Phylogeny and historical biogeography of the paper wasp genusPolistes(Hymenoptera: Vespidae): implications for the overwintering hypothesis of social evolution

Mesozoic larva in amber reveals the venom delivery system and the palaeobiology of an ancient lineage of venomous insects (Neuroptera)

The larvae of Neuroptera are predators that feed by injecting bioactive compounds into their prey and then suctioning the fluids through modified mouthparts. We explore the evolutionary history of this feeding structure through the examination of a new fossil larva preserved in Late Cretaceous Kachin amber, which we describe as new genus and species, Electroxipheus veneficus gen et sp. nov. X-ray phase-contrast microtomography enabled us to study the anatomy of the larva in 3D, including the structure of the mouthparts and that of the venom delivery system. The specimen exhibited a unique combination of morphological traits not found in any known fossil or extant lacewing, including an unusual structure of the antenna. Phylogenetic analyses, incorporating a selection of living and fossil larval Neuroptera and enforcing maximum parsimony and Bayesian inference, identified the larva as belonging to the stem group Mantispoidea. The larva shows that the anatomy of the feeding and venom-delivery apparatus has remained unchanged in Neuroptera from the Cretaceous to the present. The morphology of the specimen suggests that it was an active predator, in contrast with the scarcely mobile, specialized relatives, like mantispids and berothids.

The heat shock response in Polistes spp. brood from differing climates following heat stress

Temperature is a crucial factor in many physiological processes, especially in small ectotherms whose body temperature is highly influenced by ambient temperature. Polistes (paper wasps) is a genus of primitively eusocial wasps found in widely varying thermal environments throughout the world. Paper wasps construct open-faced combs in which the brood is exposed to varying ambient temperatures. The Heat Shock Response is a physiological mechanism that has been shown to help cope with thermal stress. We investigated the expression of heat shock proteins in different life stages of three species of Polistes from different climates with the aim of deducing adaptive patterns. This was done by assaying heat shock protein (hsp70, hsp83, hsc70) expression during control conditions (25 °C) or a heat insult (35 or 45 °C) in individuals collected from natural populations in Alpine, Temperate, or Mediterranean climates. Basal expression of hsc70 and hsp83 was found to be high, while hsp70 and hsp83 expression was found to be highly responsive to severe heat stress. As expression levels varied based on species, geographical origin, and life stage as well as between heat shock proteins, the Heat Shock Response of Polistes was found to be complex. The results suggest that adaptive utilization of the heat shock response contributes to the ability of Polistes spp. to inhabit widely different thermal environments.

Characterization of Complete Mitochondrial Genome and Phylogenetic Analysis of a Nocturnal Wasps-Provespa barthelemyi (Hymenoptera: Vespidae)

Genus Provespa contains nocturnal wasps mainly found in the southeastern region of Asia. There are no complete genome resources available of this genus, which hinders the study of its phylogenetic evolution and the origin of nocturnal behavior in the Vespidae family. Through high-throughput sequencing, we obtained the mitochondrial genome of Provespa barthelemyi (Hymenoptera: Vespidae), which is 17,721 base pairs in length and contains 13 protein-coding genes (PCGs), 22 tRNAs, and two rRNAs. We identified four gene rearrangement events of P. barthelemyi that frequently occur in the Vespidae family. We used Maximum Likelihood (ML) methodologies to construct a phylogenetic tree based on the sequenced mitochondrial genome and the available data of reported species belonging to Vespinae. Our findings confirmed the monophyly of Vespinae. Our study reports the first complete mitochondrial genome of Provespa and compares its characteristics with other mitochondrial genomes in the family Vespidae. This research should shed light on the phylogenetic relationships and ecological characteristics of the Vespidae family.

Anaphylaxis after consumption of wasp larvae in Reunion Island: a case report

The practice of entomophagy is common in Asia, Africa, and South America and is now spreading to Europe and the United States. Entomophagy is not without risk since humans can develop allergic reactions to the ingested insects. Here we describe a case of anaphylaxis after consumption of Polistes olivaceus larvae in a 23-y-old man living in Reunion Island, a French overseas department where wasps and other insects are occasionally consumed as part of local traditions. The patient developed diffuse pruritus with facial edema, nausea, and vomiting 15 min after ingesting pan-fried wasp larvae during a dinner with two other people. He was taken to a local care center where he received two oral doses of antihistamines. Shortly after, he presented with shock and hemodynamic, respiratory, and neurological failure. He received a subcutaneous injection of adrenaline and was rapidly transferred to hospital for 12 h of monitoring, after which he was discharged without sequelae. The patient's anaphylactic reaction may have been due only to the allergens contained in the ingested larvae or to cross-allergy. To our knowledge, this is the first reported case of anaphylaxis after consumption of Polistes olivaceus larvae. More generally, few cases of allergic reaction to ingested insects have been described in the literature.

Mitochondrial composition of and diffusion limiting factors of three social wasp genera Polistes, Ropalidia, and parapolybia (Hymenoptera: Vespidae)

Background

Social wasps Polistes, Ropalidia, and Parapolybia, belonging to the subfamily Polistinae, have obviously different distribution patterns, yet the factors leading to this difference remain unknown.

Results

The 17 newly sequenced mitogenomes of Polistes, Ropalidia, and Parapolybia contain 37 genes, and there are obvious differences among the compositions of the three genera. The monophyly of the genus Polistes and a monophyletic Ropalidiini: (Ropalidia + Parapolybia) are concordant with previous morphological analysis of the subfamily Polistinae. Our inferred divergence time demonstrates Polistes (at around 69 Ma) was diverged earlier than Ropalidia and Parapolybia (at around 61 Ma). The rearrangement of both trnY and trnL1 are shared by all the Polistinae. In addition, the unique rearrangement of TDRL derived at 69 Ma is detected in Polistes, and Ropalidia contains a Reversal which may derive at 61 Ma. Hereafter, the possibility is elaborated that Polistes originated in Aisa and then dispersed from Africa to South America, and Polistes and Ropalidia spread from Southeast Asia to Australia. At last, continental drift and Quaternary Ice Ages are inferred to be two main limiting factors in the current distributions of the three genera.

Conclusions

Obvious differences occur in the mitochondrial composition of Polistes, Ropalidia, and Parapolybia. According to the reconstructed time-calibrated framework, it is inquired that the continental drifts and the climate are mainly diffusion limiting factors of the three genera.

Supplementary information

The online version contains supplementary material available at 10.1186/s12862-022-02017-6.

Effect of climate on strategies of nest and body temperature regulation in paper wasps, Polistes biglumis and Polistes gallicus

Polistes paper wasps are a widespread taxon inhabiting various climates. They build nests in the open without a protective outer layer, which makes them vulnerable to changing temperatures. To better understand the options they have to react to environmental variation and climate change, we here compare the thermoregulatory behavior of Polistes biglumis from cool Alpine climate with Polistes gallicus from warm Mediterranean climate. Behavioral plasticity helps both of them to withstand environmental variation. P. biglumis builds the nests oriented toward east-south-east to gain solar heat of the morning sun. This increases the brood temperature considerably above the ambience, which speeds up brood development. P. gallicus, by contrast, mostly avoids nesting sites with direct insolation, which protects their brood from heat stress on hot days. To keep the brood temperature below 40–42 °C on warm days, the adults of the two species show differential use of their common cooling behaviors. While P. biglumis prefers fanning of cool ambient air onto the nest heated by the sun and additionally cools with water drops, P. gallicus prefers cooling with water drops because fanning of warm ambient air onto a warm nest would not cool it, and restricts fanning to nests heated by the sun.

Alternative Nesting Strategies of Polistine Wasps in a Subtropical Locale

Phylogenetic studies suggest that historically all paper wasps (Vespidae: Polistinae) in North America have tropical origins, but some species have adapted to survive temperate conditions. Subtropical climates, which are intermediate between temperate and tropical, allow a unique opportunity to study ancestral traits which can be retained or lost within populations, and ultimately elucidate the process of social wasp evolution. We investigated the phenology of paper wasps at study sites in subtropical Baton Rouge, USA, through nest searching and monitoring of nest parameters throughout the warm season (March-October). Across the year, two periods of nest initiation occurred: from March-May (early season nests, i.e., before the summer solstice), and from July-September (late season nests, after the solstice). We observed 240 Polistes nests from six species, of which 50.8% were initiated in early season and 49.2% in late season. In contrast, Mischocyttarus mexicanus rarely built late season nests and had longer early season colony duration than Polistes bellicosus and P. dorsalis, which built more nests in the late season than early. Across all species, late season nests had significantly shorter colony duration (~87.6 days) than early season nests (~166 days), and only P. bellicosus had fewer adults at peak population in late season nests than in early season nests. Results indicate both a bivoltine colony cycle in Polistes of subtropical climates, as well as differences in nesting strategies between genera.

Life History and the Transitions to Eusociality in the Hymenoptera

Although indirect selection through relatives (kin selection) can explain the evolution of effectively sterile offspring that act as helpers at the nest (eusociality) in the ants, bees, and stinging wasps (aculeate Hymenoptera), the genetic, ecological, and life history conditions that favor transitions to eusociality are poorly understood. In this study, ancestral state reconstruction on recently published phylogenies was used to identify the independent transitions to eusociality in each of the taxonomic families that exhibit eusociality. Semisociality, in which a single nest co-foundress monopolizes reproduction, often precedes eusociality outside the vespid wasps. Such a route to eusociality, which is consistent with groups consisting of a mother and her daughters (subsocial) at some stage and ancestral monogamy, is favored by the haplodiploid genetic sex determination of the Hymenoptera (diploid females and haploid males) and thus may explain why eusociality is common in the Hymenoptera. Ancestral states were also reconstructed for life history characters that have been implicated in the origins of eusociality. A loss of larval diapause during unfavorable seasons or conditions precedes, or coincides with, all but one transition to eusociality. This pattern is confirmed using phylogenetic tests of associations between state transition rates for sweat bees and apid bees. A loss of larval diapause may simply reflect the subsocial route to eusociality since subsociality is defined as females interacting with their adult daughters. A loss of larval diapause and a gain of subsociality may be associated with an extended breeding season that permits the production of at least two broods, which is necessary for helpers to evolve. Adult diapause may also lower the selective barrier to a first-brood daughter becoming a helper. Obligate eusociality meets the definition of a major evolutionary transition, and such transitions have occurred five times in the Hymenoptera.

Marimbondos: systematics, biogeography, and evolution of social behaviour of neotropical swarm-founding wasps (Hymenoptera: Vespidae: Epiponini)

Neotropical swarm-founding wasps are divided into 19 genera in the tribe Epiponini (Vespidae, Polistinae). They display extensive variation in several colony-level traits that make them an attractive model system for reconstructing the evolution of social phenotypes, including caste dimorphism and nest architecture. Epiponini has been upheld as a solid monophyletic group in most phylogenetic analyses carried out so far, supported by molecular, morphological and behavioural data. Recent molecular studies, however, propose different relationships among the genera of swarm-founding wasps. This study is based on the most comprehensive epiponine sampling so far and was analyzed by combining morphological, nesting and molecular data. The resulting phylogenetic hypothesis shows many of the traditional clades but still impacts the way certain behavioural characters, such as nest structure and castes, evolved, and thus requires some re-interpretations. Angiopolybia as sister to the remaining Epiponini implies that nest envelopes and a casteless system are plesiomorphic in the tribe. Molecular dating points to an early tribal diversification during the Eocene (c. 55-38 Ma), with the major differentiation of current genera concentrated in the Oligocene/Miocene boundary.

Reevaluation of the systematic position of some southern Brazilian Discocyrtus (Gonyleptidae:Roeweriinae), with the reinstatement of Bunopachylus

During a study of Discocyrtus Holmberg, 1878 and related genera, several species of alleged Pachylinae, mostly Discocyrtus, from southern Brazil were suspected of belonging in Roeweriinae. Herein, a maximum parsimony phylogenetic analysis of morphological characters was performed to test this hypothesis. Accordingly, the following taxonomic changes are herein proposed: the genus Bunopachylus Roewer, 1943 (currently in Pachylinae) is herein revalidated from synonymy with Discocyrtus, transferred to the Roeweriinae and now includes three species: B. armatissimus comb. nov. (for Discocyrtus armatissimus Roewer, 1913), B. orientalis comb. nov. (for Pachyloides orientalis Roewer, 1913) and B. occultus sp. nov. (which had been misidentified in the literature). A total of five new synonymies are proposed here: Discocyrtus milloti Roewer, 1943 = Discocyrtus coronatus Mello-Leitão, 1935 = Paradiscocyrtus trochanteralis Roewer, 1929 = Discocyrtus calcarifer Roewer, 1917 = Pachyloides orientalis Roewer, 1913, and Bunopachylus magnicalcar Roewer, 1943 (the type-species of Bunopachylus) = Discocyrtus armatissimus Roewer, 1913.

Morphological phylogeny and review of the generic classification of Colletinae (Hymenoptera: Colletidae)

The bee subfamily Colletinae includes 542 species, the vast majority of which (518 spp.) belong to Colletes. The generic placement of the remaining 24 species has been controversial, resulting in several classifications being proposed. Despite several recently published molecular phylogenies of Colletinae, it remains unknown (1) what morphological synapomorphies support the recognized genera, (2) in which direction some relevant functional traits (e.g. basitibial plate) have evolved and (3) whether morphology supports the available molecular data. Herein, we provide a morphological phylogeny of Colletinae, which was constructed through parsimony analyses of 186 characters. In total, 50 ingroup species were included representing all major lineages of Colletes (29 spp.), plus all but three of the non-Colletes species of Colletinae (21 spp.). Trees were estimated through equal weights and extended implied weighting. Both provide strong support for the monophyly of Colletinae and indicate that the subfamily is defined by four unique synapomorphies. Our results also confirm recent phylogenetic hypotheses showing that Colletinae can be subdivided into two major clades: one comprising the reciprocally monophyletic Mourecotelles and Xanthocotelles; the other includes Colletes plus Hemicotelles, which are also reciprocally monophyletic. We also provide a fully illustrated key to facilitate generic identification of the Colletinae.

Complete mitochondrial DNA sequence of the paper wasp Polistes riparius (Hymenoptera: Vespidae)

The paper wasp Polistes riparius is distributed in cold regions of northern East Asia to Russia. P. riparius are characterized by having longer cells than those of the closely related P. chinensis, which has a similar life history, as an adaptation to cold regions. The phylogenetic relationships of paper wasps have recently been studied; however, the genetic diversity and population structure of P. riparius has not been determined. The present study is the first to analyze the complete mitochondrial genome using next generation sequencing of P. riparius collected from Sapporo, Hokkaido Prefecture, Japan. The genome consisted of a closed loop that was 16,383 bp-long and included 13 protein coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one AT-rich control region. The average AT content was 84.54%. The heavy (H)-strand was predicted to have 12 PCGs and 14 tRNA genes, while the light (L)-strand was predicted to contain one PCGs, eight tRNA genes, and two rRNA genes. All PCGs started with ATG. Stop codons were of two types: TAA for 11 genes (ND1, ND2, ND3, ND4L, ND5, ND6, COXI, COXII, COXIII, COB, ATP6 and ATP8) and TAG for two genes (ND3 and ND4). The molecular phylogenetic relationship based on the maximum likelihood method using 13 PCGs was consistent with some previous studies in which a closely relationship between P. riparius and P. jokahamae.

Taxonomy, phylogeny and evolution of the bumblebee bot flies (Oestridae: Hypodermatinae: Portschinskia)

The first phylogenetic study of Portschinskia is presented based on 42 adult morphological characters scored for all 11 species, including four new species Portschinskia burmensis sp. nov., Portschinskia sichuanensis sp. nov., Portschinskia xizangensis sp. nov. and Portschinskia yunnanensis sp. nov.Portschinskia luliangensis is established as a junior synonym of Portschinskia magnifica. Monophyly of Portschinskia is strongly supported by nine non-homoplasious synapomorphies. All cladograms resolve P. yunnanensis as a basal taxon and a well-resolved Portschinskia gigas clade {P. gigas + ((Portschinskia bombiformis + (P. burmensis + (P. magnifica + P. xizangensis))) + (Portschinskia himalayana + (Portschinskia przewalskyi + P. sichuanensis)))}. The only topological difference is Portschinskia loewii and Portschinskia neugebaueri either being sister taxa or branching off successively at the base of the P. gigas clade. Three colour-pattern types are recognized, with the yellow-tailed pattern optimized as the ancestral state. Our data show that the modal colour pattern of Portschinskia species is the same as in bumblebees, and a regional correlation in species diversity and colour patterns can be detected between sympatric Portschinskia and Bombus species. As a result, we suggest that colour patterns of Portschinskia can be explained as Batesian mimicry tracking locally dominant bumblebees.

The complete mitochondrial genome of Orancistrocerusaterrimusaterrimus and comparative analysis in the family Vespidae (Hymenoptera, Vespidae, Eumeninae)

To date, only one mitochondrial genome (mitogenome) in the Eumeninae has been reported in the world and this is the first report in China. The mitogenome of O.a.aterrimus is 17 972 bp long, and contains 38 genes, including 13 protein coding genes (PCGs), 23 tRNA genes, two rRNA genes, a long non-coding region (NCR), and a control region (CR). The mitogenome has 79.43% A + T content, its 13 PCGs use ATN as the initiation codon except for cox1 using TTG, and nine genes used complete translation termination TAA and four genes have incomplete stop codon T (cox2, cox3, nad4, and cytb). Twenty-two of 23 tRNAs can form the typical cloverleaf secondary structure except for trnS1. The CR is 1 078 bp long with 84.69% A+T content, comprising 28 bp tandem repeat sequences and 13 bp T-strech. There are two gene rearrangements which are an extra trnM2 located between trnQ and nad2 and the trnL2 in the upstream of nad1. Within all rearrangements of these mitogenomes reported in the family Vespidae, the translocation between trnS1 and trnE genes only appears in Vespinae, and the translocation of trnY in Polistinae and Vespinae. The absent codons of 13 PCGs in Polistinae are more than those both in Vespinae and Eumeninae in the family Vespidae. The study reports the complete mitogenome of O.a.aterrimus, compares the characteristics and construct phylogenetic relationships of the mitogenomes in the family Vespidae.

Diverse Cretaceous larvae reveal the evolutionary and behavioural history of antlions and lacewings

Myrmeleontiformia are an ancient group of lacewing insects characterized by predatory larvae with unusual morphologies and behaviours. Mostly soil dwellers with a soft cuticle, their larvae fossilize only as amber inclusions, and thus their fossil record is remarkably sparse. Here, we document a disparate assemblage of myrmeleontiform larvae from the mid-Cretaceous amber (99 Ma) of Myanmar, evidence of a considerable diversification. Our cladistic analysis integrating extant and extinct taxa resolves the fossils as both stem- and crown-groups. Similarities between extinct and extant species permit inferences of larval ethology of the fossil species through statistical correlation analyses with high support, implying that morphological disparity matched behavioural diversity. An improved understanding of the evolutionary history of antlions and relatives supports the conclusion that hunting strategies, such as camouflage and fossoriality, were acquired early within the lineage.

A revision of Chilicola (Heteroediscelis), a subgenus of xeromelissine bees (Hymenoptera, Colletidae) endemic to Chile: taxonomy, phylogeny, and biogeography, with descriptions of eight new species

The bee subgenus Chilicola (Heteroediscelis) Toro & Moldenke, 1979 (Hymenoptera, Colletidae, Xeromelissinae) is revised. The subgenus is considered endemic to Chile and occurs across a broad range of habitats. Eight new species are described: Chilicola (Heteroediscelis) charizard Monckton, sp. n., Chilicola (Heteroediscelis) curvapeligrosa Monckton, sp. n., Chilicola (Heteroediscelis) guanicoe Monckton, sp. n., Chilicola (Heteroediscelis) katherinae Monckton, sp. n., Chilicola (Heteroediscelis) lickana Monckton, sp. n., Chilicola (Heteroediscelis) mayu Monckton, sp. n., Chilicola (Heteroediscelis) packeri Monckton, sp. n., and Chilicola (Heteroediscelis) randolphi Monckton, sp. n. One of the existing species, Chilicola (Heteroediscelis) valparaiso Toro & Moldenke, 1979, syn. n., is treated as a junior synonym of Chilicola (Heteroediscelis) mantagua Toro & Moldenke, 1979, and the nine remaining valid species are redescribed. Thoroughly illustrated keys to species for males and females are provided, along with habitus images, images of male terminalia, distribution maps for each species, and a map of relevant Chilean biogeographic regions. Results of phylogenetic analyses are presented, based upon 74 morphological characters and on CO1 barcode sequences, analyzed both separately and as a combined dataset. Monophyly of the subgenus is supported, and groupings within the subgenus are discussed in light of a biogeographic analysis of their species distributions (spatial analysis of vicariance), whereby divergence between taxa is found to occur primarily via north-south disjunctions.