A synopsis of the genus Cylindrostethus Fieber 1861 (Insecta: Hemiptera: Gerridae).

Cylindrostethus Fieber, 1861 is one of the most striking genera of water striders (Insecta: Hemiptera: Gerridae) and has Pantropical distribution. Members of this group can be recognized by the very long, cylindrical body; the short antennomere IV; the short labium not reaching the mesosternum; and by characteristics of the abdomen of males and females. Although Neotropical representatives of the genus have been revised, there are pending taxonomic issues related to this fauna, and that of the Eastern Hemisphere has been barely studied in recent years. Here, we present a short note about the authorship of Cylindrostethus, an updated key to all species of the genus, a new synonymy, and the description of a previously unknown macropterous male of C. hungerfordi Drake and Harris.

Identification and expression patterns of somatic piRNAs and PIWI genes in Riptortus pedestris (Hemiptera: Alydidae).

RNA interference (RNAi)-based gene silencing is a feasible and sustainable technology for the management of hemipteran pests by double-stranded RNA involvement, including small-interfering RNA, microRNA, and Piwi-interacting RNA (piRNA) pathways, that may help to decrease the usage of chemical insecticides. However, only a few data are available on the somatic piRNAs and their biogenesis genes in Riptortus pedestris, which serves as a significant pest of soybean (Glycine max). In this study, two family members of the PIWI gene were identified and characterized in R. pedestris, containing Argonaute3 (RpAgo3) and Aubergine (RpAub) genes with conserved protein domains, and their clusters were validated by phylogenetic analysis. In addition, they were widely expressed in all developmental stages of the whole body of R. pedestris and had lower expression levels in R. pedestris guts under different rearing conditions based on previous transcriptome sequencing. Furthermore, abundant clean reads were filtered to a total number of 45,998 piRNAs with uridine bias at the first nucleotide (nt) position and 26-32 nt in length by mapping onto the reference genome of R. pedestris according to our previous whole-transcriptome sequencing. Finally, our data revealed that gut bacterial changes were significantly positively or negatively associated with differentially expressed piRNAs among the five comparison groups with Pearson correlation analysis. In conclusion, these findings paved new avenues for the application of RNAi-based biopesticides for broad-spectrum hemipteran pest control.

Elucidating the ecophysiology of soybean pod-sucking stinkbug Riptortus pedestris (Hemiptera: Alydidae) based on de novo genome assembly and transcriptome analysis.

Food security is important for the ever-growing global population. Soybean, Glycine max (L.) Merr., is cultivated worldwide providing a key source of food, protein and oil. Hence, it is imperative to maintain or to increase its yield under different conditions including challenges caused by abiotic and biotic stresses. In recent years, the soybean pod-sucking stinkbug Riptortus pedestris has emerged as an important agricultural insect pest in East, South and Southeast Asia. Here, we present a genomics resource for R. pedestris including its genome assembly, messenger RNA (mRNA) and microRNA (miRNA) transcriptomes at different developmental stages and from different organs. As insect hormone biosynthesis genes (genes involved in metamorphosis) and their regulators such as miRNAs are potential targets for pest control, we analyzed the sesquiterpenoid (juvenile) and ecdysteroid (molting) hormone biosynthesis pathway genes including their miRNAs and relevant neuropeptides. Temporal gene expression changes of these insect hormone biosynthesis pathways were observed at different developmental stages. Similarly, a diet-specific response in gene expression was also observed in both head and salivary glands. Furthermore, we observed that microRNAs (bantam, miR-14, miR-316, and miR-263) of R. pedestris fed with different types of soybeans were differentially expressed in the salivary glands indicating a diet-specific response. Interestingly, the opposite arms of miR-281 (-5p and -3p), a miRNA involved in regulating development, were predicted to target Hmgs genes of R. pedestris and soybean, respectively. These observations among others highlight stinkbug's responses as a function of its interaction with soybean. In brief, the results of this study not only present salient findings that could be of potential use in pest management and mitigation but also provide an invaluable resource for R. pedestris as an insect model to facilitate studies on plant-pest interactions.

Silicon applications in rice plants alter the stylet probing behaviors of Glyphepomis spinosa (Hemiptera: Pentatomidae).

The stink bug Glyphepomis spinosa Campos & Grazia (Hemiptera: Pentatomidae) is a potential rice pest in Brazil. This study evaluates the interaction between silicon sources and 3 rice cultivars (BRS Esmeralda, Canela de Ferro, and IRGA 417) and examines how increasing silicon levels affect the stylet probing behavior of G. spinosa. The experiment was set up in a completely randomized design with a 3 × 3 factorial scheme (silicon sources: calcium silicate, potassium silicate, a control, and 3 rice cultivars). Fertilizing rice plants with Si altered the probing behavior of the stink bug G. spinosa. The cultivar interaction by Si source was significant in a few variables. This was evidenced by longer periods without ingestion, prolonged time to the first stylet probe (initial probing), and less time spent in cellular maceration. This result supports the use of electropenetrography as a tool to evaluate resistance inducers in plants.

Different binding properties of odorant-binding protein 8 to insecticides in Orius sauteri.

Chemical sensing systems are vital in the growth and development of insects. Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important natural enemy of many pests. The molecular mechanism of odorant binding proteins (OBPs) binding with common insecticides is still unknow in O. sauteri. In this study, we expressed in vitro OsauOBP8 and conducted fluorescence competition binding assay to investigate the function of OsauOBP8 to insecticides. The results showed that OsauOBP8 could bind with four common insecticides (phoxim, fenitrothion, chlorpyrifos, deltamethrin). Subsequently, we used molecular docking to predict and obtained candidate six amino acid residues (K4, K6, K13, R31, K49, K55) and then mutated. The result showed that three key residues (K4, K6, R31) play important role in OsauOBP8 bound to insecticides. Our study identified the key binding sites of OsauOBP8 to insecticides and help to better understand the molecular mechanism of OBPs to insecticides in O. sauteri.

Effects of photoperiod and temperature on the developmental duration and diapause in Dolycoris baccarum (Heteroptera: Pentatomidae) from Hohhot, Inner Mongolia, China.

The shield bug, Dolycoris baccarum (L.) (Heteroptera: Pentatomidae), is widely distributed across Asia and Europe. At high latitudes, it overwinters, as adult in diapause, which then becomes the insect source for the following year. To fully understand the developmental duration and diapause characteristics of D. baccarum, the effects of photoperiod and temperature were studied in a population from Hohhot, Inner Mongolia, China. The results indicated that the developmental duration was significantly prolonged at temperatures of 20 or 25 °C, with a prolonged light period; however, when the light period was prolonged to 16L:8D and 18L:6D, the developmental duration was shortened significantly. Furthermore, the developmental duration was also shortened significantly with increasing temperature, when the photoperiod was 12L:12D for short days and 16L:8D for long days. All individuals entered diapause under short-day conditions of 10L:14D and 12L:12D at a temperature of 20 °C; however, the diapause rate decreased significantly under 14L:10D and 16L:8D photoperiods, and the diapause rate decreased significantly at a temperature of 25 °C with prolonged photoperiod. Interestingly, when the photoperiod was fixed at 12L:12D, the diapause rates at different temperatures (20, 25, 28, and 30 °C) exceeded 95%; while the effect of temperature on diapauses was nonsignificant under this photoperiod, it was still sensitive to the photoperiod; at a photoperiod of 16L:8D, the effect of temperature on the diapause rate was noticeable, and the diapause rate decreased significantly with increasing temperature.

Nanoparticle-delivered RNAi-based pesticide target screening for the rice pest white-backed planthopper and risk assessment for a natural predator.

Vacuolar-type (H+)-ATPase (vATPase) is a conserved multi-subunit eukaryotic enzyme composed of 14 subunits that form a functional complex consisting of an ATP-hydrolytic domain (V1) and a proton-translocation domain (V0). ATP hydrolysis and subsequent H+ translocation rely heavily on a fully assembled V1/V0 complex. Since vATPase is crucial for insect survival, it is a viable molecular target for pest control. However, detailed functional analyses of the 14 subunits and their suitability for pest control have not been fully explored in a single insect species. In this study, we identified 22 vATPase subunit transcripts that correspond to 13 subunits (A1, A2, B, C, D, E, F, G, H, a1, a2, c and d) in the white-backed planthopper (WBPH), Sogatella furcifera, a major hemipteran pest of rice. RNAi screens using microinjection and spray-based methods revealed that the SfVHA-F, SfVHA-a2 and SfVHA-c2 subunits are critical. Furthermore, star polymer (SPc) nanoparticles were utilized to conduct spray-induced and nanoparticle-delivered gene silencing (SI-NDGS) to evaluate the pest control efficacy of RNAi targeting the SfVHA-F, SfVHA-a2 and SfVHA-c2 transcripts. Target mRNA levels and vATPase enzymatic activity were both reduced. Honeydew excreta was likewise reduced in WBPH treated with dsRNAs targeting SfVHA-F, SfVHA-a2 and SfVHA-c2. To assess the environmental safety of the nanoparticle-wrapped dsRNAs, Cyrtorhinus lividipennis Reuter, a major natural enemy of planthoppers, was also sprayed with dsRNAs targeting SfVHA-F, SfVHA-a2 and SfVHA-c2. Post-spray effects of dsSfVHA-a2 and dsSfVHA-c2 on C. lividipennis were innocuous. This study identifies SfVHA-a2 and SfVHA-c2 as promising targets for biorational control of WBPH and lays the foundation for developing environment-friendly RNAi biopesticides.

Describe the morphology and mitochondrial genome of Mecidea indica Dallas, 1851 (Hemiptera, Pentatomidae), with its phylogenetic position.

We here describe the external morphology and complete mitochondrial genome characteristics of Mecidea indica Dallas, 1851, and clarify the evolutionary rate and divergence time. The M. indica mitochondrial genome length is 15,670 bp, and it exhibits a typical high A+T-skew (76.31%). The sequence shows strong synteny with the original gene arrangement of Drosophila yakuba Burla, 1954 without rearrangement. The M. indica mitochondrial genome characteristics were analyzed, and phylogenetic trees of Pentatomidae were reconstructed using Bayesian methods based on different datasets of the mitochondrial genome datasets. Phylogenetic analysis shows that M. indica belongs to Pentaotominae and form a sister-group with Anaxilaus musgravei Gross, 1976, and Asopinae is highly supported as monophyletic. Molecular clock analysis estimates a divergence time of Pentatomidae of 122.75 Mya (95% HPD: 98.76-145.43 Mya), within the Mesozoic Cretaceous; the divergence time of M. indica and A. musgravii was no later than 50.50 Mya (95% HPD: 37.20-64.80 Mya). In addition, the divergence time of Asopinae was 62.32 Mya (95% HPD: 47.08-78.23 Mya), which was in the Paleogene of the Cenozoic era. This study is of great significance for reconstructing the phylogeny of Pentatomidae and providing insights into its evolutionary history.

Host plant preference of Lygus hesperus (Hemiptera: Miridae) in 4 field crops: potato, alfalfa, carrot, and pea.

The western tarnished plant bug, Lygus hesperus (Knight), has emerged as a pest of potatoes (Solanum tuberosum L.) in the Lower Columbia Basin of Oregon and Washington. This species is generally found infesting several other field-grown crops in the region; however, their host preference is poorly understood. Thus, greenhouse cage experiments were conducted to evaluate L. hesperus host preference by simultaneously presenting adults with 4 host plants: potato, alfalfa, Medicago sativa L., carrot, Daucus carota L., and pea, Pisum sativum L. In addition, an oviposition test was conducted. The results indicated that L. hesperus actively chose as a host and as an oviposition substrate among the 4 host plants. We found a significantly higher number of adults on alfalfa and potato plants over carrot or pea plants at 6 h, 24 h, and 48 h after adults were released into the cage. However, 96 h after release, more L. hesperus were found in alfalfa. In addition, female L. hesperus strongly preferred potato and alfalfa plants as an oviposition substrate over carrot and pea plants at 96 h after release.

Thirty-four new species of Rhagovelia (Heteroptera: Veliidae) from the East Papua Composite Terrane, far eastern New Guinea.

Thirty-four new species of Rhagovelia are described from the East Papua Composite Terrane of far eastern New Guinea. The new taxa described from this area are as follows: R. yela, R. woa, and R. mbo from Rossel Island; R. tagula, R. kolukolu, and R. riu from Tagula Island; R. bwagabwaga from Misima Island; R. suloga from Woodlark Island; R. torrenticola and R. elongata from Goodenough Island; R. awaetowa from Fergusson Island; R. dibuwa from Normanby Island; R. basima from Fergusson and Normanby islands; R. kalawai from Sideia and Basilaki islands; R. guiagoila from Basilaki, Sideia and Sariba islands; R. tufi, R. bowutu, R. obscura, R. upalai, R. antap, R. goilala, R. udabe, R. watuti, R. peninsularis, R. auga, R. aviavi, R. tekadu, R. sapoi, R. mimani, R. dinga, R. ivimkana, R. loriae, R. grisea, and R. cheesmanae from the Owen Stanley Range of eastern New Guinea. Redescriptions are also provided for five previously described species occurring in this portion of New Guinea: R. peggiae Kirkaldy, R. hirsuta Lansbury, R. priori Lansbury, R. caesius Lansbury and R. aureospicata Lansbury. A regional key is provided for these 39 species of Rhagovelia occurring in the Papuan Peninsula and adjacent island groups, accompanied by figures of the male parameres and other diagnostic morphological structures, and distribution maps for all species.

Studies in the New World tribe Anisoscelini Laporte, 1832 (Heteroptera: Coreidae: Coreinae): updated distributions, nomenclatural changes, and keys to the genera of the tribe and the species of Anisoscelis Latreille, 1829 and Bitta Osuna, 1984.

Ninety new country records are recorded for 44 species of Anisoscelini Laporte, 1832 (Heteroptera: Coreidae: Coreinae). Informal distributional records are recognized and included, and updated distributions are provided for all accounted species. The following new synonymy is proposed: Malvana Stl, 1865 (= Belonomus Uhler, 1869, n. syn.) and Malvana serrulata Stl, 1865 (= Belonomus annulaticornis Uhler, 1869, n. syn.). The rank of one genus is reinstated: Bitta Osuna, 1984, stat. resurr. (formerly a subgenus of Anisoscelis Latreille, 1829). The following new or restored combinations are proposed: Bitta affinis (Westwood, 1840), comb. reins., Bitta alipes (Gurin-Mneville, 1833), comb. reins., Bitta gradadia (Distant, 1881), comb. reins., Bitta hymeniphera (Westwood, 1840), comb. reins., Bitta lurida (Brailovsky, 2016), comb. nov., and Bitta podalica Brailovsky & Mayorga, 1995, comb. reins.. We also present dichotomous keys to the twenty-nine genera of Anisoscelini, and to the species of the genera Anisoscelis Latreille, 1829 and Bitta Osuna, 1984.

Xenobates indicus sp. nov. (Hemiptera: Gerromorpha: Haloveliidae) from India, the first species of the genus described from the Indian subcontinent.

Xenobates indicus sp. nov. is described from Tamil Nadu and West Bengal, India. It constitutes the first species of the genus from the Indian subcontinent. The new species can be identified by its large size when compared to its closely related species and the presence of setal fringe on the posterior margin of mediotergite VIII of female. Key to the species of Xenobates from South and Southeast Asia and the list of world species are provided (Table 1).

Taxonomic corrections on Oriental Anthocoridae (Hemiptera: Heteroptera) described by Bertil Poppius.

Five species of Oriental Anthocoridae (Hemiptera: Heteroptera) described by Robert Bertil Poppius are revised based on their type materials. The following new combinations and new junior subjective synonyms are proposed: Amphiareus constrictus (Stl, 1860) = Cardiastethus laeviusculus Poppius, 1915, syn. nov.; Lippomanus longiceps (Poppius, 1915), comb. nov. (transferred from Cardiastethus) = Lippomanus brevicornis Yamada & Hirowatari, 2004, syn. nov.; Alofa sodalis (B. White, 1878) = Cardiastethus minutus Poppius, 1909, syn. nov.; Physopleurella obscura Poppius, 1909 (recognized as valid species) = P. nigrifemora Yamada & Hirowatari, 2007, syn. nov. Lectotypes are designated for the following species: Cardiastethus laeviusculus Poppius, 1915; Cardiastethus pilosus Poppius, 1909.

Diversity of true bugs (Insecta: Hemiptera: Heteroptera) from the El Impenetrable National Park, Argentina.

The study of the Heteroptera (Hemiptera) fauna of the El Impenetrable National Park, resulted in an inventory composed of: Alydidae (2 spp.), Aradidae (1 sp.), Belostomatidae (5 spp.), Berytidae (1 sp.), Blissidae (1 sp.), Coreidae (11 spp.), Corixidae (2 spp.), Geocoridae (1 sp.), Gerridae (1 sp.), Hebridae (1 sp.), Largidae (4 spp.), Lygaeidae (5 spp.), Miridae (17 spp.), Nabidae (1 sp.), Notonectidae (1 sp.), Oxycarenidae (1 sp.), Pachygronthidae (1 sp.), Pachynomidae (2 spp.), Pentatomidae (16 spp.), Pleidae (1 sp.), Pyrrhocoridae (1 sp.), Reduviidae (30 spp.), Rhopalidae (5 spp.), Rhyparochromidae (12 spp.), Saldidae (1 sp.), Scutelleridae (2 spp.), Tingidae (1 sp.), and Veliidae (1 sp.). These findings include six new records for the Argentinean fauna: Prytanes foedus (Stl), Saldula pallipes (Fabricius), Camirus brevilinea (Walker), Atopozelus opsimus Elkins, Doldina bicarinata Stl, Rocconota sextuberculata St and 39 new records for Chaco Province.

Identity on Filchneria heteroptera (Wu, 1938) (Plecoptera: Perlodidae) with a new record of Paraleuctra cercia (Okamoto, 1922) from China.

Filchneria heteroptera (Wu, 1938) is rediscovered from Heilongjiang Province of northeastern China. A supplementary description and illustrations including aedeagal structures based on newly collected specimens are provided. Filchneria dongruihangi Chen, 2020 is considered here as a junior synonym of F. heteroptera (Wu, 1938). Paraleuctra cercia (Okamoto, 1922) is reported from Liaoning and Heilongjiang provinces, China for the first time.

Review of the genus Tetralicia (Hemiptera: Aleyrodidae) and description of two new species of whiteflies found on avocado trees in Peru.

Two new species, Tetralicia sawyeri n. sp. and Aleuroplatus martini n. sp. found on avocado (Persea americana) trees in Peru are described and illustrated. The synonymy of Aleuropleurocelus Drews & Sampson, 1956 n. syn. with Tetralicia Harrison, 1917 is proposed and a review and an illustrated key to the 39 species of Tetralicia of the world based on characteristics of the puparia is provided. Thirty-three species are transferred from Aleuropleurocelus to Tetralicia. A lectotype is designated for Aleurodes abnormis Quaintance, 1900. Aleurotrachelus gratiosus Bondar, 1923 is transferred to the genus Aleuroplatus. Paracarniella mexicana (Distant) and Adparaproba cf. yungensis Carvalho (Hemiptera: Miridae) are recorded for the first time in Peru and are important predators of both new whitefly species. Other natural enemies of these whiteflies found in the study include predatory species: Nephaspis isabelae Gonzlez (Coccinellidae), Chrysoperla sp., Ceraeochrysa sp. (Chrysopidae) and Gasteracantha cancriformis L. (Araneidae) as well as Encarsia brasiliensis Hempel, a common whitefly parasitoid in the Neotropics. A key to the New World genera of whiteflies similar to Aleuroplatus and Tetralicia is provided.

Ethno-entomotherapeutic and metabolite profiling of Coridius chinensis (Dallas), a traditional edible insect species of North-East India.

Edible insects possess several health enhancing properties and play an important role in human nutrition. Coridius chinensis is an edible insect that is considered food and claimed as traditional medicine. In the present study, nutritional contents, chemical composition, antioxidant, and anti-inflammatory properties of C. chinensis were analyzed. It was found that the insect sample contains 50.46% moisture, 44.65% protein, 4.45% carbohydrate, 39.42% crude fats, 3.53% ash and 576.11 (Kcal/100 g) energy. Our study highlighted the presence of a significant amount of phenol and flavonoids. The C. chinensis hydro-alcoholic extract showed high antioxidant property and anti-inflammatory activity. GCMS analysis identified 61 volatile compounds. LC-MS analysis of hydroalcoholic extract of C. chinensis revealed the presence of compounds such as etodolac glucuronide, morphine 3-glucuronide, ecgonine, ecgonine methyl ester, sufentanil, and palmitoyl ethanololamide. These findings suggest that C. chinensis species can be employed as a valuable food source with excellent therapeutic properties.

Checklist and distribution of Nepomorpha (Hemiptera: Heteroptera) from China.

An updated catalog of the infraorder Nepomorpha from China is provided based on literature reports, museum specimens, and field collections. In total, 214 species of Nepomorpha are listed in 6 superfamilies, 11 families, and 37 genera, including: Aphelocheiridae (1 genus, 27 species), Belostomatidae (3 genera, 7 species), Corixidae (9 genera, 52 species), Gelastocoridae (1 genus, 3 species), Helotrephidae (5 genera, 25 species), Micronectidae (1 genus, 28 species), Naucoridae (7 genera, 12 species), Nepidae (5 genera, 21 species), Notonectidae (4 genera, 32 species), Ochteridae (1 genus, 2 species) and Pleidae (1 genus, 5 species). Paraplea liturata (Fieber, 1844) is reported from mainland China for the first time. Distribution maps are provided for most species and are based on museum specimens and our field collections.

Corythauma ayyari (Insecta, Heteroptera, Tingidae) depends on its host plant to spread in Europe.

Biological invasions increase with the intensity of globalization, human activities, and climate change. Insects represent a high potential of invasive species due to their adaptability to new environment. We analysed here the potential of an Asian phytophagous bug, Corythauma ayyari (Heteroptera, Tingidae) to become widespread, recently recorded in Europe, and that depends on Jasminum spp., an ornamental plant widespread in Europe. We modelled its current distribution, projected it into the future and tested its niche overlap between native and invaded areas. When considering the host plants as environmental variables, the analysis shows that C. ayyari shifted to a new ecological niche but its distribution is restricted by its host plant distribution. Including or excluding the host plants as environmental variables has an impact on C. ayyari distribution. We recommend to consider host plant interactions when dealing with niche modelling of phytophagous species.