Morphology of the Mandibular and Intramandibular Glands of Army Ant Workers of Labidus praedator (Smith 1858) and Labidus coecus (Latreille 1802) (Formicidae: Dorylinae).

Social insects are characterized by having a wide diversity of exocrine glands, with highlights for ants with about 85 glands spreading throughout the body. The mandibular and intramandibular glands are associated with the production of pheromones. The army ants (Dorylinae) play an important role in the structure of the invertebrate community because they are efficient predators and provide suitable conditions for various animals following their invasions in the food search. Labidus coecus (Latreille) is an underground-ameliorating ant and Labidus praedator (Smith) is a generalist surface predator which can deplete invertebrate biomass by up to 75%. This work investigated the morphology of the mandibular and intramandibular glands of L. praedator and L. coecus workers. The glands were analyzed by light microscopy, histochemistry, and scanning electron microscopy. The mandibular and intramandibular glands of the two species were classified as class III glands. The data on the morphology of the mandibular glands has revealed that they have characteristics in common with other subfamilies. The intramandibular glands of the two species of Labidus have similar morphology and chemical composition, which indicates that the components of these glands can have the same function despite their different habits.

Repellency, contact toxicity, and anti-oviposition effects of three ethanol-extracted plant essential oils on Bemisia tabaci (Hemiptera: Aleyrodidae).

There are more than 1200 species of whiteflies found across the globe. Due to the high level of resistance of whitefly against synthetic insecticides, alternate pest management measures have their significance. Plant essential oils (EOs) affect insect pests in many ways, such as via stimulatory, deterrent, toxic, and hormonal effects. This study was designed to determine the repellency of EOs, toxicity, and oviposition deterrent activities of Allium ascalonicum, Cinnamomum camphora, and Mentha haplocalyx against adult whiteflies. In repellency determination experiments, a single tomato plant was treated with 10 ml of ethanol-extracted EO with 1000 ppm concentration. Results showed that C. camphora EO was the most repellent for whitefly compared to M. haplocalyx and A. ascalonicum. The oviposition deterrent experiments revealed that C. camphora has the highest oviposition deterrent effect, followed by M. haplocalyx and A. ascalonicum. A single plant treatment method was used to assess the contact toxicity of three EOs against whitefly after 12, 24, 48, and 72 h of exposure. The results revealed that C. camphora is more toxic to whitefly than M. haplocalyx and A. ascalonicum. After determining the antagonistic effects of these EOs, the oils were analyzed using gas chromatography/mass spectrometry to identify the chemical components. It can be concluded that C. camphora is the most effective oil EO in terms of toxicity, repellence, and oviposition deterrence, followed by M. haplocalyx and A. ascalonicum under greenhouse conditions. Our results introduce some new eco-friendly plant EOs to control whiteflies.

The complete mitochondrial genome of Attacus atlas formosanus Villiard, 1969 (Lepidoptera: Saturniidae).

The complete mitochondrial genome (mitogenome) of Attacus atlas formosanus (Villiard, 1969) is 15,280 bp in length, with the typical gene content and arrangement usually observed in Insecta. It contains 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and one AT-rich region. The overall nucleotide composition of the mitogenome was 39.8% A, 12.9% C, 7.7% G, and 39.6% T, with an A + T bias of 79.4%. Phylogenetic analyses of 23 species in Saturniidae and 3 species in Bombycidae by Bayesian inference showed that A. atlas formosanus belonged to the Tribe Attacini, closely related to Tribe Saturniini. Besides, A. atlas formosanus is closely related to A. atlas with 99% sequence identity. This result well supported the taxonomic position of Saturniidae and their close relationship with the family Bombycidae.

Effects of the copper oxide nanoparticles (CuO NPs) on Galleria mellonella hemocytes.

In this study, 38 nm-sized and flake-like-shaped CuO NPs (10, 50, 100, 150 µg/10 µl/larva) were force-fed to fourth instar (100 ± 20 mg) Galleria mellonella (Lepidoptera: Pyralidae) larvae under the laboratory conditions. The effects of CuO NPs on total hemocyte counts (THCs) and the frequency of viable, mitotic, apoptotic, necrotic, and micronucleated hemocyte indices were detected with the double-staining protocol by hematoxylin and eosin (H&E) stains. The total hemocyte counts (THCs) did not change significantly in G. mellonella larvae at all concentrations for 24 h and 72 h post-force-feeding treatment. The ratio of viable hemocytes decreased at 50, 100, 150 µg/10 µl concentrations in 24 h and 72 h when compared with untreated larvae. The increases in the percentage of mitotic and micronucleated hemocytes were statistically significant at 150 µg/10 µl in 24 h. The results showed that high concentrations (>10 µg/10 µl) of CuO NPs increased the percentage of apoptotic hemocytes in 24 h. 100 and 150 µg/10 µl of CuO NPs caused a significant increase in the percentage of necrotic hemocytes in 24 h. The decrease in the percentage of mitotic hemocytes at 10, 100 and 150 µg/10 µl in 72 h was statistically significant. Apoptotic hemocytes increased and were found to be higher at 100 and 150 µg/10 µl of CuO NPs in 72 h in comparison with the untreated larvae. Finally, we observed an increase in the percentage of necrotic hemocytes at 150 µg/10 µl in 72 h.

Morphology of the male and female reproductive tracts of virgin and mated Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae).

Predatory insects have reproductive organs rich in complex changes that may be responsible for the success of their population growth. The species Chrysoperla externa is a predator used in biological control programs in Latin America. However, there is no morphological data about the morphology of the reproductive tract in this insect. This study describes the morphology of the reproductive organs of virgin and mated C. externa male and female. The male has a pair of testes yellow in color and five pairs of accessory glands closely associated with the seminal vesicles. The testis follicles are twisted filled with cysts in different developmental stages. The pair of ovaries in the females shows asymmetry with 9-11 ovarioles per ovary with oocytes in different developmental stages and a spherical spermatheca. Virgin and mated males have no differences in the size of the testes, seminal vesicle, and accessory glands. C. externa females show morphological changes in the reproductive tract according to sexual maturation, which is triggered by mating. The ovary activation occurs after female mating. The ovaries are of merotistic polytrophic type. The spermathecal reservoir is lined by a flattened epithelium with a thin cuticular intima and associated with well-developed muscles. It is concluded that the reproductive tract of C. externa is similar in virgin and mated males and females. Egg production is activated only after mating and the development of reproductive tract structures is faster in mated females.

Species richness and composition of Neuroptera in the forests fregments of the Taurus Mountains Range, Turkey.

In this study, diversity, species richness and composition of Neuroptera has been studied in the forest edges and fragments in the Taurus Mountain Range, southern Turkey. Sampling for species collection was carried out from April 2017 to September 2018 at different distances from the forest center, i.e., (0-500 m), forest mid-interior (501-1000 m), and forest edge (1001-3000 m). A total of 975 adults were collected frequently belonging to the families Ascalaphidae, Coniopterygidae, and Hemerobiidae from the forest edges while Chrysopidae and Myrmeleontidae were most common along the mid-interior regions of the forest. Majority of adutls caught from the mid-interior region comprised of female adults while the males of most species were abundant along the forest edges. Although the forest center shows the largest value for the Dominance species-diversity index and the smallest value for the Shannon index, forest edge was found highest for the Simpson index. The abundance of Neuroptera decreased with wind speed but increased with the temperature in the edge regions. Principal Component Analysis (PCA) indicated that some environmental and habitat variables, e.g. wind speed, temperature, and distance to the forest center, mid-interior and edge, accounted for species distribution patterns in Neuroptera. In the forest center, a linear correlation between wind speed, temperature and specimen abundance was recorded, while these factors were found negatively correlated with specimens abundance in the mid-interior regions of the forest.

Additional knowledge respecting taxonomy of the social wasp genus Ropalidia (Hymenoptera: Vespidae: Polistinae) from Vietnam, with new records of three species and an updated key to species.

Species composition of social wasps of the genus Ropalidia from Vietnam is reported, with 24 species having been recorded. Of those, three species are newly recorded for the Vietnamese fauna, namely Ropalidia binghami van der Vecht, 1941, R. parartifex Tan van Achterberg, 2014 and R. variegata (Smith, 1852). The presence of R. sumatrae (Weber, 1801) in Vietnam is confirmed. An updated key to all recorded species of the genus Ropalidia from Vietnam is also provided.

Taxonomic studies on the genus Orancistrocerus van der Vecht, 1963 (Hymenoptera: Vespidae: Eumeninae) from Vietnam, with description of a new species.

Two species of the genus Orancistrocerus van der Vecht, 1963 from Vietnam are recorded. Of them, a new species, O. altus sp. nov. from Lang Son province in the northern part of Vietnam is described and illustrated. In addition, one subspecies, O. aterrimus nigriceps van der Vecht, 1963 is newly recorded from China.

Anatomy, Histology, and Ultrastructure of Salivary Glands of the Burrower Bug, Scaptocoris castanea (Hemiptera: Cydnidae).

The burrower bug Scaptocoris castanea Perty, 1830 (Hemiptera: Cydnidae) is an agricultural pest feeding on roots of several crops. The histology and ultrastructure of the salivary glands of S. castanea were described. The salivary system has a pair of principal salivary glands and a pair of accessory salivary glands. The principal salivary gland is bilobed with anterior and posterior lobes joined by a hilus where an excretory duct occurs. The accessory salivary gland is tubular with a narrow lumen that opens into the hilus near the excretory duct, suggesting that its secretion is stored in the lumen of the principal gland. The cytoplasm of the secretory cells is rich in the rough endoplasmic reticulum, secretory vesicles with different electron densities and mitochondria. At the base of the accessory gland epithelium, there were scattered cells that do not reach the gland lumen, with the cytoplasm rich in the rough endoplasmic reticulum, indicating a role in protein production. Data show that principal and accessory salivary glands of S. castanea produce proteinaceous saliva. This is the first morphological description of the S. castanea salivary system that is similar to other Hemiptera Pentatomomorpha, but with occurrence of basal cells in the accessory salivary gland.

Cytotoxicity of Piper aduncum (Piperaceae) essential oil in brown stink bug Euschistus heros (Heteroptera: Pentatomidae).

Euschistus heros (F.) (Hemiptera: Pentatomidae) is a soybean pest in Brazil, controlled with synthetic chemical insecticides, which may be harmful to the environment and humans, as well as to select pest resistant strains. The research for new pest control strategies such as the use of plant essential oils has been increased due to the selectivity and biodegradation of these molecules. The objective was to evaluate the cytological changes in the salivary glands, fat body and midgut of E. heros exposed to different concentrations of essential oil of Piper aduncum L. (Piperales: Piperaceae), which the main compounds were identified as myristicin 30.03%, aromadendrene 9.20%, dillapiole 8.43%, α-serinene 7.31%, tridecane 6.26%, γ-elemene 4.58% and o-cymene 4.20%. The essential oil of P. aduncum was toxic for E. heros with LD50 = 36.23 mg per insect and LD90 = 50.42 mg per insect. Cytological changes such as tissue disruption, increase in mitochondria population, and glycogen and lipid depletion occur in the fat body cells, whereas salivary glands and midgut are not affected by this essential oil. Results suggest that P. aduncum essential oil causes fat body cellular stress, which may compromise some physiological processes for the insect survival.

Exposure to spinosad induces histopathological and cytotoxic effects on the salivary complex of the non-target predator Podisus nigrispinus.

In integrated pest management systems, biological and chemical controls must be compatible. The insecticide spinosad affects some non-target insects and might compromise their fitness. The objective of this study was to evaluate the histopathological and cytotoxic effects of spinosad on the salivary complex of the predatory bug Podisus nigrispinus (Heteroptera: Pentatomidae). Spinosad toxicity and insect survival were determined using six concentrations of insecticide. Ultrastructural changes and cell death of salivary glands were analyzed after P. nigrispinus exposure to spinosad LC50 (3.15 µg L-1). The insecticide caused toxicity to P. nigrispinus; survival was 32% after 48 h of exposure to LC50. The main histological changes in the salivary complex were disorganization of the epithelium, cytoplasmic vacuolization, and apocrine secretion into the gland lumen. Cytotoxic effects, such as release of granules and vacuoles into the lumen, presence of autophagosomes, enlargement of basal plasma membrane infoldings, and apoptosis, were observed. Spinosad causes toxicity, decreases survival, and changes the histology and cytology of the P. nigrispinus salivary complex. The results suggest that the cellular stress induced by the insecticide affects extra-oral digestion, compromising the potential of P. nigrispinus as a biological pest control agent.

The Mitochondrial Genomes of Neuropteridan Insects and Implications for the Phylogeny of Neuroptera.

The higher-level phylogeny of Neuroptera is explored here based on the newly determined mitochondrial genomic data, with a special focus on the interfamilial relationships of this group. Despite considerable progress in our understanding of neuropteran relationships, several mutually exclusive hypotheses have come out according to morphology-based analyses and molecular sequence data. The evaluation of these hypotheses is hampered by the limited taxonomic coverage of previous studies. In this paper, we sequenced four mitochondrial genomes to improve the taxonomic sampling for families: Myrmeleontidae, Ascalaphidae and outgroup Corydalidae. Phylogenetic analyses were run using various inference methods to (1) confirm that Coniopterygidae is sister to all other Neuroptera; (2) place Hemerobiidae as sister to Chrysopidae; (3) support the monophyly of Myrmeleontiformia and define its interfamilial relationships; and (4) recover Myrmeleontidae as paraphyletic due to the nested Ascalaphidae.

Toxicity and cytotoxicity of the insecticide imidacloprid in the midgut of the predatory bug, Podisus nigrispinus.

The selectivity of insecticides on natural enemies in pest control are an important strategy for Integrated Pest Management. However, insecticides can have side effects on non-target organisms such as natural enemies. This study evaluated the histological and cytological changes mediated by the sublethal concentration of the imidacloprid insecticide on the midgut of non-target predator Podisus nigrispinus (Heteroptera: Pentatomidae), used in the biological control of pests. Imidacloprid was toxic for P. nigrispinus with LC50 = 3.75 mg L-1 and survival of 51.8%. This sublethal concentration of imidacloprid causes histological alterations in the midgut epithelium and cytotoxic features were irregular border epithelium, cytoplasmic vacuolation, and apocrine secretions in the first 6 h after exposure with the insecticide. Apoptosis in the digestive cells occurs after 12 h of exposure in the midgut. These results suggest that imidacloprid may affect the digestive physiology of P. nigrispinus and compromise the effective predation of this insect a biological control agent. The associated use of this insecticide with the predator in pest control should be carefully evaluated.

Contribution to the genus Okinawepipona Yamane (Hymenoptera: Vespidae: Eumeninae) from Vietnam, with description of a new species.

A new species of the genus Okinawepipona Yamane from Vietnam is described and figured: Okinawepipona yty Nguyen, sp. nov. (northern Vietnam). Biology of O. yty Nguyen, sp. nov. and O. nigra Nguyen Xu, 2014 is recorded. A key to the four species known in the genus is provided.

Additions to knowledge of the paper wasp Polistes delhiensis Das and Gupta, 1989 (Hymenoptera: Vespidae: Polistinae) from Vietnam with description of the male and nest.

Notes on the paper wasp of the genus Polistes, Polistes delhiensis Das and Gupta, 1989 (Hymenoptera: Vespidae: Polistinae) from Vietnam are presented. The species has two color forms of the clypeus: brightly colored specimens were collected in the southern part of the range and darker colored specimens were collected in the northern part. Based on morphological and DNA data analysis, it is confirmed that both color forms belong to Polistes delhiensis. The male of this species is described for the first time and its fully-developed nest is also described.

Permethrin induces histological and cytological changes in the midgut of the predatory bug, Podisus nigrispinus.

Insecticides used in the agriculture and forestry have side effects on non-target organisms used as natural enemies. This study evaluated the histopathology and cytotoxicity of permethrin on the midgut of the non-target predatory bug, Podisus nigrispinus (Heteroptera: Pentatomidae) used in the biological control of pest insects. The toxicity and survival of this insect were determined using six concentrations of permethrin via ingestion. Histological and ultraestutural changes of the midgut of P. nigrispinus were analyzed after exposure to permethrin. The insecticide caused toxicity in P. nigrispinus with LC50 = 0.46 µg L-1 and survival of 47% after 72 h of exposure. The histological changes in the midgut were irregularly bordered epithelium, cytoplasmic vacuolization and apocrine secretions in the lumen after 6 h following exposure to the insecticide. Cytotoxic effects such as granules and vacuoles secreted into the lumen, presence of autophagosomes, and dilatation of infolds of the basal plasma membrane were observed in the three regions of the midgut. Cells of the midgut in apoptosis occurred after 12 h of exposure. Permethrin causes toxic effects, inhibits survival, and produces changes in the histology and cytology of the midgut in P. nigrispinus, suggesting that the cell stress induced by this insecticide can disrupt physiological processes such as digestion, compromising the potential of the predator as a biological control agent of pests. The low selectivity of permethrin to a non-target organism such as the predatory bug, P. nigrispinus indicates that the associated use of this insecticide in biological control should be better evaluated.

Species of the Polistes (Polistella) (Hymenoptera: Vespidae: Polistinae) from Vietnam, with description of a new species and a pictorial key.

Twenty seven species of the subgenus Polistella Ashmead, 1904 are recorded from Vietnam. Polistes chuyangsin Nguyen Nguyen sp. nov. and its nest are described and figured. A pictorial key to Vietnamese species of the subgenus is provided.

A new record of the genus Orientalicesa Koçak Kemal, 2010 (Hymenoptera: Vespidae: Eumeninae) from Vietnam.

The genus Orientalicesa has six species, and all of them have been recorded in the Oriental region (including Indonesia, Malaysia, Phillippines, Laos, China). In this paper, the genus Orientalicesa is newly recorded from Vietnam, represented by one species O. confasciatus Tan and Carpenter. This species was mistakenly redescribed as Stenodyneriellus rangpocus Kumar, Carpenter Kishore, 2017. A new synonym of O. confasciatus is proposed, and that species is a new record for India.

Third instars larvae of Gepus gibbosus Hölzel, 1968 (Neuroptera: Myrmeleontindae).

The third instar larva of Gepus gibbosus Hölzel, 1968 are described and figured for the first time using light and scanning electron microscopy. The females were collected from Derik, Mardin Province, Turkey and maintained in the laboratory. The morphology of different parts of the larva such as head, mandibles, and antennae are described and illustrated. G. gibbosus is new for the Turkish fauna.