Pine pest aphids of the genus Eulachnus (Hemiptera: Aphididae: Lachninae): how far can their range extend?

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What is the economic threshold of soybean aphids (Hemiptera: Aphididae) in enemy-free space?

Soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is a serious pest of soybean, Glycine max (L.) Merr., in the North Central United States. Current management recommendations rely on the application of insecticides based on an economic threshold (ET) of 250 aphids per plant. Natural enemies are important in slowing the increase of aphid populations and can prevent them from reaching levels that can cause economic losses. However, biological control of A. glycines is inconsistent and can be affected negatively by the intensity of agricultural activity. We measured the impact of a natural-enemy-free environment on the capacity of the current ET to limit yield loss. In 2008 and 2009, caged microplots were assigned to one of three treatments: plants kept aphid-free (referred to as the control), plants that experienced a population of 250 aphids per plant (integrated pest management [IPM]), and plants that experienced unlimited aphid population growth (unlimited). The population growth rate of aphids in the unlimited treatment for the 10 d after the application of insecticides to the IPM treatment was calculated using linear regression. The linear equation was solved to determine the mean number of days between the ET and the EIL for an aphid population in absence of predators. The number of days was determined to be 6.97 +/- 1.11 d. The 2-yr average yield for the IPM treatment was 99.93% of the control treatment. Our study suggests the current soybean aphid ET of 250 aphids per plant can effectively protect yield even if the impact of natural enemies is reduced.     

Goodbye Halteria? The thoracic morphology of Endopterygota (Insecta) and its phylogenetic implications

Characters of the thorax of 30 representatives of all endopterygote orders and four hemimetabolous outgroup taxa were examined. In total, 126 characters potentially useful for phylogenetic reconstruction are discussed and presented as a data matrix. The thoracic features were analysed with different approaches combined with an additional large set of morphological data. Endopterygota were confirmed as monophyletic and new morphological autapomorphies of the group are suggested. The highly controversial Strepsiptera are not placed as sistergroup of Diptera (Halteria‐concept) but consistently as sistergroup of Coleoptera. This clade was mainly supported by characters associated with posteromotorism. The traditionally proposed relationship of Neuropterida + Coleoptera was not confirmed. Hymenoptera was placed as sistergroup of all remaining orders in parsimony analyses. The inclusion of Strepsiptera + Coleoptera in Mecopterida in parsimony analyses is probably artificial and potential thoracic autapomorphies of Mecopterida in the traditional sense are suggested. Mecopterida are confirmed as a clade in Bayesian analyses. Amphiesmenoptera and Antliophora are well supported. The paraphyly of Mecoptera is due to a clade comprising Nannochoristidae and Siphonaptera + Diptera. The phylogenetic reconstruction using characters of the thorax is impeded by functional constraints, parallel losses, a general trend to reinforce the skeleton and to simplify the muscular apparatus, and also by different specializations occurring in potential outgroup taxa. The addition of a large additional morphological data set only partly compensated for these problems. It is apparent that the inclusion of more outgroup and ingroup taxa is required, notably presumably basal representatives of Mecoptera, Trichoptera, and Diptera. This may reduce the effect of an artificial attraction of branches caused by homoplasy, notably character losses occurring within different lineages.© The Willi Hennig Society 2010.     

Mitochondrial COI and morphological specificity of the mealy aphids (Hyalopterus ssp.) collected from different?hosts in Europe (Hemiptera,Aphididae)

Forty three European population samples of mealy aphids from various winter and summer host plants were attributed to respective species of Hyalopterus by means of their partial sequences of mitochondrial COI gene. Used Hyalopterus samples emerged as monophyletic relative to outgroup and formed three major clades representing three host specific mealy aphid species in the Neighbor joining, Maximum parsimony, Maximum likelihood and Bayesian inference trees. Hyalopterus pruni and Hyalopterus persikonus emerged as a sister species, whilst Hyalopterus amygdali was located basally. Samples representing different clades in the molecular trees were used for canonical discrimination analysis based on twenty two morphological characters. Length of the median dorsal head hair enabled a 97.3 % separation of Hyalopterus amygdali from the remaining two species. No single character enabled satisfactory discrimination between apterous viviparous females of Hyalopterus pruni and Hyalopterus persikonus. A modified key for the morphological identification of Hyalopterus species is suggested and their taxonomic status discussed.     

Ant–aphid relations in the south of Western Siberia (Hymenoptera: Formicidae; Hemiptera: Aphididae)

Aphids, the main suppliers of energy-rich honeydew, play an important role in the life of ants. However, the data on the trophobiotic ant–aphid associations in the majority of regions are still limited. We present the first data on the ant–aphid relations in the south of Western Siberia. Investigations were carried out in the most typical biotopes of forest-steppe and steppe zones in the territory of Novosibirsk and Kurgan regions (Russia) during 1993–2014. There were revealed 35 species of ants and 198 species of aphids. Detected 456 ant–aphid associations involved 28 ant species and 134 myrmecophilous aphids. Seven ant species were found to consume honeydew of 9 non-myrmecophilous aphids, scraping it from the plant. This behaviour is typical of subdominant and subordinate ants which do not protect their foraging areas. Ants associate with various numbers of aphid species. About 36% of ants attended aphid colonies of less than 5 species. The largest number of myrmecophilous aphids is associated with L. niger (Linnaeus, 1758) (103 species), Formica pratensis Retzius, 1783 (50), Formica rufa group (25–33), F. (Serviformica) fusca Linnaeus, 1758 (26) and F. (S.) cunicularia Latreille, 1798 (27). Different ants play unequal roles in the formation of trophobiotic interactions with aphids. Due to complex territorial and foraging behaviour, including high functional specialization among honeydew collectors, dominant ants of Formica s. str. are one of the leaders in this process. The role of L. niger and Formica ants of the subgenus Serviformica requires further detailed investigation.     

DL-β-Aminobutyric Acid-Induced Resistance in Soybean against Aphis glycines Matsumura (Hemiptera: Aphididae)

Priming can improve plant innate capability to deal with the stresses caused by both biotic and abiotic factors. In this study, the effect of DL-β-amino-n-butyric acid (BABA) against Aphis glycines Matsumura, the soybean aphid (SA) was evaluated. We found that 25 mM BABA as a root drench had minimal adverse impact on plant growth and also efficiently protected soybean from SA infestation. In both choice and non-choice tests, SA number was significantly decreased to a low level in soybean seedlings drenched with 25 mM BABA compared to the control counterparts. BABA treatment resulted in a significant increase in the activities of several defense enzymes, such as phenylalanine ammonia-lyase (PAL), peroxidase (POX), polyphenol oxidase (PPO), chitinase (CHI), and β-1, 3-glucanase (GLU) in soybean seedlings attacked by aphid. Meanwhile, the induction of 15 defense-related genes by aphid, such as AOS, CHS, MMP2, NPR1-1, NPR1-2, and PR genes, were significantly augmented in BABA-treated soybean seedlings. Our study suggest that BABA application is a promising way to enhance soybean resistance against SA.     

Functional morphology of Gené's organ inHaemaphysalis longicornis (Acari: Ixodidae)

The structure and function of Gené's organ, which secretes the egg wax, were investigated inHaemaphysalis longicornis. The hatching rates of eggs deposited before and after the prevention of the eversion of Gené's organ were compared at the conditions of 30°C, 100% RH and soaking in liquid paraffin. The movement of Gené's organ was observed, and the structures of this organ in unfed and ovipositing females were examined with both light and scanning electron microscopes.The hatching rates of eggs without contact with Gené's organ were markedly lower (4.9%) than that of normal eggs (94.5%) even at the suitable condition for eggs (30°C, 100% RH). In contrast, the hatching rates of eggs soaked in liquid paraffin without contact of Gené's organ were considerably higher (71.8%) than that of eggs without both Gené's organ contact and soaking in liquid paraffin.When oviposition commenced, the camerostome of the female was widened by a downswing of the capitulum, the paired horns of Gené's organ emerged through it, and the oviposited egg from the genital aperture was coated with egg wax. At the same time of retraction of the horns which grip an egg, the capitulum was swung up and the egg was loaded on the scutum.Gené's organ included the outer and inner cuticles, and the outer one is highly folded like bellows when the horns of this organ were retracted into the haemocoel. The undeveloped glands lying in the peripheral region of Gené's organ in the unfed stage commenced their enlargement at the time of the onset of feeding, and they became large tubular glands in the 1-day ovipositing female. The columnar glandular cells of the tubular glands extended their domed apical region into the lumen and contained numerous secretory granules during oviposition.These results suggest that the tubular glands secrete the egg wax which is indispensable for egg survival by serving as a waterproofing agent.     

Phototactic behaviour of Pachyneuron aphidis (Hymenoptera: Pteromalidae) – hyperparasitoid of Myzus persicae (Hemiptera: Aphidiae)

We investigated the spectral sensitivity and response to light intensity of Pachyneuron aphidis (Hymenoptera: Pteromalidae), which is a common hyperparasitoid of Aphidius gifuensis (Hymenoptera: Braconidae), a key natural enemy of the green peach aphid, Myzus persicae (Hemiptera: Aphididae). To do so, we used 15 monochromatic lights (emitting various specific wavelengths from 340 to 649 nm) and white light. P. aphidis adults are diurnal insects that show a positive phototaxis to a broad spectrum of light. Significant differences were found between sexes in the phototactic responses of P. aphidis to different monochromatic lights. Female P. aphidis showed four peaks of sensitivity at 380, 450, 504 and 589 nm. Male P. aphidis show two peaks of sensitivity, one at 450 nm and second at 628 nm. P. aphidis adults showed an increased phototactic response at low intensities and a decreased phototactic response at high intensities for both UV light and blue light. This experiment will help provide a scientific basis for the development of colour traps for insect pest management.     

Functional morphology of Trichadenotecnum male and female genitalia analyzed using μCT (Insecta: Psocodea: Psocomorpha)

Although the great genital diversity of the barklouse genus Trichadenotecnum has been described in previous studies, the specific function of the genital structures during the copulation process has received less investigative attention. We reconstructed 3D-models of each structure of the male and female genitalia of Trichadenotecnum incognitum in copula and those of uncopulated male and female of Trichadenotecnum pseudomedium. By comparing the changes in male and female genital structures and related muscles in copulated and uncopulated states, the function of each genital structure can be described. During the copulation, we found that the female subgenital plate was hooked into the male body by the distal process on the male paraproct and was fixed by the male epiproct, hypandrium and phallosome. In addition, sexual coevolution was suggested by tightly contacting structures, that is, thorny male hypandrium and thickened membrane around the female spermapore plate. These results not only give us a new understanding copulation process of Trichadenotecnum, but also explain the reasons why genital structures are so divers in the genus.     

Do aphid galls provide good nutrients for the aphids?: Comparisons of amino acid concentrations in galls among Tetraneura species (Aphididae: Eriosomatinae)

Some aphid species induce leaf galls, in which the fundatrix parthenogenetically produces many nymphs. In order to ensure high performance, galls have to provide the aphids with sufficient nutrients, in particular, amino acids as a nitrogen source. We tested this hypothesis using six Tetraneura aphid species that induce closed galls. We extracted free amino acids from the whole gall tissues of unit weight and quantified the concentration of each amino acid. There were large differences in the total amino acid concentrations among galls of the Tetraneura species. Tetraneura species in which higher concentrations of total amino acids were found in the gall tended to produce larger numbers of offspring. Of the amino acids found, asparagine was predominant in the gall. The asparagine concentration in T. yezoensis galls was several hundred times as high as in control leaves. We discussed why such a high level of asparagine accumulates in aphid galls.     

Is preventative, concurrent management of the soybean aphid (Hemiptera: Aphididae) and bean leaf beetle (Coleoptera: Chrysomelidae) possible?

In Iowa, the management of insect pests in soybean, Glycine max (L.) Merr., has been complicated by the arrival of the invasive species soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), and occasional outbreaks of bean leaf beetle, Cerotoma trifurcata (F?rster) (Coleoptera: Chrysomelidae), populations leading to economic losses. Several insecticide programs designed to reduce abundance of the overwintered and first generation C. trifurcata and the incidence of bean pod mottle virus were evaluated over 3 yr (2004-2006) for their impacts on A. glycines populations, at three locations in Iowa (Floyd, Lucas, and Story counties). There was no significant overlap of either overwintered (early May) or the first (early July) generations of C. trifurcata with A. glycines, because aphids were first detected in June and they did not reach economically damaging levels until August, if at all. During this study, insecticides targeting the overwintered population or the first generation of C. trifurcata provided a limited impact on A. glycines populations compared with untreated controls, and they did not prevent economic populations from occurring. Furthermore, the highest populations of A. glycines were frequently observed when a low rate of lambda-cyhalothrin (178 ml/ha) was applied targeting the overwintered population of C. trifurcata. Soybean yields were not protected by any of the insecticide treatments. Our results indicate that the use of either early season foliar or seed-applied insecticides for C. trifurcata management is of limited value for A. glycines management.     

Macrelmis pubescens (Grouvelle, 1889) – redescription of the species,designation of a lectotype and description of its larva (Coleoptera: Elmidae)

The adult of Macrelmis pubescens (Grouvelle, 1889) is redescribed, illustrated, a lectotype designated, and new locality information provided. The lectotype is housed in the Grouvelle’s collection in the Muséum national d’Histoire naturelle, Paris, France. The larva of M. pubescens is described, illustrated and compared with the known larvae of the genus. A diagnosis for Macrelmis Motschulsky, 1860 larvae is provided.     

Taxonomic review of the lace bug genus Omoplax (Hemiptera: Heteroptera: Tingidae) endemic to “Oriental Galapagos” (the Ogasawara Islands,Japan) with the description of its new allied genus and species

In this study, we revise the lace bugs (family Tingidae) from the Ogasawara Islands, Japan (also known as the “Oriental Galapagos”). Three species belonging to two endemic genera are recognized: Acanthomoplax tomokunii gen. et sp. nov. , Omoplax desecta (Horváth, 1912), and O. majorcarinae Guilbert, 2001. A key to species is provided to facilitate the identification of Ogasawaran lace bugs.     

Revision of the plant bug genus Xenocylapus Bergroth (Hemiptera: Heteroptera: Miridae: Cylapinae), with a description of Henryfulvius gracilis – a new cylapine genus and species from Ecuador

The genus Xenocylapus Bergroth, 1922 is revised. Nine new species, Xenocylapus aculeatus sp. nov., X. aquilonius sp. nov., X. bicolor sp. nov., X. globulus sp. nov., X. heissi sp. nov., X. panamaensis sp. nov., X. serrulatus sp. nov., X. tenuis sp. nov., and X. waorani sp. nov., are described from Brazil, Honduras, Mexico, and Panama. New genus and species Henryfulvius gracilis gen. nov., sp. nov. is described from Ecuador. Illustrations of the male genitalia, color photographs of dorsal and lateral views of the adult of most species, scanning electron micrographs of selected structures of X. tenuis, and keys to species of the genus Xenocylapus are provided.     

The soapberry bug,Jadera haematoloma (Insecta,Hemiptera, Rhopalidae): First Asian record,with?a?review of bionomics

The soapberry bug, Jadera haematoloma (Herrich-Schäffer, 1847) (Insecta: Hemiptera: Heteroptera: Rhopalidae: Serinethinae), a species native in tropical and subtropical regions of the New World and accidentally introduced to Hawaii, is reported for the first time from Asia (Taiwan). This record represents the first occurrence of the species in Asia. Stable populations composed of hundreds of specimens were found in seven localities of Kaohsiung City and one locality in Tainan City, and a single specimen was observed in Chiayi County. Aggregating adults and larvae fed in large numbers on the sapindacean plants Cardiospermum halicacabum L. and Koelreuteria elegans (Seem.) A. C. Smith ssp. formosana (Hayata) F. G. Meyer. Diagnostic characters of adults and larvae of Jadera haematoloma are discussed. A review of its bionomics and a bibliography are provided. Initial observations on the populations in southern Taiwan are presented. The species is potentially invasive, and further extension of its range is anticipated in Southeast Asia.     

The genus Nelcyndana Stål (Hemiptera, Cicadidae, Taphurini) with description of three new species from Borneo

The type species of Nelcyndana, Nelcyndana tener (Stål, 1870) from the Philippines, is redescribed and illustrated. The taxonomic position of the genus Nelcyndana in the tribe Taphurini is discussed. Three new species from Borneo are described and illustrated: Nelcyndana borneensis sp. n., Nelcyndana vantoli sp. n., and Nelcyndana mulu sp. n. Distributions maps for the three Borneo species are presented and a key for the identification of the four Asian species of the genus is provided.     

Revision of fossil Metretopodidae (Insecta: Ephemeroptera) in Baltic amber – Part 2: Description of a new species of Metretopus Eaton, 1901

In the second part of the revision of fossil Metretopodidae, a new species of the genus Metretopus Eaton, 1901 is described and illustrated based on a male imago. Metretopus dividussp. nov. is the second fossil species of the genus. Distinguishing characters for its separation from other fossil and recent representatives of Metretopus are discussed. http://www.zoobank.org/urn:lsid:zoobank.org:act:BCC5CB69-8014-4DA1-A0DA-DCF714969081