Parasitoid Wasp Species Research Articles

Bracon wasps for ecological pest control-a laboratory experiment.

Biological control of pest insects by natural enemies may be an effective, cheap and environmentally friendly alternative to synthetic pesticides. The cosmopolitan parasitoid wasp species Bracon brevicornis Wesmael and B. hebetor Say (Hymenoptera: Braconidae) use lepidopteran species as hosts, including insect pests like Ephestia kuehniella or Ostrinia nubilalis. Here, we compare the reproductive success of both Bracon species on E. kuehniella in a laboratory experiment. We asked (1) how the reproductive success on a single host larva changes with temperature, (2) how it changes with temperature when more host larvae are present and (3) how temperature and availability of host larvae influence the efficacy of Bracon species as biological control agents. In general, differences between B. brevicornis and B. hebetor have been small. For rearing both Bracon species in the laboratory on one host larva, a temperature between 20–27 °C seems appropriate to obtain the highest number of offspring with a female-biased sex ratio. Rearing the braconid wasps on more than one host larva revealed a higher number of total offspring but less offspring per host larva on average. Again, highest numbers of offspring hatched at 27 °C and the sex ratio was independent from temperature. Although no parasitoids hatched at 12 °C and only few at 36 °C, host larvae were still paralyzed. The efficacy of B. brevicornis was higher than 80% at all numbers of host larvae presented at all temperatures while the efficacy of B. hebetor was less than 80% at 12 °C and 27 °C at low numbers of host larvae presented. In conclusion, practitioners can use either B. brevicornis or B. hebetor at low and high temperatures and at varying host densities to achieve high pest control efficacy.

Telenomus nizwaensis (Hymenoptera: Scelionidae), an important egg parasitoid of the pomegranate butterfly Deudorix livia Klug (Lepidoptera: Lycaenidae) in Oman.

The pomegranate butterfly Deudorix (= Virachola) livia is the major pest of pomegranate, a crop of economic importance, in Oman. A species of parasitoid wasp in the hymenopteran family Scelionidae is responsible for high levels of mortality of its eggs. This wasp is described herein as Telenomus nizwaensis Polaszek sp. n., based on morphology and DNA sequence data. T. nizwaensis is currently known only from D. livia, which is also a pest of economic importance on other crops in North Africa, the Arabian Peninsula, and the Mediterranean. We summarise current knowledge of T. nizwaensis life-history and its potential to provide biological pest control.

Sight of parasitoid wasps accelerates sexual behavior and upregulates a micropeptide gene in Drosophila

Parasitoid wasps inflict widespread death upon the insect world. Hundreds of thousands of parasitoid wasp species kill a vast range of insect species. Insects have evolved defensive responses to the threat of wasps, some cellular and some behavioral. Here we find an unexpected response of adult Drosophila to the presence of certain parasitoid wasps: accelerated mating behavior. Flies exposed to certain wasp species begin mating more quickly. The effect is mediated via changes in the behavior of the female fly and depends on visual perception. The sight of wasps induces the dramatic upregulation in the fly nervous system of a gene that encodes a 41-amino acid micropeptide. Mutational analysis reveals that the gene is essential to the behavioral response of the fly. Our work provides a foundation for further exploration of how the activation of visual circuits by the sight of a wasp alters both sexual behavior and gene expression.

Four new species of parasitoid wasp (Hymenoptera: Braconidae) described through a citizen science partnership with schools in regional South Australia.

Involving the community in taxonomic research has the potential to increase the awareness, appreciation and value of taxonomy in the public sphere. We report here on a trial citizen science project, Insect Investigators, which partners taxonomists with school students to monitor Malaise traps and prioritise the description of new species collected. In this initial trial, four schools in regional South Australia participated in the program and all collected new species of the braconid subfamily Microgastrinae (Hymenoptera: Braconidae). These four species are here described as new, with the names being chosen in collaboration with the participating school students: Choeras ramcomarmorata Fagan-Jeffries Austin sp. nov., Glyptapanteles drioplanetus Fagan-Jeffries Austin sp. nov., Dolichogenidea franklinharbourensis Fagan-Jeffries Austin sp. nov. and Miropotes waikerieyeties Fagan-Jeffries Austin sp. nov. All four species are diagnosed against the known members of the genera from Australia, New Zealand, Fiji, Samoa and Papua New Guinea, and images and COI DNA barcodes are provided of the holotypes. Students had positive feedback about their experiences of the program, and there is significant potential for it to be expanded and used as a means to connect communities with taxonomic science.

Identity of parasitoid wasps (Hymenoptera, Braconidae and Eulophidae) reared from aquatic leaf-mining flies (Diptera, Ephydridae) on invasive Brazilian waterweed Egeria densa in South Africa

The Brazilian waterweed, Egeria densa Planchon, 1849 (Hydrocharitaceae), is an invasive species in South Africa where it is a host plant for the aquatic leaf-miner Hydrellia egeriae Rodrigues-Júnior, 2015 (Ephydridae, Diptera). Efficacy of the biocontrol agent can potentially be affected by parasitoids. Three species of braconid parasitoid wasps were reared from puparia of Hydrellia egeriae. By comparison with the type specimens, these species have been determined to be Ademon lagarosiphonae van Achterberg, 2012 (Braconidae: Opiinae), Chaenusa anervata van Achterberg, 2012 and Chaenusa seminervata van Achterberg, 2012 (Braconidae: Alysiinae: Dacnusini), all previously recorded as parasitoids of an ephydrid dipterous aquatic leaf-miner, Hydrellia lagarosiphon Deeming, 2012, on Lagarosiphon major (Ridley, 1886) Moss ex Wager (Hydrocharitaceae) in South Africa. The chalcidoid, Janicharis africanus Gumovsky & Delvare, 2006 (Eulophidae), was also reared from Hydrellia egeriae and is possibly a hyperparasitoid of the braconids. South Africa is a new country record for J. africanus. We provide comprehensive images of all species including the braconid types and illustrated identification keys to the Afrotropical species of the two braconid genera are also provided. All images and online keys are available on WaspWeb (http://www.waspweb.org).

PRESENCE OF MANTIBARIA SEEFELDERIANA (DE STEFANI) (HYMENOPTERA: SCELIONIDAE) IN CROATIA: A PSEUDOPARASITOID OF PRAYING MANTIS

Herein we present the first record of a very rare species of parasitoid wasp, Mantibaria seefelderiana, in Croatia, with the basic elements of its unusual biology. The most precise categorization of its trophic interaction would be pseudoparasitoid, because the larva of this species feeds on a larger number of mantis embryos in the ootheca in a way that is more representative of predatory diet and behavior, without any regulation by its host’s behavior. Additionally, adult females of this pseudoparasitoid live as ectoparasites attached to the body of female mantises, where they feed on hemolymph. The combination of an unusual predatory and parasitic lifestyle is extremely atypical for the predominantly parasitoid character of most other members of the family Scelionidae.

Bracon wasps for ecological pest control-a laboratory experiment.

Biological control of pest insects by natural enemies may be an effective, cheap and environmentally friendly alternative to synthetic pesticides. The cosmopolitan parasitoid wasp species Bracon brevicornis Wesmael and B. hebetor Say (Hymenoptera: Braconidae) use lepidopteran species as hosts, including insect pests like Ephestia kuehniella or Ostrinia nubilalis. Here, we compare the reproductive success of both Bracon species on E. kuehniella in a laboratory experiment. We asked (1) how the reproductive success on a single host larva changes with temperature, (2) how it changes with temperature when more host larvae are present and (3) how temperature and availability of host larvae influence the efficacy of Bracon species as biological control agents. In general, differences between B. brevicornis and B. hebetor have been small. For rearing both Bracon species in the laboratory on one host larva, a temperature between 20–27 °C seems appropriate to obtain the highest number of offspring with a female-biased sex ratio. Rearing the braconid wasps on more than one host larva revealed a higher number of total offspring but less offspring per host larva on average. Again, highest numbers of offspring hatched at 27 °C and the sex ratio was independent from temperature. Although no parasitoids hatched at 12 °C and only few at 36 °C, host larvae were still paralyzed. The efficacy of B. brevicornis was higher than 80% at all numbers of host larvae presented at all temperatures while the efficacy of B. hebetor was less than 80% at 12 °C and 27 °C at low numbers of host larvae presented. In conclusion, practitioners can use either B. brevicornis or B. hebetor at low and high temperatures and at varying host densities to achieve high pest control efficacy.

Hymenopteran Parasitoids of Hard Ticks in Western Africa and the Russian Far East.

Some parasitoids of the genus Ixodiphagus (Hymenoptera, Chalcidoidea: Encyrtidae) are well-known natural enemies of ticks. In this study, we investigate the occurrence of parasitoid wasps in adult hard ticks from Western Africa (Côte d’Ivoire and Senegal) and Far Eastern Europe (Russia) using molecular methods. The morphological identification allowed the classification of 785 collected specimens of six species of ticks: Rhipicephalus (Boophilus) microplus (41%), Ixodes persulcatus (33%), Dermacentor silvarum (11%), Haemaphysalis concinna (7%), Amblyomma variegatum (5%), and Haemaphysalis japonica (3%). The newly developed MALDI-TOF MS protocol identified tick species in spite of their different storage (dried or in 70% ethanol) conditions for a long period. Molecular screening of ticks by a new standard PCR system developed in this study revealed the presence of parasitoid wasp DNA in 3% (28/785) of analyzed ticks. Ixodiphagus hookeri was detected in 86% (24/28) of infested ticks, including 13 I. persulcatus, 9 R (B) microplus, and one H. concinna and D. silvarum. While an unidentified parasitoid wasp species from the subfamily Aphidiinae and Braconidae family was detected in the remaining 14% (4/28) infested ticks. These infested ticks were identified as I. persulcatus. Our findings highlight the need for further studies to clarify the species diversity of parasitoid infesting ticks by combining molecular and morphological features. The novel molecular and MALDI-TOF MS protocols could be effective tools for the surveillance and characterization of these potential bio-control agents of ticks.

Dataset of host records for introduced parasitoid wasp species (Hymenoptera) in New Zealand.

BackgroundThe introduction of species to new regions is occurring at an increasing rate. These introductions typically consist of species that are deliberately introduced for the purposes of biological control of pests or of species that are accidentally introduced through human-mediated transport networks.Understanding the potential and actual impacts of these introduced species requires comprehensive information on their geographic distributions and biological associations.However, apart from a few well-known case studies, such information is lacking for many introduced species which severely hinders further assessment of risks and impact.New informationA dataset is provided on host associations, geographic distributions and dates of collection for both deliberately and accidentally-introduced parasitoid wasp species (Hymenoptera) in New Zealand. Information was obtained by digitising specimens from the New Zealand Arthropod Collection. Dates of records range from 1921 to 2017.The dataset includes 1265 specimen records, representing 127 parasitoid species from 12 families, with host records for 177 host species from 61 families and eight insect orders.These data provide baseline information to help evaluate the risk from introduced parasitoids to non-target and native species.

Mate attraction, chemical defense, and competition avoidance in the parasitoid wasp Leptopilina pacifica

A major hypothesis for the evolution of chemical signals is that pheromones arise from non-communicative precursor compounds. However, data supporting this hypothesis are rare, primarily because the original functions of the antecedent compounds often have been lost. A notable exception, however, is the parasitoid wasp species Leptopilina heterotoma, whose compound (−)-iridomyrmecin is used as a defensive secretion, a cue for females to avoid competition with con- and hetero-specific females, and as the primary component of the females’ sex pheromone. To better understand the evolution of sex pheromones from defensive compounds, we examined the chemical ecology of L. pacifica, the sister species of L. heterotoma. Here, we show that L. pacifica also produces a defensive secretion containing a species-specific mixture of mostly iridoid compounds. However, the composition of the secretion is more complex than in L. heterotoma, and iridomyrmecin is only a minor component. Moreover, in contrast to L. heterotoma, conspecific female competitors were not avoided by female subjects, and a role of the iridoids in the female sex pheromone of L. pacifica can be excluded, as only the females’ cuticular hydrocarbons (CHCs) resulted in the elicitation of courtship by males. Although closely related, the two sister species show substantial differences in the use of the defensive secretion for communicative purposes. Variation in pheromone usage in this genus still presents a conundrum, highlighting the need for additional studies to understand the selective forces shaping the evolution of pheromone composition.

Non-consumptive effects stabilize herbivore control over multiple generations.

Understanding the factors that influence predator-prey dynamics requires an investigation of oscillations in predator and prey population sizes over time. However, empirical studies are often performed over one or fewer predator generations. This is particularly true for studies addressing the non-consumptive effects of predators on prey. In a previous study that lasted less than one predator generation, we demonstrated that two species of parasitoid wasps additively suppressed aphid populations through a combination of consumptive and non-consumptive effects. However, the non-consumptive effects of one wasp reduced the reproductive success of the other, suggesting that a longer-term experiment may have revealed antagonism between the wasps. The goal of our current study is to evaluate multi-generation consumptive and non-consumptive interactions between pea aphids (Acyrthosiphon pisum) and the wasps Aphidius ervi and Aphidius colemani. Aphidius ervi is a common natural enemy of pea aphids. Aphidius colemani is a non-consumptive enemy that does not consume pea aphids, but negatively affects pea aphid performance through behavioral disturbance. Large field cages were installed to monitor aphid abundance in response to the presence and absence of both species of wasp over four weeks (two parasitoid generations). We found that the non-consumptive enemy A. colemani initially controlled the pea aphid population, but control in the absence of parasitism was not sustainable over the long term. Aphidius ervi suppressed pea aphids through a combination of consumptive and non-consumptive effects. This suppression was more effective than that of A. colemani, but aphid abundance fluctuated over time. Suppression by A. ervi and A. colemani together was complementary, leading to the most effective and stable control of pea aphids. Therefore, promoting a diverse natural enemy community that contributes to pest control through consumptive and non-consumptive interactions may enhance the stability of herbivore population suppression over time.

Phylogeny, taxonomics, and ovipositor length variation of thePteromalus albipennisspecies group (Hymenoptera: Chalcidoidea: Pteromalidae: Pteromalinae)

The Pteromalus albipennis species group currently comprises 29 Palaearctic parasitoid wasp species associated with tephritid fly larvae developing in flower heads of Asteraceae. The species group is taxonomically challenging, because its putative species are morphologically extremely similar to each other except for some conspicuous differences in gaster length, which is a reliable proxy for the ovipositor length. Ovipositor length dictates the accessibility of host larvae to the parasitoid female and thus largely determines the host range of a species. In this study, we infer the phylogenetic relationships of currently recognized species of the P. albipennis species group by analyzing the nucleotide sequences of 124 protein-coding genes spanning more than 310,000 bp. The data were analyzed by applying the maximum likelihood optimality criterion (concatenated sequence data) as well as a multispecies coalescent approach (analyzing gene trees). Based on the inferred species trees, we (a) re-evaluate previous species hypotheses in comparison with the new phylogenomic results and (b) assess whether or not ovipositor length variation is phylogenetically constrained. Our results show some incongruence between morphology-based and phylogenomics-based species delimitations and suggest the existence of paraphyletic species. Furthermore, our study suggests that ovipositor length is no reliable predictor of phylogenetic relatedness, but a labile trait, possibly reflecting rapid evolution of host range differences. Taxonomic ambiguities and the scarce knowledge on the biology of the analyzed species highlight the difficulties of studying parasitoid wasps, even in the Western Palaearctic, and despite the application of integrative taxonomics approaches (i.e., the use of hundreds of genes for taxonomy).

Do plant volatiles confuse rather than guide foraging behavior of the aphid hyperparasitoid Dendrocerus aphidum?

Many species of parasitoid wasps use plant volatiles to locate their herbivorous hosts. These volatiles are reliable indicators of host presence when their emission in plants is induced by herbivory. Hyperparasitoids may also use information from lower trophic levels to locate their parasitoid hosts but little is known about the role of volatiles from the plant–host complex in the foraging behavior of hyperparasitoids. Here, we studied how Dendrocerus aphidum (Megaspilidae) responds to plant and host volatiles in a series of experiments. This hyperparasitoid uses aphid mummies as its host and hampers biological control of aphids by parasitoids in greenhouse horticulture. We found that D. aphidum females were strongly attracted to volatiles from mummy-infested sweet pepper plants, but only when clean air was offered as an alternative odor source in the Y-tube olfactometer. Hyperparasitoid females did not have a preference for mummy-infested plants when volatiles from aphid-infested or healthy pepper plants were presented as an alternative. These olfactory responses of D. aphidum were mostly independent of prior experience. Volatiles from the host itself were also highly attractive to D. aphidum, but again hyperparasitoid females only had a preference in the absence of plant volatiles. Our findings suggest that plant volatiles may confuse, rather than guide the foraging behavior of D. aphidum. Mummy hyperparasitoids, such as D. aphidum, can use a wide variety of mummies and are thus extreme generalists at the lower trophic levels, which may explain the limited role of (induced) plant volatiles in their host searching behavior.

A new biological method to control Anobium punctatum, by using the parasitoid wasp Spathius exarator

AbstractBiological pest control by means of beneficial organisms is for long part of agriculture and Integrated Pest Management (IPM). A new and efficient strategy to control the most common timber pest species in churches and museums, the furniture beetle Anobium punctatum (De Geer) (Coleoptera: Anobiidae), is based on the parasitoid wasp species Spathius exarator (Linnaeus) (Hymenoptera: Braconidae). Once this braconid wasp detects its host species beneath the surface, it pierces the wood with its ovipositor to lay one single egg onto the beetle larva. After hatching, the wasp larva feeds on the beetle larva thereby killing it. Afterwards, it pupates and emerges through a self‐gnawed hole as an adult wasp. The tiny, 0.5‐mm‐wide exit hole can easily be distinguished from the 1‐ to 2‐mm‐wide exit hole of A. punctatum. Laboratory tests revealed that female wasps have an average life span of 85 days and produce a total of 24 offspring, when nutrition is provided. Between 2012 and 2019, braconid wasps were introduced into 54 different A. punctatum infested buildings. Treatment success was monitored by examining exit holes of new beetles and wasps thereby calculating corresponding parasitism rates. After the first year of treatment, parasitism rates were significantly higher with a mean value of 0.15 when compared to untreated objects with a natural parasitism and a mean value of 0.08 (n = 54). Following treatment of three objects over a period of eight years, parasitism rates continuously increased from 0.02 up to 0.31. In a church organ, which was treated during this period, the monitoring revealed a complete suppression of pest activity. These data prove that this biological method of pest control is an efficient, sustainable and non‐toxic option to manage the common furniture beetle.

Life history of aggression in Anastatus disparis (Hymenoptera: Eupelmidae) with extreme male-male combat.

Aggressive behaviour is common in animals and typically has lifetime consequences. As younger males have higher residual reproductive value than older males and lose more from injuries than older males do, the propensity for fighting tends to increase with age in many empirical reports and species. However, fighting patterns in those empirical reports cannot confirm the hypothesis that individuals cannot readily inflict injuries on their opponents. To address this shortcoming, a parasitoid wasp species, Anastatus disparis (Hymenoptera: Eupelmidae), was used as an experimental model to explore the characteristics of aggression from a life-history perspective; this wasp exhibits extreme fighting, resulting in contestants experiencing injury and death. Results showed that the energetic costs of fighting to injury significantly shortened life and caused the loss of most mating ability. Inconsistent with general predictions, the frequency and intensity of fighting in A. disparis significantly decreased with male age. Further study results showed significantly more young males were received by and successfully mated with virgin females, and most genes related to energy metabolism were downregulated in aged males. Our study provided supporting evidence that young A. disparis males show more aggression likely because of their resource holding potential and sexual attractiveness decline with age.

New species of Stenomacrus (Hymenoptera: Ichneumonidae: Orthocentrinae) reared from Bradysia impatiens (Diptera: Sciaridae) in The Netherlands

ABSTRACT A new parasitoid wasp species, belonging to the genus Stenomacrus (Hymenoptera: Ichneumonidae: Orthocentrinae), was found in several Dutch plant nurseries. Here we describe, illustrate and discuss the biology, morphology and molecular characterisation of Stenomacrus meijeri sp. nov. It was reared from < 24 h old larvae of the fungus gnat Bradysia impatiens (Diptera: Sciaridae). http://www.zoobank.org/urn:lsid:zoobank.org:pub:DB48ABEC-2429-4C51-8297-A23D11DC4DF9

Cuticular Hydrocarbons as Contact Sex Pheromone in the Parasitoid Wasp Urolepis rufipes

The cuticle of virtually any insect is covered by a thin layer of cuticular hydrocarbons (CHCs) typically consisting of a complex mixture of n-alkanes, methyl-branched alkanes, and unsaturated hydrocarbons. Apart from their putative primary function as a desiccation barrier, CHCs are used by insects for communication. In many species of parasitoid wasps, males use CHCs to recognize females, and thus the composition of CHC profiles is typically species- and sex-specific. Sometimes, the biological activity of CHCs is synergized by more polar lipids. In most species, however, the contribution of polar lipids and the role of individual CHCs or CHC classes is unclear. Here we report a CHC-based contact sex pheromone in the pteromalid wasp Urolepis rufipes. Males of U. rufipes were arrested on and showed courtship behavior (wing fanning) and copulation attempts towards cadavers of females, whereas male cadavers and solvent-washed cadavers of either sex elicited no responses. Whole body extracts from females and the non-polar CHC fraction thereof elicited arrestment, courtship, and copulation attempts by males, whereas the fractions containing polar lipids were behaviorally inactive. Analyses of male- and female-derived CHC profiles revealed that they consisted exclusively of n-alkanes and methyl-branched alkanes. Removal of n-alkanes from female-derived CHCs with molecular sieves rendered the remaining methyl-branched fraction inactive. Synthetic n-alkanes in female-specific ratios also did not elicit any responses by males. Two 7-methylalkanes (7-MeC31 and 7-MeC33) were the only two components with a higher relative abundance in females compared to males. However, supplementation of male-derived CHCs with synthetic racemic 7-MeC31 and 7-MeC33 to levels found in females was not sufficient to render male-derived CHCs attractive to males. Enantiopure synthetic 7-MeC31 and 7-MeC33 might have caused different effects but were not available. We conclude that female-derived CHCs function as a contact sex pheromone in U. rufipes. Our data suggest that methyl-branched and n-alkanes act synergistically and that the sex-specific relative composition of the whole profile, rather than the abundances of single components, underlies the elicitation of male courtship behavior.

G-OnRamp: Generating genome browsers to facilitate undergraduate-driven collaborative genome annotation.

Scientists are sequencing new genomes at an increasing rate with the goal of associating genome contents with phenotypic traits. After a new genome is sequenced and assembled, structural gene annotation is often the first step in analysis. Despite advances in computational gene prediction algorithms, most eukaryotic genomes still benefit from manual gene annotation. This requires access to good genome browsers to enable annotators to visualize and evaluate multiple lines of evidence (e.g., sequence similarity, RNA sequencing [RNA-Seq] results, gene predictions, repeats) and necessitates many volunteers to participate in the work. To address the technical barriers to creating genome browsers, the Genomics Education Partnership (GEP; https://gep.wustl.edu/) has partnered with the Galaxy Project (https://galaxyproject.org) to develop G-OnRamp (http://g-onramp.org), a web-based platform for creating UCSC Genome Browser Assembly Hubs and JBrowse genome browsers. G-OnRamp also converts a JBrowse instance into an Apollo instance for collaborative genome annotations in research and educational settings. The genome browsers produced can be transferred to the CyVerse Data Store for long-term access. G-OnRamp enables researchers to easily visualize their experimental results, educators to create Course-based Undergraduate Research Experiences (CUREs) centered on genome annotation, and students to participate in genomics research. In the process, students learn about genes/genomes and about how to utilize large datasets. Development of G-OnRamp was guided by extensive user feedback. Sixty-five researchers/educators from >40 institutions participated through in-person workshops, which produced >20 genome browsers now available for research and education. Genome browsers generated for four parasitoid wasp species have been used in a CURE engaging students at 15 colleges and universities. Our assessment results in the classroom demonstrate that the genome browsers produced by G-OnRamp are effective tools for engaging undergraduates in research and in enabling their contributions to the scientific literature in genomics. Expansion of such genomics research/education partnerships will be beneficial to researchers, faculty, and students alike.

Male morphology, performance and female mate choice of a swarming insect

Females of many species select mates based on important morphological and performance traits. This behaviour likely facilitates reproductive success thus exhibiting sexual selection. Most such studies have evaluated a single morphological variable, and only a minority of them studies the effects of behaviour and performance (functional capacity: Irschick et al., Evolutionary Ecology Research, 10, 177–196, 2008) at all. This study compares male morphological and performance traits differing in three variables that may correlate with fitness: condition index, flight ascent speed and resistance to torpor in relation to male mating success in the parasitoid wasp species Alabagrus texanus (Braconidae), a species where males swarm about emerging virgin females that display both choosy and non‐choosy behavioural phenotypes. Males that successfully mated with choosy females exhibited higher condition indices and somewhat stronger resistance to torpor than other males. Conversely, males that mated with non‐choosy females did not differ in any trait from other males we measured. Early‐arriving males did not have higher condition indices or greater mating success than other males. Thus, both morphological and performance traits contributed to male success, which acted through female choice, indicating a role for sexual selection. Patterns of choice further differed among females, independent of male traits.

A Protocol to Identify the Host of Parasitoids by DNA Barcoding of Vestigial Tissues

Many parasitoid wasps parasitize herbivorous insect larvae growing within plant organs (e.g., fruits and leaves). As it is hard to identify the insect host species directly, one approach to deal with this issue is to identify it by means of molecular analysis from puparia left within plant organs after wasps emerge. Unfortunately, current barcoding methods are either too expensive or too inefficient for mass species identification. Here, we present a protocol that is comparatively inexpensive and rapid. It includes two major modifications in the barcoding process. One is to use a modified Chelex DNA extraction method, which performed best in PCR amplification and was the least costly and time-consuming among four candidate methods. The other is to use general PCR primers for the host taxon, which had the highest sequencing success rate when coupled with the Chelex DNA extraction method. Our protocol proved to be successful in identifying the hosts (i.e., tephritid fly species) of parasitoid wasps in a Tibetan alpine meadow. The protocol can be widely used for mass identification of insect host species from puparia tissues to facilitate the studies on host–parasitoid interactions.