Brachypterous Forms Research Articles

Functional characterization of five developmental signaling network genes in the white-backed planthopper: Potential application for pest management.

The white-backed planthopper (WBPH, Sogatella furcifera) is a major rice pest that exhibits condition dependent wing dimorphisms - a macropterous (long wing) form and a brachypterous (short wing) form. Although, the gene cascade that regulates wing development and dimorphic differentiation has been largely defined, the utility of these genes as targets for pest control has yet to be fully explored. Five genes typically associated with the developmental signaling network, armadillo (arm), apterous A (apA), scalloped (sd), dachs (d), and yorkie (yki) were identified from the WBPH genome and their roles in wing development assessed following RNA interference (RNAi)-mediated knockdown. At 5 days-post injection, transcript levels for all five targets were substantially decreased compared with the dsGFP control group. Among the treatment groups, those injected with dsSfarm had the most pronounced effects on transcript reduction, mortality (95 ± 3%), and incidence (45 ± 3%) of wing deformities, whereas those injected with dsSfyki had the lowest incidence (6.7 ± 4%). To assess the utility of topical RNAi for Sfarm, we used a spray-based approach that complexed a large-scale, bacteria-based double-stranded RNA (dsRNA) expression pipeline with star polycation (SPc) nanoparticles. Rice seedlings infested with third and fourth instar nymphs were sprayed with SPc-dsRNA formulations and RNAi phenotypic effects were assessed over time. At 2 days post-spray, Sfarm transcript levels decreased by 86 ± 9.5% compared with dsGFP groups, and the subsequent incidences of mortality and wing defects were elevated in the treatment group. This study characterized five genes in the WBPH developmental signaling cascade, assessed their impact on survival and wing development via RNAi, and developed a nanoparticle-dsRNA spray approach for potential field control of WBPH. © 2023 Society of Chemical Industry.

Identification and reproductive isolation of Euborellia species (Insecta, Dermaptera, Anisolabididae) from East and Southeast Asia.

Euborellia (Anisolabididae: Anisolabidinae) is one of the most speciose genera of earwigs (Dermaptera), and its species-level classification is difficult. To settle the classification of brachypterous species with abbreviated tegmina recorded from East and Southeast Asia, we examined the morphology and reproductive isolation of three tentative Euborellia species, and analyzed the DNA barcoding region of the mitochondrial cytochrome oxidase subunit I (COI) gene. The observed complete reproductive isolation among the three Euborellia taxa and considerable differentiation in the COI sequences clearly show that each should be treated as a separate species. Based on morphology, distribution and the DNA sequence, we identify Euborellia sp. 1 of Malaysia as E.annulata (Fabricius), a circumtropical cosmopolitan with no records of a fully winged form. Samples from Ioto Island (= Iwo-jima Island: Ogasawara Islands, southern Japan) were also identified as this species. Euborellia sp. 3, from the main islands of Japan, was generally larger and lacked a Y-shaped pigmented area on the penis lobe, which is characteristic of Euborellia sp. 1. We propose reinstating E.pallipes (Shiraki) as the oldest name for this taxon. Euborellia sp. 2, even the brachypterous form, can be distinguished from these two species by its paler coloration (particularly the femora), ecarinate post-abdomen, and the shape of the male genitalia (parameres). We tentatively identify this species as E.philippinensis Srivastava based on the morphology of the brachypterous form, although the macropterous form cannot be distinguished from E.femoralis (Dohrn).

Report on antennal sensilla of Aphelocheirus ellipsoideus (Hemiptera, Heteroptera, Aphelocheiridae).

The comparative morphology study on antennal sensilla of Aphelocheirus ellipsoideus from the family Aphelocheiridae, carried out with the use of a scanning electron microscope, is provided. Five main types of mechano-, chemo-, and thermo-hygroreceptive sensilla with two subtypes of sensilla basiconica were found and described on their surface, including sensilla trichodea, campaniformia, basiconica, ampullacea, and plate-like. Antennal sensilla of A. ellipsoideus on macropterous and brachypterous forms were different.

Intraspecific variation in the morphology of Alloxysta fracticornis (Thomson, 1862)(Hymenoptera: Figitidae: Charipinae)

ABSTRACT A new brachypterous form of Alloxysta fracticornis (Thomson, 1862) has been found in the Museum of Natural History of Wroclaw University (Poland). This is the first time that this morphological variation has been recorded for A. fracticornis. The morphological features of this new form match with this species, except for the wing length, which is characteristic of the brachypterous form, and the colour. COI sequences and phylogenetic analysis for the specimens studied (macropterous and brachypterous) confirm that the two morphologies belong to the same species, as we suspected a priori. Thus, in this study we show evidence of morphological variation in A. fracticornis, and demonstrate the value of studying entomological collections as well as new material to improve the taxonomic knowledge of this subfamily.

Synopsis of Incertosulcus Móczár, 1970 (Hymenoptera: Bethylidae)

ABSTRACT Since the original description of Incertosulcus Móczár, 1970 no species have been added to the genus, because of its unclarified taxonomic diagnostic characters. Herein we provide an emended diagnosis for this genus, describe and illustrate five new species, Incertosulcus pinotage sp. nov., I. pinotnoir sp. nov., I sauvignonblanc sp. nov., I. semillon sp. nov., and I. shiraz sp. nov., from Africa; and record for the first time a brachypterous form for the genus. We also transfer Incertosulcus ceylonicus (Móczár, 1979) to Heterocoelia Dahlbom, 1854. Additionally, we provide the first key for female and male species and a discussion about the main diagnostic characteristics of Incertosulcus Mórczár, 1970. http://www.zoobank.org/urn:lsid:zoobank.org:pub:C512C3A4-0E6C-4AE7-AA87-5A7D2794F445

Comparison of Frankliniella fusca and Frankliniella occidentalis (Thysanoptera: Thripidae) as Vectors for a Peanut Strain of Tomato Spotted Wilt Orthotospovirus.

Tomato spotted wilt orthotospovirus (TSWV) is a major disease in peanut, Arachis hypogaea L., across peanut producing regions of the United States and elsewhere. Two thrips, Frankliniella fusca Hinds and Frankliniella occidentalis Pergande (Thysanoptera: Thripidae), are considered important vectors of TSWV in peanut in the Southeast. We compared the efficiency of acquisition (by larvae) and transmission (adults) of both thrips species for TSWV (Texas peanut-strain) to leaf disks of peanut (Florunner), as well as to Impatiens walleriana Hook. f. (Dwarf White Baby) and Petunia hybrida Juss. 'Fire Chief' using double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). Both species were competent TSWV vectors in peanut and Impatiens, although F. fusca was the more efficient vector overall, i.e., virus acquisition and transmission rates for F. fusca averaged over several bioassays were 51.7 and 26.6%, respectively, compared with 20.0 and 15.3% for F. occidentalis. Neither species effectively transmitted this TSWV strain to Petunia (i.e., ≤3.6% transmission). We found statistically similar virus acquisition and transmission rates between both sexes for each species. We also detected no differences in TSWV-acquisition and transmission frequency between macropterous and brachypterous (short-wing) forms of F. fusca collected from a field population in south Texas. DAS-ELISA failed to detect low levels of TSWV in a few thrips that subsequently proved to be competent vectors.

The Brachypterous Ground-Litter-Inhabiting Species ofRhyopsocusHagen (Psocodea: ‘Psocoptera’: Trogiomorpha: Psoquillidae) from Southwestern United States, Mexico, and Guatemala, with Descriptions of Two New Species

ABSTRACT This work is aimed at the species-level identification of the brachypterous forms of the genus Rhyopsocus found primarily in ground litter throughout southwestern United States, Mexico, and Guatemala. Characters for separation of species used in the present study and in past studies are reviewed critically. A revised definition of Rhyopsocus is given, based in part on venation of macropterous forms. The structure of the complex Rhyopsocus phallosome is compared to that of the species of the genus Psoquilla Hagen. Two new species of Rhyopsocus are described, both from southwestern United States and known to extend into Mexico. The descriptions of Rhyopsocus maculosus Garcia Aldrete, Rhyopsocus micropterus Mockford, Rhyopsocus texanus (Banks) and Rhyopsocus concavus Garca Aldrete are augmented with some new characters. A key to the brachypterous forms of Rhyopsocus species occurring in the area under study is presented. The question of whether the species dealt with here form a clade within Rhyopso...

Cover Caption

Insect ScienceVolume 23, Issue 5 CONTENTSFree Access Cover Caption First published: 19 September 2016 https://doi.org/10.1111/1744-7917.12268AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract Snow cover is an important environmental component which facilitates migration and as a stage of sexual behaviour for some aquatic Chironomidae of a winter emerging strategy. A community of at least 35 species active on the snow was found during a long-term study of adult non-biting midges in temperate areas of Poland. The fully-wings as well as brachypterous forms were documented to swarm on the snow and use the searching mating behaviour within some narrow temperature range of mid and late winter. (See pages 754–770). Photo provided by Agnieszka SoszyDska-Maj. Volume23, Issue5October 2016 RelatedInformation

A taxonomic study of the genus Panesthia (Blattodea, Blaberidae, Panesthiinae) from China with descriptions of one new species, one new subspecies and the male of Panesthiaantennata.

One new species Panesthia guizhouensis sp. n. and one new subspecies Panesthia stellata concava ssp. n. are described and illustrated. The male of Panesthia antennata Brunner von Wattenwyl, 1893 and its brachypterous form are described and illustrated for the first time. Panesthia strelkovi Bey-Bienko, 1969 is redescribed and illustrated. Three known species, Panesthia birmanica Brunner von Wattenwyl, 1893, Panesthia sinuata Saussure, 1839 and Panesthia angustipennis cognata Bey-Bienko, 1969 are illustrated. In addition, a key to all species of the genus Panesthia from China is presented.

The genus Ctenothrips from India (Thysanoptera: Thripidae) with description of one new species and one new record.

Ctenothrips barapatharensis sp.n. is described from specimens collected on ferns from Himachal Pradesh state of India. This is the only species in this genus having dark thickenings attached to fore ocellus. Ctenothrips niger Kudô is newly recorded from India, and the brachypterous form is described for the first time. A key to the three species of Ctenothrips from India is provided.

The content of amino acids in artificial diet influences the development and reproduction of brown planthopper, Nilaparvata lugens (STÅL).

Nitrogen availability from dietary protein has profound effects on the physiology and ecology of insect herbivores. The amount of amino acids consumed by Nilaparvata lugens impacts its phenotypic characteristics and reproduction. In this work, we hypothesized that amino acids deficiency leads to physiological trade-offs between survival and reproduction. We investigated the effect of larval nutrition on larval period, wing dimorphism, egg production, ovarian development, lifespan, and stored nutrients. Larvae were reared on the standard medium and an amino acid deficient medium (AADM), adults were reared on the standard medium. Nymphs reared on AADM had shorter larval period (20.78 d/23.09 d), higher brachypterous forms (34.06%/16.52%), the adults females were fed back on standard medium after emergency, they featured extended preoviposition period (11.41/13.45 d), declining number of laid eggs (2.27/37.44), ovarian dysplasia, and shorter lifespan compared with control group. Adults from both dietary treatment groups had approximately the same proportion of total lipids and protein nutrients carried over from larvae feeding into adulthood. We infer that N. lugens makes a physiological trade-off between survival and reproduction by suppressing ovarian development. This is probably a common strategy during times of nutritional deficiency in nature.

A Global Perspective of Rice Brown Planthopper Management ?--Crop-Climatic Requirement

Rice Brown Planthopper, Nilaparvata lugens (Stal) (BPH) along with White-backed Planthopper, Sogatella furcifera (Horvath) (WBPH) have co-evolved along with rice plant during its domestication of thousands of years. These plant hoppers are small insects. The adults measure about 4-6 mm in length and 3-4 mm in width. The nymphs as well as adults suck plant sap from phloem and occasionally from xylem. Enormous draining of sap results in drying of plants in circular patches called “hopper-burn”. Adults have two morphologically distinct forms1) macropterous i.e. those with fully developed wings and 2) brachypterous i.e. those with half developed wings. Macropterous forms can move up to few thousands of kilometers and settle in favorable areas. The progeny develops into brachypterous forms capable of laying 300-400 eggs/female facilitating very rapid population build up. This process of morpho-form development is under hormonal regulation and genetically controlled. Distribution of BPH in the field is patchy or clumped i.e. “negative binomial distribution”. East Asian, South-east Asian, and South Asian biotypes of BPH with distinct virulence patterns for host resistance exist. Long range migration of East Asian biotype from southern tip of China to Japan and Korea and back has been well documented. Possibility of such migration in South Asian biotype from Sri Lanka up to Punjab is hypothesized. South-east Asian biotype can possibly move from Indo-China countries up to tip of Indonesia and back .

Flight initiation of Nysius huttoni (Hemiptera: Orsillidae) in relation to temperature and wing forms

Flight initiation of the New Zealand wheat bug, Nysius huttoni White, in relation to temperature and wing forms was studied in the field over a period of 4 years. The results indicated that temperature is a major factor affecting flight initiation of this species. When air temperature rose to 27 °C, and/or the ground temperature reached 40 °C, flights occurred. These two temperatures are determined as thresholds for flight initiation. Flights were short, low and hop-like, covering up to five metres. Flight behaviour is displayed by a portion of individuals of a population in response to high temperature, suggesting that other factors are involved. Flight can occur in adults of any generation except overwintered generation depending on ambient temperature, but mainly in those of second and third generations. Daytime flight is common, peaking especially around midday with high temperatures. Macropterous and sub-brachypterous forms are capable of flight, whereas the brachypterous form is apparently flightless. Both sexes of flying adults have the same temperature thresholds for flight.

Infection Rates and Comparative Population Dynamics ofPeregrinus maidis(Hemiptera: Delphacidae) on Corn Plants With and Without Symptoms of Maize Mosaic Virus (Rhabdoviridae: Nucleorhabdovirus) Infection

We examined the population dynamics of the corn planthopper Peregrinus maidis (Ashmead) (Hemiptera: Delphacidae) throughout a cycle of corn (Zea mays L.) production on plants with or without symptoms of maize mosaic virus (MMV) (Rhabdoviridae: Nucleorhabdovirus) infection. Our results indicate that the timing of MMV plant infection greatly influenced the planthopper's host plant colonization patterns. Corn plants that expressed symptoms of MMV infection early in the crop cycle (28 d after planting) harbored, on average, 40 and 48% fewer planthoppers than plants that expressed symptoms of MMV infection later in the crop cycle (49 d after planting) and asymptomatic plants, respectively. We also observed a change in the number of brachypterous (short-wing type) and macropterous (long-wing type) winged forms produced; plants expressing early symptoms of MMV infection harbored, on average, 41 and 47% more of the brachypterous form than plants with late infections of MMV and plants with no symptoms of MMV, respectively. Furthermore, we determined the rates of MMV-infected planthoppers relative to their wing morphology (macropterous or brachypterous) and gender. MMV infection was 5 and 12% higher in females than in males in field and greenhouse experiments, respectively; however, these differences were not significantly different. This research provides evidence that MMV similarly infects P. maidis planthoppers regardless of the gender and wing morphotype. These results also suggest that the timing of symptom development greatly affects the population dynamics of the planthopper vector, and likely has important consequences for the dynamics of the disease in the field.

On some brachypterous Encyrtidae (Hymenoptera: Chalcidoidea) from India, with description of four new species

Four new species of brachypterous Encyrtidae (Hymenoptera: Chalcidoidea) are described. These are: Cheiloneurus mandyanus Hayat, sp. nov., Encyrtus coorgensis Hayat & Zeya, sp. nov., Microterys atturensis Hayat, sp. nov. and Pseudectroma indicum Hayat & Zeya, sp. nov. The following species that exist either in brachypterous forms only or in both brachypterous and macropterous forms are recorded: Anomalicornia tenuicornis Mercet, Cheiloneurus bangalorensis (Subba Rao), C. quadricolor (Girault), Diversinervus cervantesi (Girault), Globulencyrtus politus (Hoffer), Indaphycus planus Hayat, Neodusmetia sangwani (Subba Rao), Prochiloneurus bolivari Mercet, Rhopus atys Noyes & Hayat and Sakencyrtus mirus Hayat. Globulencyrtus politus and P bolivari are newly recorded from India. A diagnosis of Globulencyrtus, and redescriptions of G politus, P bolivari based on the Indian specimens and of the brachypterous forms of R. atys are given. The occurrence of brachyptery in the Encyrtidae is briefly noted together with a list of brachypterous species recorded from India.

The peculiar winter-active midge Diamesa starmachi (Diptera: Chironomidae)

ABSTRACT Morphological variations in brachypterous and fully-winged forms of Diamesa starmachi KOWNACKI et KOWNACKA, 1970, including the first description of the female, are presented. Notes on the biology of this winter-active chironomid, based on new data from Poland, are also provided.

Temperature-dependent wing dimorphism in a Japanese strain of tobacco thrips, Frankliniella fusca (Thysanoptera: Thripidae)

A Japanese strain of Frankliniella fusca (Hinds) was reared under 4 temperature and two photoperiodic conditions on leaves of green bean. On the basis of the ratio of fore wing length to head width (RWL) of adult thrips we defined individuals with RWL above 3.7 as macropterous forms and those with RWL below 3.5 as brachypterous forms. Percentages of macropterous individuals among females were 0 % at 18 °C, 10.6 % at 22.5 °C, 21.8 % at 25 °C, and 77.5 % at 27.5 °C, under 15L–9D. The proportion of macropters among females developing under 15L–9D was no different from that among those developing under 10L–14D. These results indicate that photoperiod does not affect wing form, and suggest that the proportion of macropterous females increases with temperature. Although development time from hatching to adult eclosion, adult pre-oviposition period, adult head width, adult longevity, total fecundity, and fecundity schedule were compared between macropterous and brachypterous females developing at 25 °C and 15L–9D, these traits were not significantly different between the wing forms. Males of this experimental strain were all brachypterous.

A remarkable new genus of Dikraneurini (Hemiptera: Cicadomorpha: Cicadellidae: Typhlocybinae) from Southeast Asia

Sweta gen. n. is described and illustrated based on type species S. hallucinata sp. n. from northeast India and Thailand and placed in the typhlocybine tribe Dikraneurini. The new genus is unique among known Typhlocybinae in having the pronotum enlarged and extended to the scutellar suture. This feature is characteristic of the related subfamily Signoretiinae, but among other subfamilies is restricted to a few brachypterous forms.

A new species of Martarega White, 1879 from South America (Hemiptera: Heteroptera: Notonectidae), with an identification key to all described species of the genus

Martarega guarani sp. n. is described and illustrated from north-eastern Argentina (Misiones Province), based on brachypterous forms of both sexes and macropterous females. Comparisons with its close relative M. uruguayensis are included. The hind femur with a basal notch extending some distance beyond the apex of the trochanter and conspicuous enlargement contiguous to this notch distinguish the female of M. guarani sp. n. from those of all the remaining species of Martarega. The following combination of characters distinguish the male of M. guarani sp. n. from those of all the remaining species of Martarega: total body length less than 6.5 mm; metaxyphus trilobed with median lobe bluntly rounded; hemelytra of brachypterous form opaque with a narrow straight hyaline stripe running medially almost entire length of wing and a second short one at base of the hemelytral process; anterior surface of middle trochanter with a group of cohesive lanceolate setae on a nodule; anterior surface of middle femur without a nodule. An identification key to the brachypterous form of all described species of Martarega is given. The distribution, habitat preferences and association between species of M. guarani sp. n. are presented.

Psoquilla infuscata Badonnel (Psocoptera: Psoquillidae) in the Western Hemisphere with description of the male and brachypterous form

Psoquilla infuscata Badonnel (Psocoptera: Psoquillidae) in the Western Hemisphere with description of the male and brachypterous form