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The insect parasitoid, Pediobius imbreus (Hymenoptera: Eulophidae), which has a diverse host range, probably possesses various antennal sensilla (sensory organs) to assist the parasitoid in host searching and ensuring its survival. In this study, we aimed to investigate the distribution and morphology of the antennal sensilla of both female and male P. imbreus using scanning electron microscopy (SEM). SEM results revealed that P. imbreus has seven antennomeres on its geniculate antenna, which is composed of scape, pedicel, and five flagellomeres. Numerous antennal sensilla types were observed on the P. imbreus antennae: trichoid sensilla types 1–8; placoid sensilla types 1–2; and basiconic sensilla. The female P. imbreus exhibits a greater abundance of sensilla on both its dorsal and ventral surfaces compared to the male. The trichoid sensilla are the most abundant sensillum type found on the antennae of P. imbreus, followed by placoid sensilla and basiconic sensilla. By comparison, the female P. imbreus have more diverse types of sensilla, which are longer than that of male. Overall, the female antenna and its trichoid sensilla type 6 are significantly (P < 0.05) longer than that of the male. The male P. imbreus does not have trichoid sensilla type 8 and placoid sensilla type 2. The potential roles of the antennal sensilla in host detection based on their location and morphology will be discussed. The knowledge obtained will aid future research on the host localization in P. imbreus. [ABSTRACT FROM AUTHOR]

Galls are thought to be induced by insects for protection, yet many gall‐forming insects experience heavy parasitization. Little is known about how parasitoids locate gall‐forming insects. Quadrastichus mendeli Kim & La Salle (Hymenoptera: Eulophidae) is an obligate ectoparasitoid of the larvae of Leptocybe invasa Fisher et La Salle (Hymenoptera: Eulophidae), which is an invasive gall‐forming pest in eucalyptus (Eucalyptus spp., Myrtaceae) plantations. In this study, Q. mendeli and L. invasa were used to explore parasitoid behavior when locating gall‐forming insects. Our results revealed that host location by Q. mendeli involved five discrete steps: walking, resting or grooming, antennating, probing and stinging. Antennation was the most frequent behavior, accounting for about half of the total time. Host location behavior of Q. mendeli occurred in the photophase. Female Q. mendeli exhibited a clear circadian rhythm: Almost all behaviors occurred during the photophase, and behavior peaked at the sixth hour of the light phase. The olfactory response rates of Q. mendeli to volatiles from galls decreased significantly after their antennae were detached. However, there was no significant difference in the host location behavior of Q. mendeli after their eyes were obscured. Our results provide essential information to explore the host location mechanisms in gall parasitoids. [ABSTRACT FROM AUTHOR]

Leaves of field elm, Ulmus minor, with mines of Orchestes alni, were collected at four sites in Sofia city during 2018, 2019 and 2023, and kept under laboratory conditions to observe and count emerging parasitoid adults. Results revealed that the parasitoid complex included 22 hymenopteran species belonging to five families: Braconidae (two species), Ichneumonidae (one species) (Ichneumonoidea), Eulophidae (14 species), Eupelmidae (three species) and Pteromalidae (two species) (Chalcidoidea). The most abundant species was Pnigalio agraules (27%), followed by Minotetrastichus platanellus (18%) (Eulophidae) and Trichomalus inscitus (Pteromalidae) (14%). Nine host–parasitoid associations are reported as new. Tetrastichus miser is reported from Bulgaria for the first time. These findings are discussed in relation to the known host–parasitoid associations of the genus Orchestes. The identification of the host species, O. alni, was supported by both morphological and molecular methods. [ABSTRACT FROM AUTHOR]

During the period 2019-2020, parasitoids of invasive oak lace bug (Corythucha arcuata) were studied in Bulgaria. Biological material (larvae of C. arcuata) was collected from European oak (Quercus robur) or Austrian oak (Quercus cerris) in five localities of the country. Five eulophid specimens (Hymenoptera: Eulophidae) were reared from the host larvae: Tamarixia pubescens, Elasmus sp., Minotetrastichus sp., Pnigalio sp. and Sympiesis sp. The impact of the parasitoids on the host number was very low (0.1-0.3%). The present records in Bulgaria are the first documented case of adaptation of native parasitoids to the host in the newly occupied areas in Europe and Asia.

The common name 'Ferguson squathopper' is proposed for Messena sinuata Atkinson (Eurybrachidae). Cycas circinalis L. (Cycadaceae), Mangifera indica L. (Anacardiaceae), Pongamia pinnata (L.) Merr. (= Millettia pinnata (L.) Panigrahi), Samanea saman (Jacq.) Merr.) (both Fabaceae), Terminalia catappa L., T. paniculata Roth (Combretaceae) and Tectona grandis L. f. (Verbenaceae) are newly recorded as host plants of M. sinuata. Messena albifasciata Distant is possibly a junior synonym of M. sinuata. Hymenopteran parasitoids Proleurocerus litoralis Hayat and Kazmi (Encyrtidae, Encyrtinae), Parachrysocharis malabarensis Narendran (Eulophidae, Tetrastichinae) and an unnamed Anastatus sp. (Eupelmidae: Eupelminae) (males only) are newly reported as egg parasitoids of M. sinuata. All parasitoids are described with illustrations. The hitherto unknown male of Parachrysocharis malabarensis is described. Notes on parasitisation are provided. [ABSTRACT FROM AUTHOR]

A survey of the parasitoid species of the citrus leafminer (CLM), Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), a cosmopolitan pest of citrus, was carried out in 2019 and 2020 in the major citrus production area of Tunisia. Four different Eulophidae species were found: Citrostichus phyllocnistoides (Narayanan), representing 81.82% of the identified parasitoids, Semielacher petiolatus (Girault) (9.40%) and the native species Pnigalio pectinicornis (L.) (2.82%). Cirrospilus ingenuus Gahan (Hymenoptera: Eulophidae) is a new report for the parasitoid entomofauna of P. citrella in the country, representing 5.96% of the identified parasitoids. It has probably spread naturally from other Mediterranean regions. Predation by generalist predators is the main mortality factor of CLM (up to 59.11% of the mortality was caused by natural enemies), followed by parasitism (oviposition) (22.47%) and host-feeding (18.42%). Second and third instar larvae of the CLM were the preferred stages for parasitism. Host-feeding and generalist predators' attacks were most common on first and second instars. Data highlighting the ability for C. phyllocnistoides to develop and disperse clearly predominates in Tunisian citrus orchards. Citrostichus phyllocnistoides may compete with S. petiolatus, exerting a complementary action to that of C. phyllocnistoides, particularly earlier in the season when the densities of the latter species are low. Further studies focusing on inter-specific relationships between these two exotic parasitoids are needed in order to test whether the observed field results could have been estimated from laboratory assays. This will be helpful in critically evaluating the results of the classical biological control programme developed against CLM in Tunisia. [ABSTRACT FROM AUTHOR]

Simple Summary: Competition arises for the monopolization of host resources when multiple parasitoid species attack the same host. This study focused on the competition between Chouioa cunea Yang and Tetrastichus septentrionalis Yang (Hymenoptera: Eulophidae), two pupal parasitoid species of the fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Erebidae). Experiments were conducted to investigate extrinsic and intrinsic competition. The results showed that both parasitoid species were capable of parasitizing hosts that were already parasitized by the competitor, with the first released species demonstrating superiority as an intrinsic competitor in multiparasitized hosts across various parasitoid release orders and time intervals between oviposition. These findings contribute to a better understanding of the interactions between the two parasitoids within the host pupae and offer insights into the biological control of H. cunea and other leaf-eating pests. The endoparasitoids Chouioa cunea Yang and Tetrastichus septentrionalis Yang (Hymenoptera: Eulophidae) are both gregarious pupal parasitoids of the fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Erebidae). In order to analyze the competitive interactions between both parasitoids exploiting H. cunea, we assessed both extrinsic and intrinsic competition. The search time, oviposition duration, and oviposition frequency were used as evaluation criteria for extrinsic competition. The number of survival days, female ratio, and number of parasitoids emerging from the host were used as evaluation criteria for intrinsic competition. The results indicated that both parasitoid species were able to parasitize hosts that were already parasitized by competitors. The first released species consistently emerged as the superior competitor in multiparasitized hosts. Both parasitoid release orders and time intervals between oviposition affect the competition of parasitoids and the parasitic efficiency. The results emphasize the parasitic abilities of both parasitoid species and provide a basis for future research on competition mechanisms and biological control of H. cunea. [ABSTRACT FROM AUTHOR]

Soybeans are a valuable crop in many countries of the world. To obtain stable yields, it is necessary to consider the activities of arthropods, both beneficial and destructive. The results of this study indicate high biodiversity. Most of the insects that feed on soy are polyphagous. In the years favorable for their development, omnivorous pests pose a serious threat to soybeans. The species composition of arthropods on soybeans of the Krasnodar and Stavropol territories of the Russian Federation during the years of the study was represented by 212 species (210 species of insects and 2 species of mites), including 101 species of phytophagous insects, which accounted for 48.5% of the total fauna and 109 species of entomophagous insects (51.7%). Most of the entomophages were parasitic Hymenoptera belonging to such families as Ichneumonidae, Braconidae, Aphidiidae, Eurytomidae, Ormyridae, Pteromalidae, Encyrtidae, Eupelmidae, Eulophidae, Elasmidae, Scelionidae, Platygastridae, and Chrysididae. The most numerous phytophagous insects damaging soybeans belonged to the Hemiptera order (34 out of 101 species of phytophages). The Lepidoptera order in the soybean agrocenosis was represented by 28 species (13.4% of the total fauna and 28.0% of the destructive fauna). [ABSTRACT FROM AUTHOR]

Simple Summary: Parasitic wasps are natural enemies of numerous significant agricultural and forestry pests and therefore play an important role in biological control. With the development of integrative taxonomy, a greater variety of techniques are being applied to species identification. Therefore, integrated taxonomy was utilized in this study to identify parasitic wasps. Xinjiang is the largest province in China in terms of land area. However, the resources and environmental adaptation characteristics of Chalcidoidea have been little researched. In this study, we utilized geometric morphometrics and COI gene haplotype analysis and found that the morphology and genetic differentiation of Chalcidoidea changed at different altitudes. Eulophidae and Pteromalidae are parasitic wasps with a global distribution and import for the biological control of pests. They can be distributed in different altitude regions, but their morphological and genetic adaptations to different altitudes are unclear. Here, we collected specimens that belong to Eulophidae and Pteromalidae from various altitudinal gradients, based on integrated taxonomic approaches to determine the species composition, and we analyzed their body shape and size from different altitudes using geometric morphometrics. Then, we performed an analysis of the D. isaea population's haplotype genes to illustrate their genetic diversity. As a result, eight species that belong to two genera, Diglyphus Walker (Eulophidae) and Pachyneuron Walker (Pteromalidae), were identified, including two newly recorded species from China (D. chabrias and D. sabulosus). Through a geometric morphometrics analysis of body shape, we found that a narrow forewing shape and a widened thorax are the significant characteristics of adaptation to high-altitude environments in D. isaea and P. aphidis. Additionally, the body size studies showed a principal relationship between centroid size and altitude; the size of the forewings and thorax increases at higher altitudes. Next, using haplotype analysis, 32 haplotypes were found in seven geographic populations with high genetic diversity of this species. Our research provides preliminary evidence for the morphological and genetic diversity adaptation of parasitic wasps to extreme environments, and these data can provide important references for investigations on the ecological adaptability of parasitic wasps. [ABSTRACT FROM AUTHOR]

Hymenopteran parasitoids strongly associated with the sugarcane borer [Diatraea saccharalis (Lepidoptera: Crambidae)] may be found both in organic and conventional sugarcane farming systems. This study aimed to sample parasitoids associated with sugarcane borer in organic, organic near a forest fragment and conventional systems. Two colors of Moericke traps were used (yellow and white) to collect insect samples, and faunistic analyses were performed to determine the composition of parasitoids in each management type. A total of 287 insects were collected, with the most abundant families being Diapriidae (44.44 %), Eulophidae (37.5 %) and Braconidae (18.06 %). The most abundant genus in the organic system was Omphale (Eulophidae), Omphale (Eulophidae) in the organic system near the forest fragment, and Omopria and Coptera (Diapriidae) in the conventional system. The parasitoids were more abundant in the organic system (43.06 %), followed by the organic system near the forest fragment (36.81 %) and the conventional system (20.14 %). The yellow trap was the most effective in attracting parasitoids, which were generally more abundant in organic systems, regardless of proximity to forest fragments.

Competition between parasitoids for available hosts is common in insects. These interactions are often negative and are believed to reduce the overall impact of top‐down population regulation. In the spruce budworm, Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae), two parasitoid species are very common and often interact during the period of low‐density populations between outbreaks: the koinobiont endoparasitoid Tranosema rostrale (Brishke) (Hymenoptera: Ichneumonidae) and the idiobiont ectoparasitoid Elachertus cacoeciae (Howard) (Hymenoptera: Eulophidae). Data collected from field‐implanted larvae of spruce budworm exposed in summer during a 35‐year period between 1987 and 2022 were used to estimate the response of these two parasitoids to the density of their spruce budworm host, and the nature and importance of competitive interactions between them. It was found that both parasitoids are most effective at very low host population density, and that a strong, density‐dependent, and negative correlation of frequencies exists between them. This negative correlation is evident both among and within years and indicates that the parasitoids have developed seasonal history and host choice behaviors that tend to minimize the negative impact of direct competition on their respective performance. It appears that the koinobiont T. rostrale manages, through those adaptive strategies, to avoid direct competition inside a larval host with the competitively superior idiobiont E. cacoeciae. [ABSTRACT FROM AUTHOR]

Simple Summary: Chalcidoidea (chalcid wasps) are one of the most numerically, structurally, and biologically diverse groups in Hymenoptera. However, the conserved morphology coupled with a high intraspecific variability in certain key characters hinders research on chalcids. In this study, DNA barcoding with the COI gene was used to calibrate intra- and interspecific variation in diagnostic characters within the genus Dzhanokmenia. In addition, the nuclear gene, 28S D2, was used to infer a phylogeny to better understand the definition of Dzhanokmenia and its relationships to potentially close genera associated with Tetrastichus. A DNA barcode library that includes eight species was established for Dzhanokmenia. A new species, D. brevifunis Ganbaatar & Cao sp. nov., was described and illustrated. The results show that Dzhanokmenia is closely related to Baryscapus and suggest that the species diversity of Dzhanokmenia is underestimated. This study lays a foundation for further research on the diversity and classification of Dzhanokmenia. Although Chalcidoidea is one of the megadiverse superfamilies in Hymenoptera, numerous species are still being discovered and described. However, the difficulties in delimiting intra- and interspecific variation hinder this process. In this study, DNA barcoding methods using the COI gene were employed to investigate the morphological variation within Dzhanokmenia Kostjukov, 1977. The nuclear locus, 28S D2, was used to infer a phylogeny to gain an understanding of the relationship of Dzhanokmenia with other potentially close genera. Through a preliminary DNA barcode library established here, including eight species, we calibrated the intraspecific variation in certain diagnostic characters for the new species described here, D. brevifunis Ganbaatar & Cao sp. nov. Maximum likelihood results show that Dzhanokmenia is clustered with the genera associated with Tetrastichus, such as Chaenotetrastichus Graham, 1987, Baryscapus Förster, 1856, Tetrastichus Haliday, 1844, and Oomyzus Rondani, 1870 involved in this study. Our results indicate that the species diversity of Dzhanokmenia is understudied and tentatively confirm that Dzhanokmenia has a potential close relationship with Baryscapus. Along with the DNA barcode library, the referenced phylogeny datasets improve the understanding of the systematic position of Dzhanokmenia within the subfamily Tetrastichinae and the definition of this genus in terms of morphology, thereby facilitating species delimitation, discovery, and description within Dzhanokmenia. [ABSTRACT FROM AUTHOR]

A new species of the genus Chrysonotomyia Ashmead, Chrysonotomyia susbelli sp. nov., is described from the Rice University campus in Houston, Texas, USA. The species is a parasitoid emerging from Neuroterus nr. bussae galls in leaves of the southern live oak (Quercus virginiana). This represents the 6th species described from North America north of Mexico and the first in the world known to parasitize cynipid gall wasps. This discovery hints at an entire undiscovered niche between Chrysonotomyia parasitoids, cynipid gall wasps, and oaks in the Nearctic, which is a global biodiversity hotspot for oaks and cynipids. This new species description is complemented by mtDNA-COI-barcode data and information on the natural history of this species. We record host association, phenology, and report a leaf-scanning behavior performed by females, presumably to search for host galls. Modifications to the key of New World members of the genus (Hansson 2004) are included to integrate this new species. [ABSTRACT FROM AUTHOR]

Huanglongbing (HLB), a devastating citrus disease caused by Candidatus Liberibacter asiaticus, is efficiently vectored by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae). Tamarixia radiata (Waterston) plays a crucial role as an ectoparasitoid, preying on D. citri nymphs. By collecting and identifying headspace volatiles from fifth instar nymphs of D. citri using a gas chromatograph–mass spectrometer (GC–MS), we obtained a collection of 9 volatile compounds. These compounds were subsequently chosen to investigate the electrophysiological and behavioral responses of female T. radiata. At a concentration of 10 μg/μl, 9 compounds were compared with cis- 3-hexen-1-ol (control), resulting in trans- 2-nonenal inducing the highest relative electroantennogram (EAG) value, followed by hexanal, heptanal, n- heptadecane, tetradecanal, n- tetradecane, n- pentadecane, 1-tetradecanol, and 1-dodecanol. The top 5 EAG responses of female T. radiata to these compounds were further investigated through EAG dose–response experiments. The results showed positive dose–responses as concentrations increased from 0.01 to 10 μg/μl. In Y-tube olfactometer bioassays, female T. radiata exhibited a preference for specific compounds. They were significantly attracted to tetradecanal at a concentration of 10 µg/µl and trans- 2-nonenal at 0.01 µg/µl, while no significant attraction was observed toward hexanal, heptanal, or n- heptadecane. Our report is the first to demonstrate that volatiles produced by D. citri nymphs attract T. radiata , which suggests that this parasitoid may utilize nymph volatiles to locate its host. [ABSTRACT FROM AUTHOR]

Fall armyworm, Spodoptera frugiperda (J.E. Smith) is an invasive pest of agricultural crops including sweet corn and maize. The moth was first recorded in Australia in January 2020 and is now considered established in most states and territories, and research is underway to develop management strategies. Extensive rearing of S. frugiperda larvae and eggs occurred from March 2020 to April 2023 to understand the parasitoid complex present in Australia and identify potential biological control agents. We report here on the hymenopteran parasitoids reared during this period, which were identified using a combination of morphology and COI DNA barcoding, and provide images, a key to species, and contextual information to facilitate future research. Twelve species of parasitoids from five families of Hymenoptera are formally reported as parasitising S. frugiperda in Australia. Five species are here described as new: Chelonus patbat Fagan‐Jeffries, sp. nov. (Braconidae), Chelonus trojanus Fagan‐Jeffries, sp. nov. (Braconidae), Coccygidium mellosiheroine Atkin‐Zaldivar & Fagan‐Jeffries, sp. nov. (Braconidae), Coccygidium necatrix Atkin‐Zaldivar & Fagan‐Jeffries, sp. nov. (Braconidae), and Euplectrus frugiperdata Fagan‐Jeffries, sp. nov. (Eulophidae). [ABSTRACT FROM AUTHOR]

During the period 2019-2020, parasitoids of invasive oak lace bug (Corythucha arcuata) were studied in Bulgaria. Biological material (larvae of C. arcuata) was collected from European oak (Quercus robur) or Austrian oak (Quercus cerris) in five localities of the country. Five eulophid specimens (Hymenoptera: Eulophidae) were reared from the host larvae: Tamarixia pubescens, Elasmus sp., Minotetrastichus sp., Pnigalio sp. and Sympiesis sp. The impact of the parasitoids on the host number was very low (0.1-0.3%). The present records in Bulgaria are the first documented case of adaptation of native parasitoids to the host in the newly occupied areas in Europe and Asia. [ABSTRACT FROM AUTHOR]

The stinging nettle caterpillar, Oxyplax (syn. Darna) pallivitta (Lepidoptera: Limacodidae), is a serious invasive pest of agricultural products and a health hazard on the Hawaiian Islands first discovered in 2001. Nursery workers and homeowners have been stung by the caterpillars while handling their plants, especially rhapis palms (Rhapis sp.). Throughout its invaded range, it causes widespread damage, including the many cultivated and native palm species that have grown in Hawaii. Larvae contain urticating hairs that secrete a toxin, causing painful skin swelling and irritation on contact. Horticulture and nursery products impacted by the limacodid pest are estimated at $84.3 million (2018 value). Suppression efforts with pesticides and lure traps were ineffective, and the moth population continued to spread to major Hawaiian Islands (Hawaii, Kauai, Maui, Oahu). The introduction of specific biological control agents from the native region was thought to be the long-term solution for this invasive pest. Initial exploration in Indonesia and Thailand resulted in the introduction of a pupal ectoparasitoid, Nesolynx sp. (Hymenoptera: Eulophidae: Tetrastichinae), that was not specific. The oriental wasp, Aroplectrus dimerus Lin (Hymenoptera: Eulophidae: Eulophinae), idiobiont gregarious ectoparasitoid of the stinging nettle caterpillar, was introduced from Taiwan in 2004 for host specificity studies and biocontrol in Hawaii. Host range testing showed the parasitoid attacked only limacodid species, and it was approved for field release in 2010. The parasitoid identity, host specificity under containment facility conditions, reproductive performance, and colonization on the major infested sites were assessed. A total of 13,379 parasitoids were colonized on 162 release sites on four Hawaiian Islands. Evaluations were conducted using field surveys of larvae, pupal counts, and male lure traps. Field parasitism was thoroughly investigated on Oahu Island, averaging 18.9 ± 5.6% of 3923 collected larvae during 2010–2023. The numbers of male moths caught/trap/month were significantly reduced on Oahu Island (p < 0.05). Recently, the hyperparasitoid, Pediobius imbreus Walker (Hymenoptera: Eulophidae: Entedoninae), was detected, reducing the efficiency of A. dimerus in the field. The mean hyperparasitism of A. dimerus pupae was 27.3 ± 7.6% on Oahu Island. There was no detailed biological assessment for A. dimerus or its field evaluation available in scientific literature. Results were discussed regarding the potential use of A. dimerus in biocontrol elsewhere if the stinging nettle caterpillar was invaded in the future. [ABSTRACT FROM AUTHOR]

We report the results of investigations 2010 through 2023 of hymenopteran parasitoids associated with gall midges in Europe. A total of 242 collections of gall midges were made, from each of which one to several parasitoid species emerged, resulting in ca. 200 recorded parasitoid species and 267 host-parasitoid interaction records. The parasitoid families involved were Eulophidae (63 species), Platygastridae (56 species), Torymidae (34 species), Pteromalidae (31 species), Ceraphronidae (5 species), Eupelmidae (4 species), Eurytomidae (2 species) and Encyrtidae (1 species). As many as 159 interactions are reported for the first time, significantly enlarging our knowledge of gall midge - parasitoid interactions on the species level. Even more interesting, 51 host records are for parasitoid species for which no host was previously known. Similarly, 28 species of gall midge are reported as host to named parasitoids for the first time. Additionally, 91 parasitoid records were the first for the country in question. Differences between the rearing methods applied and their suitability for recording species with contrasting life histories, are discussed. [ABSTRACT FROM AUTHOR]

Background: This study evaluated the parasitizing efficiency of Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae) on the Galleria mellonella (Linnaeus) (Lepidoptera: Pyralidae) larvae and pupae. The sixth instar larvae and 48 h. old pupae were individually exposed for 24 h. to 15 newly emerged mated females of T. howardi. Following the emergence of parasitoids, observations were recorded on the percentage of parasitized and emergent pupae and larvae, life cycle duration, progeny, male and female emergence, sex ratio, longevity of male and female and adult per mg weight. Results: In both pupal and larval, parasitization and emergence were 100%. The pupa produced 438.56 progenies, with 394.76 females and 43.2 males and a sex ratio of 0.89. In larvae, 311.93 progenies emerged, with 259.83 females and 53.0 males and a sex ratio of 0.83. The T. howardi life cycle duration was 17.66 days in pupae and 20.13 days in larvae. Longevity of female and male progeny that emerged from pupae and larvae was 15.83, 13.40, and 10.40, 8.76 days respectively. The overall progeny production in pupae and larvae was 2.75 and 1.60 individuals per mg body weight, respectively. Conclusions: The highest parasitism as well as biological and reproductive development of T. howardi in G. mellonella pupae and larvae suggests that this host could be employed as an alternate host for mass multiplication. [ABSTRACT FROM AUTHOR]

Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) is the key parasitoid of the Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), in several citrus‐producing regions of the world. Chemical control is common to suppress ACP. Insecticides from globally used classes of insecticides for controlling ACP were tested on its primary parasitoid, T. radiata. Evaluations included dose–response of dimethoate, fenpropathrin, and imidacloprid in a topical application and lethal and sublethal effects from residues of imidacloprid, fenpropathrin, horticultural mineral oil (HMO), pyrethrin, and spirotetramat at 1, 3, and 7 days after application (DAA) of sprays on citrus trees in the orchard. The parasitism potential of the females that survived insecticide exposure was evaluated on untreated nymphs of ACP developing on citrus shoots and untreated parasitoid females were evaluated on nymphs treated with insecticides. In the topical application, imidacloprid was 8× more toxic to T. radiata than dimethoate and fenpropathrin. The lethal effect of the residues from imidacloprid and fenpropathrin sprays was more detrimental than other insecticides. Parasitoid mortality from 1‐ to 3‐day‐old residues averaged 90–96% for imidacloprid, 83–94% for fenpropathrin, 38–77% for pyrethrin, 43–44% for HMO, and 17–33% for spirotetramat. Parasitism by females that survived insecticide exposure was reduced by 71–88% from fenpropathrin, 28–59% from pyrethrin, 31–55% from imidacloprid, 44–4% from spirotetramat, and 39–11% from HMO compared to untreated females. The lethal and sublethal effects of all insecticides on T. radiata were significantly reduced at 7 DAA, suggesting a lower impact on its establishment and performance if releases are made after a week from spray application. [ABSTRACT FROM AUTHOR]

Females of host-feeding parasitic wasps often partition hosts of different stages for feeding and parasitization, but the underlying behavioral mechanisms are largely unknown, making it difficult to evaluate parasitoid–host interactions and their effects on biological control success. Tamarixia triozae (Burks) is an ectoparasitoid of tomato-potato psyllid Bactericera cockerelli (Šulc), which utilizes nymphs and kills them both by parasitization and host feeding. In this study, we exposed female wasps to 1st- to 5th-instar psyllid nymphs simultaneously and made 13-h continuous video recording of parasitoid–host interactions. We then quantified host stage-dependent handling time for feeding and oviposition and behaviors of parasitoid attacks and host defenses from encountering to successful feeding and oviposition. Female wasps were more likely to encounter and evaluate older hosts. However, the encounter and evaluation did not necessarily result in the success of feeding and oviposition. Our findings suggest that (i) T. triozae continues to assess the host using its ovipositor after the evaluation phase, (ii) females prefer the mid-aged hosts for feeding piercing and feeding and the later instars for oviposition probing and oviposition, (iii) the combination of stage-specific host nutrition value, integument thickness and defense behavior determines the success of feeding attacks, and (iv) the optimal host resource for parasitoid offspring fitness defines host stage selection for oviposition. This study contributes to our understanding of parasitoid–host interactions and mechanisms behind host stage selections. [ABSTRACT FROM AUTHOR]

The present study was carried out in Surman region kidney beans and broad beans were selected as summer and winter host plants during seasons 2020/2021. Correlation values between the population of Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) and mean temperature (°C) were recorded (0.81 and -0.27) in the summer and winter seasons, respectively. A negative correlation was calculated between the population of L. trifolii and relative humidity (RH.) in the summer season (-0.27) and a positive correlation occurred in the winter season recording (0.19). Correlation recorded between the population of Diglyphus isaea (Walker) Hymenoptera: Eulophidae) and mean temperature °C recorded (0.70 and -0.1) in the summer season and winter, respectively. On the other hand, correlation values were calculated (-0.17 and 0.36) between the population of D. isaea and (RH.) in the summer and winter seasons respectively. Positive correlations were recorded between the population of Opius pallipes (Wesmeal) (Hymenoptera: Braconidae) and mean temperature °C in summer and winter seasons with r values (0.61 and 0.035). Moreover, a negative correlation was calculated between the population of O. pallipes and (RH.) in the summer and winter seasons with r values (-0.30, and -.19), respectively. [ABSTRACT FROM AUTHOR]

Eulophidae and Pteromalidae are parasitic wasps with a global distribution and import for the biological control of pests. They can be distributed in different altitude regions, but their morphological and genetic adaptations to different altitudes are unclear. Here, we collected specimens that belong to Eulophidae and Pteromalidae from various altitudinal gradients, based on integrated taxonomic approaches to determine the species composition, and we analyzed their body shape and size from different altitudes using geometric morphometrics. Then, we performed an analysis of the D. isaea population’s haplotype genes to illustrate their genetic diversity. As a result, eight species that belong to two genera, Diglyphus Walker (Eulophidae) and Pachyneuron Walker (Pteromalidae), were identified, including two newly recorded species from China (D. chabrias and D. sabulosus). Through a geometric morphometrics analysis of body shape, we found that a narrow forewing shape and a widened thorax are the significant characteristics of adaptation to high-altitude environments in D. isaea and P. aphidis. Additionally, the body size studies showed a principal relationship between centroid size and altitude; the size of the forewings and thorax increases at higher altitudes. Next, using haplotype analysis, 32 haplotypes were found in seven geographic populations with high genetic diversity of this species. Our research provides preliminary evidence for the morphological and genetic diversity adaptation of parasitic wasps to extreme environments, and these data can provide important references for investigations on the ecological adaptability of parasitic wasps.

Euderomphalini Shafee, Rizvi and Khan (Hymenoptera: Eulophidae) is newly recognized from South Korea based on Euderomphale stomale Narendran and Hayat. The present study is to report the species as the first record in the country and to give a redescription along with the images of the diagnostic characteristics.

The African citrus psyllid Trioza erytreae (Del Guercio) (Hemiptera: Triozidae) is one of the most threatening pests for Mediterranean citriculture. It vectors the phloem-limited bacteria Candidatus liberibacter spp, the causal agent of huanglongbing (HLB), the most devastating citrus disease worldwide. Although HLB has yet to be recorded in Europe, T. erytreae has established in the Macaronesia Islands of Madeira (Portugal) and the Canary Islands (Spain), and in mainland Europe. In 2017, a classical biological control program was implemented, and Tamarixia dryi (Waterston) (Hymenoptera: Eulophidae) was released in an experimental citrus orchard in the Canarian Island of Tenerife in the spring of 2018. This study aimed to analyze i) the distribution and spatio-temporal dispersion of T. dryi, ii) the seasonal trend of T. erytreae and parasitism rates of T. dryi in the field and iii) the effect of T. dryi on T. erytreae population densities in the Canary Islands three consecutive years after the release of the parasitoid. Our results showed that T. dryi successfully established in the island of Tenerife and dispersed in four out of five surrounding islands where T. erytreae was present. Two years after the release of T. dryi, the proportion of sites infested by the psyllid decreased from more than 80% to less than 5% in the three main islands: Tenerife, La Palma, and Gran Canaria. Furthermore, the population density of T. erytreae was extremely low in the sites where it was present two and three years after the release of T. dryi. Parasitism rates remained higher than 40% throughout the sampling periods. Overall, our three-year study shows that the parasitoid T. dryi reduced and controlled the Candidatus liberibacter spp vector, the causal agent of HLB, T. erytreae in the Canary Islands.

Six species of Quadrastichus Girault (Eulophidae: Tetrastichinae) from China are reviewed, including three new species: Q. longiseta sp. nov., Q. flavomaculatus sp. nov., Q. longiscapus sp. nov. and one new country record, Q. vacuna (Walker, 1839). New distributional data for Q. anysis (Walker, 1839) and Q. sajoi (Szelényi, 1941), and a key to the Chinese species of Quadrastichus based on females, are included. [ABSTRACT FROM AUTHOR]

Simple Summary: The erythrina gall wasp, Quadrastichus erythrinae (Hymenoptera: Eulophidae), invaded Hawaii in April 2005 and rapidly dispersed throughout all the Hawaiian Islands in less than a year. Severe infestations devastated native and introduced trees of the genus Erythrina (Fabaceae), destroying thousands in the Western Pacific and Hawaii. Recently, this wasp has become a serious pest of Erythrina species around the world, including mainland USA, Mexico, and the Neotropical region. Expensive maintenance and chemical control measures have failed to contain this gall wasp and biocontrol was thought to be the only long-term solution. Exploratory trips in Tropical East Africa, South and West Africa, and Madagascar were undertaken during December 2005–June 2006 to determine the origin of this pest and survey its associated parasitoids as potential biocontrol agents. Tanzania was selected as a focal point of exploration because of the number of Erythrina species listed to be endemic to that country, more than anywhere else in Africa. Three hymenopteran ectoparasitoids were found in association with the galls, a eurytomid (Eurytoma sp.) and two eulophids (Aprostocetus spp.), whose larvae develop within the galls on immature stages of the gall former. Parasitoids from the Tanzanian and South African collections were amenable for insectary rearing on EGW from Hawaii. Host specificity and biology studies were conducted on the dominant parasitoid, Eurytoma erythrinae, in a containment facility in Hawaii. The parasitoid was found to be specific to EGW and was approved for release with good results in reducing the impact of the pest, saving the native Erythrina trees in Hawaii. We report on reproductive performance, rearing biology, host specificity testing, and the implication for biocontrol elsewhere with EGW problems. Eurytoma erythrinae Gates & Delvare (Hymenoptera: Eurytomidae) is an important biological control agent of the erythrina gall wasp (EGW), Quadrastichus erythrinae Kim (Hymenoptera: Eulophidae), an invasive species likely originating in eastern Africa that is a threat to Erythrina trees in Hawaii and worldwide. Thousands of Erythrina trees in Hawaii have succumbed to EGW since 2005 and died within a few years of infestation. The endemic wiliwili tree, Erythrina sandwicensis, an important component of Hawaii's dry forests and one of few deciduous native trees, were severely impacted by this wasp. Early during the invasion by EGW it became evident that the endemic species may be driven to extinction, and exploration programs for natural enemies of the EGW started in December 2005. East Africa was selected as the starting point for natural enemy exploration owing to high native Erythina species richness. Several gall formers were found in Tanzania and a putative color variant type of Q. erythrinae was detected in association with three ectoparasitoids. During January 2006, the dominant parasitoid of this gall former was introduced to Hawaii and described as the new species, E. erythrinae. It was found in Ghana and South Africa attacking other gall wasp species on Erythrina. Eurytoma erythrinae was a voracious ectoparasitoid feeding as a predator on 1–5 adjacent EGW immatures to complete its development. Host specificity studies that included seven nontarget gall-forming species showed no evidence of attraction or parasitism by this parasitoid. Mean ± SEM longevity of host-deprived females (40.4 ± 2.2 days) was significantly higher than males (20.5 ± 1.1 days). Host feeding enhanced longevity of ovipositing females (51.3 ± 1.5 days). Female E. erythrinae is synovigenic, with high egg-maturation rate. Peak fecundity (105–239 offspring/female), host feeding biology, short life cycle (18.4 ± 0.1 days), and synchronization with the host were additional desirable attributes of this species. The parasitoid was approved for field release in Hawaii in November 2008. A total of 3998 wasps were distributed on six Hawaiian Islands, with establishment in less than a year. Impacts on high density infestations of EGW were sufficient to prevent tree deaths. Limited rates of parasitism on low-density galled leaves, flowers, and seedpods necessitated the consideration for releasing a second parasitoid, Aprostocetus nitens Prinsloo & Kelly (Hymenoptera: Eulophidae). We report on the reproductive characteristics and host specificity of E. erythinae that could be of importance for classical biocontrol programs in areas with an EGW problem. [ABSTRACT FROM AUTHOR]

Through a survey that was conducted from 2020 to 2021, specimens were collected from wheat fields (Triticum aestivum L.) in West Azarbaijan province in the northwest of Iran using a sweep net. These are Neotrichoporoides nyemitawus (Rohwer, 1921), a new report for Iranian fauna and the West Palaearctic subregion. Illustrations of N. nyemitawus are provided, and its morphological characters are discussed. Neotrichoporoides Girault, 1913 in Iran, is represented by two species, N. szelenyii (Erdös, 1951) and N. viridimaculatus (Fullaway, 1955). Hereby, an identification key for Iranian species was provided. A worldwide distribution map of N. nyemitawus is also presented. Its role as the most important biocontrol agent of the shoot flies, Atherigona spp. (Diptera: Muscidae) was discussed. [ABSTRACT FROM AUTHOR]

Pteromalidae and Eulophidae are predominant and abundant taxa within Chalcidoidea (Hymenoptera: Apocrita). These taxa are found in diverse ecosystems, ranging from basin deserts (200 m) to alpine grasslands (4500 m). Mitochondria, cellular powerhouses responsible for energy production via oxidative phosphorylation, are sensitive to various environmental factors such as extreme cold, hypoxia, and intense ultraviolet radiation characteristic of alpine regions. Whether the molecular evolution of mitochondrial genes in these parasitoids corresponds to changes in the energy requirements and alpine environmental adaptations remains unknown. In this study, we performed a comparative analysis of mitochondrial protein-coding genes from 11 alpine species of Pteromalidae and Eulophidae, along with 18 lowland relatives, including 16 newly sequenced species. We further examined the codon usage preferences (RSCU, ENC-GC3s, neutrality, and PR2 bias plot) in these mitochondrial protein-coding sequences and conducted positive selection analysis based on their Bayesian phylogenetic relationships, and identified positive selection sites in the ATP6, ATP8, COX1, COX3, and CYTB genes, emphasizing the crucial role of mitochondrial gene adaptive evolution in the adaptation of Pteromalidae and Eulophidae to alpine environments. The phylogenetically independent contrast (PIC) analysis results verified the ω ratio of 13 PCGs from Pteromalidae and Eulophidae increased with elevation, and results from generalized linear model confirm that ATP6, ATP8, COX3, and ND1 are closely correlated with temperature-related environmental factors. This research not only enriched the molecular data of endemic alpine species but also underscores the significance of mitochondrial genes in facilitating the adaptation of these minor parasitoids to plateau habitats. [ABSTRACT FROM AUTHOR]

Several species of ambrosia beetles in the genera Euwallacea, Xyleborus, and Xylosandrus (Coleoptera: Curculionidae: Scolytinae) are considered major pests in agriculture, forestry and urban areas. Their concealed lifestyle allows them to evade detection, and increases their chances of being introduced to non-native regions. Their reproduction is dominated by sibling mating within maternal galleries, and this behaviour makes them difficult to control. Although a handful of studies have identified natural enemies associated with ambrosia beetles, very few have done this with the goal of creating a classical biological control programme. In this study, we sought to identify hymenopteran parasitoids associated with the invasive Euwallacea fornicatus species complex. We collected branches from infested trees in a native region in Taiwan, recorded parasitoid emergence, and attempted to rear any emerging parasitoids using laboratory reared hosts and experimentally infested logs. We identified three species of parasitoid wasps that successfully parasitised beetles in the E. fornicatus species complex. These species were all new to science belonging to the genera Eucosmophorus (Braconidae), Phymastichus (Eulophidae), and Plastanoxus (Bethylidae). [ABSTRACT FROM AUTHOR]

The carrot psyllid, Bactericera trigonica, is a vector of 'Candidatus Liberibacter solanacearum' which infects carrots and many of solanaceous plants. The psyllid was first reported in Spain, then it was rapidly spreading throughout the Mediterranean countries, where it causes considerable damages to carrot crops. To minimize the spread of psyllid species as well as the associated fastidious bacteria, field inspections have been carried out in order to seek for a natural enemies of B. trigonica. Field surveys revealed the presence of a new eulophid parasitoid for the first time in Tunisia attacking larvae of B. trigonica, the main responsible for the significant losses in carrot fields. In order to study the parasitism rate of this parasitoid, a weekly sampling of carrot plants carrying the psyllids and its parasitoids was performed in carrot fields. The parasitism rate and the preferential stage for this parasitoid were also determined under laboratory conditions. The result shows Tamarixia pronomus, preferred late (4th and 5th) instar larvae to early (2nd and 3rd) instar larvae of B. trigonica. There, the parasitism average of late instars was estimated to average 80% and approached 100%. It should be noted that parasitism rates varied by season, with the spring showing the highest averages. Further efforts are warranted to enhance the biological control of B. trigonica and thereby reduce psyllid populations and the spread of 'Candidatus Liberibacter solanacearum'. [ABSTRACT FROM AUTHOR]

Beneficial ladybird beetles are parasitized by several species of parasitoid wasps and flies. Samples of ladybirds from Western Iran including Lorestan, Khuzestan and Kurdistan provinces revealed the presence of the parasitoid Oomyzus scaposus (Thomson, 1878). Adult wasps emerged from larvae and pupae of the ladybird Coccinella septempunctata L. (Coleoptera: Coccinellidae). The identity of the wasp was determined by its morphology and confirmed by sequences of cytochrome oxidase, subunit I. A comparison of these DNA barcodes from other species of Oomyzus and other populations of O. scaposus showed a close relationship to the Russian population. Morphological characters are documented by scanning electron microscope images. [ABSTRACT FROM AUTHOR]

Simple Summary: Hyphantria cunea (Drury) (Lepidoptera: Erebidae), also known as the fall webworm, is a worldwide quarantine pest. In recent years, it has spread and caused serious damage in China. Tetrastichus septentrionalis Yang is a native dominant parasitic natural enemy population found in China that has potential application value for biological control. We selected Tenebrio molitor as an alternative host for artificially rearing T. septentrionalis via screening. We found that diapause in T. septentrionalis is of the long-day type, and can also be used in insect enemy mass production. This study's findings may allow the preservation period of this species to be prolonged by utilizing the phenomenon of diapause in the future and provide a reference for the biological control of the fall webworm and other leaf-eating pests. The chalcid wasp Tetrastichus septentrionalis Yang (Hymenoptera: Eulophidae) is one of the dominant pupal parasitoids of Hyphantria cunea (Drury) (Lepidoptera: Erebidae). In this study, the photoperiod's effect on diapause induction in T. septentrionalis using the alternative host Tenebrio molitor was measured, revealing that T. septentrionalis is of the long-day type. The critical photoperiods for diapause induction in T. septentrionalis were estimated to be between photoperiods of 13:11 and 14:10 (L:D) h at 18 °C, and between photoperiods of 12:12 and 13:11 (L:D) h at 21 °C and 24 °C. We also found that T. septentrionalis diapausing larvae were grey-brown, while normally developed (non-diapausing) individuals were light yellow. The diapause-sensitive insect state was the larval stage, and the short light exposure treatment had a significant cumulative effect on diapause induction. The least squares method was used to calculate a lower developmental threshold of 13.34 ± 0.50 °C and an effective cumulative temperature of 184.46 ± 11.46 d·°C for post-diapause development. The average supercooling point of diapausing mature larvae was significantly lower than that of non-diapausing ones. Our research on T. septentrionalis provides a reference for the biological control of H. cunea and other leaf-eating pests. [ABSTRACT FROM AUTHOR]

Eulophid larvae discovered in galleries of Agrilus cuprescens (Ménétries, 1832) within canes of Rubus sp. (Rosaceae) in the Pacific Northwest, U.S.A. region between 2018 and 2021 were identified as Baryscapus rugglesi (Rohwer, 1919) (subfamily Tetrastichinae). This species had previously only been found in eastern North America. Identification was based on numerous specimens reared from larvae collected from eight disparate locations in western Oregon and Washington State, U.S.A., in 2019 and 2021, and examination against its type series from 1919 in Minnesota, U.S.A. and specimens from 1938 in New York, U.S.A (Mundinger 1941). Both sexes of B. rugglesi are herein redescribed and illustrated. Additionally, DNA sequences from specimens collected in 2019 were direct sequence matches with original specimens collected in 2018. The ubiquitous occurrence of B. rugglesi suggests it is likely a predominant parasitoid of A. cuprescens in the region. Baryscapus rugglesi is a gregarious larval parasitoid of several native Agrilus spp. in North America, so it is presumably native to the Nearctic region and has adapted as an alternative parasitoid of A. cuprescens, a Eurasian-native pest introduced into North America. However, COI sequences of B. rugglesi were similar to those of an unidentified eulophid from Europe in the Barcode of Life Database (almost 96% identity), possibly indicating a Holarctic distribution. Observed wasp biology, behavior, and perspectives on the potential role of B. rugglesi as a natural enemy within integrated pest management programs for A. cuprescens control are discussed. [ABSTRACT FROM AUTHOR]

Leptocybe invasa Fisher & La Salle, 2004 (Hymenoptera: Eulophidae), is a gall wasp that infests Eucalyptus L'Hér. (Myrtaceae) species and their crosses in nurseries, orchards and plantations. This pest infests the young plants, coppice shoots and both middle aged and old trees in an ever-increasing number of countries around the world; making it important to record new countries with incidences, as well as new host plants and associated parasitoids of this pest. The objectives of this paper were to record, for the first time, L. invasa galls parasitized by Megastigmus sp. (Hymenoptera: Torymidae) on a new host plant, Eucalyptus brassiana S.T. Blake in Indonesia and key biological data from this association. The number of galls was similar between branch parts (petioles, midribs and stems) and branches. The number of emerged adults differed between their species (L. invasa and Megastigmus sp.) with a higher number for the pest, but similar between branches. The occurrence of L. invasa in Indonesia is alarming as this country is a large producer of paper, pulp and viscose materials from Eucalyptus wood for local and foreign markets. However, its parasitism by Megastigmus opens the possibility to develop biological control programs. [ABSTRACT FROM AUTHOR]

We report the results of DNA barcoding week-long Malaise trap catches from 11 sites in three Thai conservation areas, concentrating on the parasitoid Hymenoptera, particularly the superfamily Ichneumonoidea. From a total of 15,338 parasitoid wasp sequences, 13,473 were barcode compliant and could be assigned to a family based on morphology and sequence data. These collectively represented 4917 unique BINs (putative species) in 46 families, with the Scelionidae, Ichneumonidae, Eulophidae, Braconidae and Platygastridae being, by far, the most abundant. Spatial proximity had a strong positive effect on the numbers of BINs shared between traps. [ABSTRACT FROM AUTHOR]

Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae) and Palmistichus elaeisis (Delvare & LaSalle) (Hymenoptera: Eulophidae) are commercially used in the biological control of defoliating lepidopterans in Brazil. The combination of these natural enemies in integrated pest management systems and the risks of intraguild interactions in simultaneous releases were evaluated in the laboratory. The objective was to verify the possible biological effects of intraguild interaction between P. nigrispinus and P. elaeisis. Pupae of natural host Thyrinteina arnobia (Stoll) (Lepidoptera: Geometridae) and of the alternative host Tenebrio molitor L. (Coleoptera: Tenebrionidae), aged 24 hours, were individualized and exposed to parasitism by females of P. elaeisis for 24 hours. The selectivity of P. nigrispinus to parasitized prey was tested with T. arnobia, T. molitor and with volatile compounds extracted from pupae parasitized or healthy. The biomass of T. molitor pupae, healthy or parasitized by P. elaeisis (at one, nine or 18 days), consumed by P. nigrispinus was calculated. The selectivity of each P. nigrispinus female for healthy or parasitized pupae was observed and the effect on the biology of the predator was analysed. Podisus nigrispinus preferred healthy prey to those with more than one day of parasitism and was attracted to pupae washed with hexane extract from healthy hosts. The body mass of this predator was higher when feeding on healthy pupae. The intraguild interaction between P. nigrispinus and P. elaeisis is symmetrical, indicating that these natural enemies can be used, simultaneously, in the integrated management of defoliating caterpillars without reducing their efficiency. [ABSTRACT FROM AUTHOR]

Simple Summary: This study compared the differences in symbiotic bacteria between the A and B lineages of the Leptocybe invasa, so as to provide a reference for the scientific control of the pest. (1) Background: Leptocybe invasa (Hymenoptera: Eulophidae) is a global invasive pest that seriously damages eucalyptus plants and has caused serious harm to forestry production in many countries. Two genotypically distinct lineages of L. invasa have been detected outside of Australia, namely, lineage A and lineage B. However, the composition and abundance of endosymbiotic bacteria in L. invasa are still unclear between lineages. Therefore, the purpose of this study was to compare the bacterial communities in female adults of L. invasa of different lineages distributed in the same domain; (2) Methods: The PacBio Sequel II platform was used to compare bacterial community composition between lineages of L. invasa by sequencing the V1–V9 region of the 16S rRNA gene, and fluorescence quantitative PCR was used to compare the relative expression of Rickettsia between lineages of L. invasa; (3) Results: A total of 437 operational taxonomic units (OTUs) were obtained. These OTUs were subdivided into 20 phyla, 32 classes, 77 orders, 129 families, and 217 genera. At the genus level, the dominant bacteria in lineage A and lineage B were Rickettsia and Bacteroides, respectively. There were differences in the bacterial community of L. invasa between lineages, and the abundance and relative expression of Rickettsia in lineage A were significantly higher than those in lineage B; (4) Conclusions: There were differences in the bacterial community of L. invasa between lineages, and the abundance and relative expression of Rickettsia in lineage A were significantly higher than those in lineage B. [ABSTRACT FROM AUTHOR]

Background: The coconut black-headed caterpillar, Opisina arenosella Walker (Lepidoptera: Xyloryctidae) has been a serious defoliator of coconut plants in many coconut producing countries including Vietnam. Trichospilus pupivorus Ferrière (Hymenoptera: Eulophidae) is pupal endo-parasitoid of O. arenosella with high percent parasitism and abundance in the coconut fields and appears to be a good biological control agent against the coconut black-headed caterpillar in Vietnam. The objective of this study was to investigate the developmental biology of T. pupivorus on O. arenosella. Methods: The experiment was carried out at the Faculty of Agronomy, Nong Lam University, Viet Nam during 2020 and 2021. The developmental biology of T. pupivorus on O. arenosella was studied in the laboratory at a constant temperature of 28°C and a photoperiod of 12L: 8D. Result: Total developmental time from egg to adult emergence was 14.0 days. The females laid a mean of 124.2 eggs during an average lifespan of 9.4 days. The number of progenies emergence from a single pupa of O. arenosella was 103.8. The offspring sex ratio was female-biased (8.0%). The results would contribute to the knowledge of the biology of this parasitoid to optimize a mass rearing system for a biological control program against O. arenosella. [ABSTRACT FROM AUTHOR]

The Turkestan cockroach, Blatta lateralis (Walker), is a peridomestic pest of growing concern in the US Southwest. The parasitoid Aprostocetus hagenowii (Ratzburg) is used in IPM programs targeting other blattid cockroach species and may aid in B. lateralis suppression. Information about the ability of A. hagenowii to parasitize B. lateralis is lacking. A no-choice host-switching experiment was used to test A. hagenowii acceptance of B. lateralis oothecae, and a multigenerational no-choice experiment was used to determine the suitability of B. lateralis as a host for A. hagenowii over several months of rearing. Periplaneta americana (L.) (Blattodea: Blattidae), the preferred host of A. hagenowii, and Blatta orientalis L., a known host and relative of B. lateralis, were used for comparison. Development time was similar among hosts and generations (P > 0.05). Parasitism success and proportion of female progeny declined significantly with subsequent generations on both Blatta spp. (parasitism success: χ2 = 14.916; df = 2; P = 0.001; proportion female: H = 6.364; df = 2; P = 0.041). These results suggest that A. hagenowii may initially aid in suppression of B. lateralis, but an overall decline in fitness will require repeated releases or provisioning of P. americana oothecae. Development of a strain more suitable for B. lateralis control may be possible via selection from laboratory strains or through use of wild A. hagenowii from areas where B. lateralis is present. [ABSTRACT FROM AUTHOR]

Chouioia cunea Yang 1989 is a parasitic wasp of many lepidopteran insects during their pupal stage, and has been successfully used to control pests such as the fall webworm Hyphantria cunea. Here we reported the chromosome-level genome of C. cunea by using short (MGI-SEQ), long (Oxford Nanopore), chromatin-linked (Hi-C) sequencing reads and transcriptomic data, representing the first chromosome-level genome of parasitic wasps of the family Eulophidae. The total assembly length is 171.99 Mb, containing 6 pesudo-chromosomes with a GC content of 36.89% and the scaffold/contig N50 length of 31.70/26.52 Mb. The BUSCO completeness of the assembly was estimated to be 98.7%. A total of 12,258 protein-coding genes (PCGs), 10,547 3′-UTRs, and 10,671 5′-UTRs were annotated. This high-quality genome is an important step toward a better understanding of the genomes of the Eulophidae (Chalcidoidea), and will serve as a valuable resource for analyses of phylogenetic relationships and the evolution of Hymenoptera. [ABSTRACT FROM AUTHOR]

In this paper, a new species of Entedon Dalman, E. flavifemur sp. nov. is described from Tibet and three species, E. albifemur Kamijo, E. crassiscapus Erdös, and E. nomizonis Kamijo are reported from China for the first time. A detailed description and illustrations of the new species are provided, as well as diagnoses and illustrations of the three newly recorded species. [ABSTRACT FROM AUTHOR]

Megachile rotundata F. is the primary commercial pollinator for alfalfa seed production in North America. Managed M. rotundata populations are susceptible to several mortality factors including attack by parasitoids. One such parasitoid, Melittobia acasta Walker, is a multivoltine wasp whose infestations can decimate bee stocks. Details of M. acasta life history using M. rotundata as a host are needed to develop control strategies. Our objectives were (i) to describe the M. acasta life cycle using M. rotundata prepupae as hosts and (ii) to determine the M. acasta developmental base temperature and propose a degree-day model. First, 150–300 M. acasta adults were introduced to 60 M. rotundata prepupae (10–20 wasp females/4 bee prepupae) upon which they oviposited. Progeny development (at 30 °C) was monitored through adulthood. We identified 12 distinct phases of the M. acasta life cycle that were observed among samples over an average of 19.5 days. Second, vials each containing a M. rotundata prepupa with M. acasta eggs were positioned across a temperature gradient bar (2 vials per temperature). In repeated trials, wasp development was tracked from egg to adult where a mean development time for 30 °C was found to be 13 days. A linear regression analysis determined the lower developmental temperature threshold to be 8.55 °C. Application of this base temperature in a degree-day model revealed an average of 305.8-degree-day accumulation from egg to adult. These results provide a framework to assist bee managers in devising M. acasta control strategies and timing their implementation. [ABSTRACT FROM AUTHOR]

Laboratory investigations were undertaken at the Department of Studies in Sericulture Science, University of Mysore, Manasagangotri, Mysuru, to understand the effects of host species and host age on the reproductive performance and morphometric characteristics of progenies of an indigenous endo-pupal parasitoid, Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae). The parasitoid developmental durations were significantly longer in younger pupae of S. litura and older pupae of S. frugiperda. The mean values for progeny production were superior when the parasitoid developed in younger host when compared with older host of both the species. The longevity values for the progeny females did not differ when developed in pupae of both the ages of the hosts. Regarding morphometric parameters of the progeny males and females resulted from either age of hosts of both the species, the values were significantly superior fora greater number of parameters with younger hosts of S. frugiperda when compared with those with younger hosts of S. litura where the parameters have been shared by either category of hosts in terms of their superiority. [ABSTRACT FROM AUTHOR]

Diplolepis ogawai Abe and Ide sp. nov. (Hymenoptera: Cynipidae) induces galls on Rosa hirtula (Regel) Nakai (Rosales: Rosaceae), which is endemic to a restricted area of Honshu, the main island of Japan. The gall is induced mainly on the leaf of R. hirtula in spring and the mature gall falls to the ground in early summer. The gall-inducing wasp emerges from the gall on the ground in the following spring, suggesting that D. ogawai is univoltine. From spring to summer, the braconid Syntomernus flavus Samartsev and Ku and the eulophid Aprostocetus sp. are parasitic on the larva of D. ogawai in the gall, and the adult wasp of both parasitoid species emerges from the gall on the ground in summer. For S. flavus , this is the first distribution record in Japan and the first host record. Since R. hirtula is threatened with extinction by succession and deforestation, D. ogawai and its two parasitoid wasp species are considered to be at risk of coextinction with the threatened rose. In the event that the population size of this rose species is further reduced, D. ogawai and its parasitoids may -become extinct prior to the extinction of R. hirtula. To conserve these three wasp species associated with R. hirtula , protection of remnant vegetation where individuals of this threatened rose species grow is necessary. [ABSTRACT FROM AUTHOR]

Simple Summary: In gene expression investigations, the first crucial step is choosing appropriate housekeeping genes. However, the choice of reference genes is not absolute but relative and varies with different experimental conditions. It is vital to note that using unvalidated or unscreened internal reference genes can lead to erroneous inferences. This study was conducted on Leptocybe invasa to calculate the stability of eight housekeeping genes across various test conditions, such as sexes, somites, temperatures, diets, and pesticides. The relative expression of HSP90 at different temperature settings was evaluated to validate the results. This study aims to assist future gene expression research on this invasive species and lay the groundwork for further investigations into the gene function of this pest. Leptocybe invasa (Hymenoptera: Eulophidae) is a globally intrusive pest. Despite extensive research into the physiological responses of this pest, our understanding of the molecular mechanisms still needs to be improved. We want to accurately investigate the expression of L. invasa's target genes, so it is imperative to select fitting reference genes. In this study, eight housekeeping genes' stability (RPS30, ACTR, 18S rRNA, ACT, RPL18, GAPDH, 28S rRNA, and TUB) was tested under five different experimental conditions, including male or female adults, somites (head, thorax, and abdomen), temperatures (0 °C, 25 °C, and 40 °C), diets (starvation, clear water, 10% honey water, Eucalyptus sap), and pesticides (acetone was used as a control, imidacloprid, monosultap). Gene stability was calculated using RefFinder, which integrates four algorithms (the ∆Ct method, geNorm, NormFinder, and BestKeeper). The findings implied that ACT and ACTR were the most accurate when comparing sexes. For analyzing different somites, 28S rRNA and RPL18 were ideal; the 28S rRNA and RRS30 were perfect for analyzing at different temperatures. The combination of ACT and GAPDH helped to analyze gene expression in different diets, and GAPDH and 28S rRNA were suitable for various pesticide conditions. Overall, this research offers a complete list of reference genes from L. invasa for precise analysis of target gene expression, which can improve the trustworthiness of RT-qPCR and lay the foundation for further investigations into the gene function of this pest. [ABSTRACT FROM AUTHOR]

Melittobia acasta Walker is one among other hymenopterous parasitoids of Megachile rotundata F. Commercial M. rotundata populations are employed to pollinate North American alfalfa for seed production. This wasp can be prolific when using M. rotundata as a host and can reduce or destroy bee stocks. Hundreds of M. acasta female offspring can develop in a single M. rotundata cell and disperse to infest other cells, producing thousands of more parasitoids. In this study, we determined (i) upon what bee life stages M. acasta females choose to lay eggs and if those eggs ultimately become adults and (ii) M. acasta female longevity when exposed to various resources within M. rotundata cells. We found that M. acasta females lay eggs on M. rotundata prepupae and pupae and that those eggs can hatch and survive to adulthood. Eggs are not laid on early instar bee larvae; eggs laid on adults do not survive. Average female life span is 5 days without feeding, 8–9 days if a pollen–nectar provision is available while the bee develops through larval stages, and 34 days if the wasp can feed on prepupal hemolymph. Wasp females can emerge from bee cells several days after trays of cells are taken to fields. Therefore, adult females could survive long enough for new bee offspring to become prepupae. Our findings support a better understanding of host life stage preference and the longevity of M. acasta females that can inform the timing of the implementation of possible control measures. [ABSTRACT FROM AUTHOR]

The wheat sheath miner, Cerodontha australis, is widespread and abundant in New Zealand and also occurs in eastern Australia. Adult and larval C. australis feed on cereals and grasses, including the economically important perennial ryegrass, Lolium perenne. There is little literature about C. australis, and much of the early work may relate to other species due to its initial misidentification. Morphologybased identification can be challenging, and the absence of online barcode sequences from voucher specimens for C. australis has precluded diagnosis using molecular techniques. In this study, two individual adult leafminers collected from L. perenne plants in New Zealand were confirmed as C. australis morphologically. One has been retained as a voucher specimen and its mitochondrial barcode sequence submitted to online databases. Comparison with adult and larval specimens previously sequenced by the authors confirmed they were also C. australis. Molecular identification of 20 hymenopteran pupal endoparasitoids, and a subset of the puparia they emerged from, revealed Trichopria sp. (Diapriidae), Eupelmus messene (Eupelmidae) and three haplotypes (or closely related species) of Eulophidae. Sequences for all wasps were submitted to GenBank. All the puparia were visually identified as C. australis, and a subset that included a host pupa of each identified endoparasitoid species were confirmed as C. australis based on comparison with our barcode sequence. This work will aid future studies on C. australis and has allowed identification of unidentified sequences on public databases formerly submitted by other New Zealand researchers. It also provides new records of association between C. australis and its pupal endoparasitoids. More broadly, our study provides an example of the importance of authoritative morphological identification of specimens alongside molecular identification, and highlights the challenges in identifying species for which this has not been done. [ABSTRACT FROM AUTHOR]

The pea leafminer, Chromatomyia horticola (Goureau) (Diptera: Agromyzidae) is a polyphagous and serious pest of peas. In India, this pest is attacked by many parasitoids and among them Diglyphus horticola Khan (Hymenoptera: Eulophidae) is an important one, however, demographics and pest-kill potential of this parasitoid has not been studied so far. This study presents the first report on its demographics and pest-kill potential on C. horticola. The parasitoid showed three modes of host-killing behaviour viz. host-feeding, parasitism and host-stinging. The parasitoid females killed more number of hosts by parasitism than host-feeding or host-stinging. The pre-adult survival, net reproductive rate, intrinsic rate of increase (rm) and finite rate of increase (λ) were higher on the 5-days old host larvae than those reared on the 3-days old larvae. Demographics and pest-kill parameters of D. horticola were also better on 5-days old host larvae than on 3-days old host larvae. Based on the study, D. horticola appeared to be a promising biocontrol agent for the suppression of C. horticola in peas and could be promoted through conservation biological control. Further studies are required to standardize the mass production protocol and release rates to use the parasitoid by augmentation. [ABSTRACT FROM AUTHOR]