera, Tenthredinidae).

Four Dineura species are now considered to occur in the West Palaearctic, including northern Europe, but D. parcivalvis has not been found in Scandinavia. Dineura pullior Schmidt Walter, 1995 is treated as a new junior subjective synonym of D. virididorsata (Retzius, 1783). An illustrated key to adults is presented. Lectotypes are designated for seven nominal taxa: Dineura stilata var. virilis Enslin, 1918, Dineura testaceipes var. nigriventris Enslin, 1915, Dineura virididorsata var. dorsalis Enslin, 1915, Nematus posticus Förster, 1854, Nematus xanthocerus Hartig, 1840, Nematus xanthopus Zaddach, 1876, and Tenthredo (Allantus) stilata Klug, 1816. Distributions in the Fennoscandian countries are outlined, with particular reference to Sweden.

A review of West Palaearctic Hoplocampa species, focussing on Sweden (Hymenoptera, Tenthredinidae).

Fourteen Hoplocampa species have been recorded in the West Palaearctic. We provide an illustrated key to these species, together with H. tadshikistanica, which is so far only known from Tadshikistan, but could occur in the West Palaearctic. The suitability of genetic sequencing for identification, particularly of larvae, is discussed. COI barcoding reliably distinguishes all European species which have been sampled (only H. phantoma lacks data), except for H. fulvicornis and H. minuta, which can be identified using nuclear sequences. Distributions in the Fennoscandian countries are outlined, with particular reference to Sweden. Hoplocampa chrysorrhoea is recorded for the first time in Scandinavia, from southern Sweden. Lectotypes are designated for twelve nominal taxa: Allantus ferrugineus Panzer, 1802, Hoplocampa chrysorrhoea var. nigrita Enslin, 1914, H. fabricii W. F. Kirby, 1882, H. oertzeni Konow, 1888, H. pectoralis Thomson, 1871, Hylotoma ferruginea Fabricius, 1804, Tenthredo alpina Zetterstedt, 1838, T. brevis Klug, 1816, T. chrysorrhoea Klug, 1816, T. crataegi Klug, 1816, T. plagiata Klug, 1816, and T. rutilicornis Klug, 1816. Hoplocampa minuta forma dudai Gregor, in Gregor Bata, 1942 is a new synonym of H. fulvicornis (Panzer, 1801).

The West Palaearctic Pseudodineura and Endophytus species (Hymenoptera, Tenthredinidae).

Six valid species of Pseudodineura are now recognised as occurring in the West Palaearctic, and the only described species of the related genus Endophytus. Larvae of all species are leaf-miners in Ranunculaceae. An identification key to adults is provided, followed by species commentaries which include summarised data on taxonomy, larval host plants, and distribution, with particular reference to Sweden. Whereas identification of some specimens using morphological characters may not be possible, each species apparently has a distinct COI barcode sequence. Pseudodineura heringi (Enslin, 1921) is a new junior synonym of P. parvula (Klug, 1816). Pseudodineura mocsaryi Zombori, 1976 and P. scaligera Zombori, 1979 are new junior synonyms of P. clematidisrectae Hering, 1935. Lectotypes are designated for: Dolerus minutus Hartig, 1837, Pelmatopus clematidis Hering, 1932, P. enslini Hering, 1923, P. heringi Enslin, 1921, and P. mentiens var. konowi Enslin, 1921.