240 research outputs found

    Wireless Stimulation of Antennal Muscles in Freely Flying Hawkmoths Leads to Flight Path Changes

    Get PDF
    Insect antennae are sensory organs involved in a variety of behaviors, sensing many different stimulus modalities. As mechanosensors, they are crucial for flight control in the hawkmoth Manduca sexta. One of their roles is to mediate compensatory reflexes of the abdomen in response to rotations of the body in the pitch axis. Abdominal motions, in turn, are a component of the steering mechanism for flying insects. Using a radio controlled, programmable, miniature stimulator, we show that ultra-low-current electrical stimulation of antennal muscles in freely-flying hawkmoths leads to repeatable, transient changes in the animals' pitch angle, as well as less predictable changes in flight speed and flight altitude. We postulate that by deflecting the antennae we indirectly stimulate mechanoreceptors at the base, which drive compensatory reflexes leading to changes in pitch attitude.United States. Defense Advanced Research Projects Agenc

    First records of two mealybug species in Brazil and new potential pests of papaya and coffee

    Get PDF
    Five mealybug (Hemiptera: Pseudococcidae) plant pest species: Dysmicoccus grassii (Leonardi), Ferrisia malvastra (McDaniel), Ferrisia virgata (Cockerell), Phenacoccus tucumanus Granara de Willink, and Pseudococcus elisae Borchsenius are recorded for the first time in the state of EspĂ­rito Santo, Brazil. These are the first records of D. grassii in Brazil, from papaya (Carica papaya, Caricaceae), and from coffee (Coffea canephora, Rubiaceae). Ferrisia malvastra is also newly recorded in Brazil, where it was found on Bidens pilosa (Asteraceae). Ferrisia virgata was collected from an unidentified weed and Phenacoccus tucumanus from Citrus sp. (Rutaceae). Plotococcus capixaba Kondo was found on pitanga (Eugenia cf. pitanga, Myrtaceae) and Pseudococcus elisae on Coffea canephora, which are new host records for these mealybugs

    Anti-cancer effects and mechanism of actions of aspirin analogues in the treatment of glioma cancer

    Get PDF
    INTRODUCTION: In the past 25 years only modest advancements in glioma treatment have been made, with patient prognosis and median survival time following diagnosis only increasing from 3 to 7 months. A substantial body of clinical and preclinical evidence has suggested a role for aspirin in the treatment of cancer with multiple mechanisms of action proposed including COX 2 inhibition, down regulation of EGFR expression, and NF-ÎșB signaling affecting Bcl-2 expression. However, with serious side effects such as stroke and gastrointestinal bleeding, aspirin analogues with improved potency and side effect profiles are being developed. METHOD: Effects on cell viability following 24 hr incubation of four aspirin derivatives (PN508, 517, 526 and 529) were compared to cisplatin, aspirin and di-aspirin in four glioma cell lines (U87 MG, SVG P12, GOS – 3, and 1321N1), using the PrestoBlue assay, establishing IC50 and examining the time course of drug effects. RESULTS: All compounds were found to decrease cell viability in a concentration and time dependant manner. Significantly, the analogue PN517 (IC50 2mM) showed approximately a twofold increase in potency when compared to aspirin (3.7mM) and cisplatin (4.3mM) in U87 cells, with similar increased potency in SVG P12 cells. Other analogues demonstrated similar potency to aspirin and cisplatin. CONCLUSION: These results support the further development and characterization of novel NSAID derivatives for the treatment of glioma

    Spatiotemporal trends in cetacean strandings and response in the southwestern Indian Ocean : 2000–2020

    Get PDF
    On behalf of SIF, we would like to thank the Seychelles partners (Alphonse Foundation, Desroches Foundation, Island Conservation Society, Farquhar Foundation, Seychelles Islands Foundation, Silhouette Foundation) for providing financial support to acquire and grant use of their data. Collection of data in Reunion was funded by DEAL Reunion and Region-Reunion.The south-western Indian Ocean (SWIO) is a region of global importance for marine mammal biodiversity, but our understanding of most of the species and populations found there is still rudimentary. The Indian Ocean Network for Cetacean Research (IndoCet) was formed in 2014 and is dedicated to the research of all cetacean species across the SWIO. Since 2019, there have been efforts to create a regional network for coordinated response to stranding events as well as training and capacity building in the SWIO region. The present analysis represents a first investigation of stranding data collected by various members and collaborators within the IndoCet network, covering over 14,800km of coastline belonging to nine countries/territories. Between 2000–2020, there were 397 stranding events, representing 1,232 individual animals, 17 genera and 27 species, belonging to six families: four balaenopterids, one balaenid, one physeterid, two kogiids, six ziphiids and 14 delphinids. Seven mass strandings were recorded: two were composed of three to 20 individuals and five composed of > 20 individuals. Spatial analysis of stranding events indicated that local spatio-temporal clusters (excessive number of events in time and geographic space) were present in all countries/territories, except for the Comoros. The only significant cluster was detected on the southwest coast of Mauritius, just west of the village of Souillac. The SWIO region predominantly comprises relatively poor countries/territories, but imminent Ocean Economy developments are prevalent throughout the region. This study highlights the importance of establishing baselines upon which any future potential impact from anthropogenic developments in the region can be measured.Peer reviewe

    Mechanosensory interactions drive collective behaviour in Drosophila.

    Get PDF
    Collective behaviour enhances environmental sensing and decision-making in groups of animals. Experimental and theoretical investigations of schooling fish, flocking birds and human crowds have demonstrated that simple interactions between individuals can explain emergent group dynamics. These findings indicate the existence of neural circuits that support distributed behaviours, but the molecular and cellular identities of relevant sensory pathways are unknown. Here we show that Drosophila melanogaster exhibits collective responses to an aversive odour: individual flies weakly avoid the stimulus, but groups show enhanced escape reactions. Using high-resolution behavioural tracking, computational simulations, genetic perturbations, neural silencing and optogenetic activation we demonstrate that this collective odour avoidance arises from cascades of appendage touch interactions between pairs of flies. Inter-fly touch sensing and collective behaviour require the activity of distal leg mechanosensory sensilla neurons and the mechanosensory channel NOMPC. Remarkably, through these inter-fly encounters, wild-type flies can elicit avoidance behaviour in mutant animals that cannot sense the odour--a basic form of communication. Our data highlight the unexpected importance of social context in the sensory responses of a solitary species and open the door to a neural-circuit-level understanding of collective behaviour in animal groups

    Temporal variation in sex allocation in the mealybug <em>Planococcus citri</em>:Adaptation, constraint, or both?

    Get PDF
    Sex ratio theory has been very successful in predicting under which circumstances parents should bias their investment towards a particular offspring sex. However, most examples of adaptive sex ratio bias come from species with well-defined mating systems and sex determining mechanisms, while in many other groups there is still an on-going debate about the adaptive nature of sex allocation. Here we study the sex allocation in the mealybug Planococcus citri, a species in which it is currently unclear how females adjust their sex ratio, even though experiments have shown support for facultative sex ratio adjustment. Previous work has shown that the sex ratio females produce changes over the oviposition period, with males being overproduced early and late in the laying sequence. Here we investigate this complex pattern further, examining both the robustness of the pattern and possible explanations for it. We first show that this sex allocation behaviour is indeed consistent across lines from three geographical regions. Second, we test whether females produce sons first in order to synchronize reproductive maturation of her offspring, although our data provide little evidence for this adaptive explanation. Finally we test the age at which females are able to mate successfully and show that females are able to mate and store sperm before adult eclosion. Whilst early-male production may still function in promoting protandry in mealybugs, we discuss whether mechanistic constraints limit how female allocate sex across their lifetime

    Genomic changes associated with the evolutionary transition of an insect gut symbiont into a blood-borne pathogen.

    Get PDF
    The genus Bartonella comprises facultative intracellular bacteria with a unique lifestyle. After transmission by blood-sucking arthropods they colonize the erythrocytes of mammalian hosts causing acute and chronic infectious diseases. Although the pathogen-host interaction is well understood, little is known about the evolutionary origin of the infection strategy manifested by Bartonella species. Here we analyzed six genomes of Bartonella apis, a honey bee gut symbiont that to date represents the closest relative of pathogenic Bartonella species. Comparative genomics revealed that B. apis encodes a large set of vertically inherited genes for amino acid and cofactor biosynthesis and nitrogen metabolism. Most pathogenic bartonellae have lost these ancestral functions, but acquired specific virulence factors and expanded a vertically inherited gene family for harvesting cofactors from the blood. However, the deeply rooted pathogen Bartonella tamiae has retained many of the ancestral genome characteristics reflecting an evolutionary intermediate state toward a host-restricted intraerythrocytic lifestyle. Our findings suggest that the ancestor of the pathogen Bartonella was a gut symbiont of insects and that the adaptation to blood-feeding insects facilitated colonization of the mammalian bloodstream. This study highlights the importance of comparative genomics among pathogens and non-pathogenic relatives to understand disease emergence within an evolutionary-ecological framework

    Comparative morphology of the forewing base articulationin Sternorrhyncha compared with a representative of Fulgoromorpha (Insecta, Hemiptera)

    Get PDF
    The forewing articulation of single species from each of the four subgroups of Sternorrhyncha (Aleyrodomorpha, Aphidomorpha, Coccomorpha, Psyllomorpha) was examined by optical and scanning electron microscopy. The species were compared with a species of Cixiidae (Fulgoromorpha), as an outgroup of Sternorrhyncha. We present the results of a comparative analysis of the forewing articulation in these five groups, propose a standardized terminology and compare our findings with those previously reported. The wing base of all examined species is composed of the following structures: anterior and posterior notal wing process, first, second, and third axillary sclerites, tegula, and axillary cord. The number of elements included in the wing base and the surrounding area is the greatest in Cacopsylla mali, the most complicated species from Sternorrhyncha. Based on the shape of axillary sclerites and the number of elements forming the wing base environment, Orthezia urticae (Coccomorpha) and Cixius nervosus (Fulgoromorpha) are the most similar. Among Sternorrhyncha, the most similar axillaries are those of Aphis fabae and Orthezia urticae, which is congruent with existing classifications. In this paper we show that the four groups from Sternorrhyncha exhibit their own distinct wing base morphology

    How a slow-ovipositing parasitoid can succed as a biological control agent of the invasive mealybug Phenacoccus peruvianus: implications for future classical and conservation biological control programs

    Full text link
    [EN] Phenaccocus peruvianus Granara de Willink (Hemiptera: pseudococcidae) is an invasive mealybug that has become a pest of ornamental plants in Europe and has recently been detected in California, USA. In this work, we studied the tritrophic interaction among this mealybug, its main parasitoid Acerophagus n. sp. near coccois (Hymenoptera: Encyrtidae) and tending ants to disclose the success of this parasitoid controlling P. peruvianus. Acerophagus n. sp. near coccois accepted mealybugs for parasitism regardless of their size but did not hostfeed. We recorded three active defenses of P. peruvianus. Host handling time-consuming process that required more than 30 min. Tending ants, Lasius grandis (Hymenoptera: Encyrtidae), reduced the time spent by parasitoids in a patch and disrupted oviposition attempts. The low numbers of ants tending mealybugs colonies in Spain and France could explain why this parasitoid, with a long handling time, is an efficient biological control agent for P. peruvianus.BeltrĂ  Ivars, A.; Soto SĂĄnchez, AI.; Tena Barreda, A. (2015). How a slow-ovipositing parasitoid can succed as a biological control agent of the invasive mealybug Phenacoccus peruvianus: implications for future classical and conservation biological control programs. BioControl. 60(4):473-484. https://doi.org/10.1007/s10526-015-9663-6S473484604Arakelian G (2013) Bougainvillea mealybug (Phenacoccus peruvianus). Factsheet 2013. County of Los Angeles. Department of agricultural commissioner/weights and measures, USABartlett BR (1961) The influence of ants upon parasites, predators, and scale insects. Ann Entomol Soc Am 54:543–551Bartlett BR (1978) Pseudococcidae. In: Clausen CP (ed) Introduced parasites and predators of arthropod pests and weeds: a world review, 1st edn. Agricultural Research Service USDA, Washington, USA, pp 137–170Barzman MS, Daane KM (2001) Host-handling behaviors in parasitoids of black scale, Saissetia oleae (Homoptera: Coccidae): a case for ant-mediated evolution. J Anim Ecol 70:237–247BeltrĂ  A, Soto A, Germain JF, Matile-Ferrero D, Mazzeo G, Pellizzari G, Russo A, Franco JC, Williams DJ (2010) The Bougainvillea mealybug Phenacoccus peruvianus, a rapid invader from South America to Europe. Entomol Hell 19:137–143BeltrĂ  A, Garcia-MarĂ­ F, Soto A (2013a) Seasonal phenology, spatial distribution, and sampling plan for the invasive mealybug Phenacoccus peruvianus (Hemiptera: Pseudococcidae). J Econ Entomol 106:1486–1494BeltrĂ  A, Tena A, Soto A (2013b) Fortuitous biological control of the invasive mealybug Phenacoccus peruvianus in Southern Europe. BioControl 58:309–317BeltrĂ  A, Tena A, Soto A (2013c) Reproductive strategies and food sources used by Acerophagus n. sp. near coccois, a new successful parasitoid of the invasive mealybug Phenacoccus peruvianus. J Pest Sci 86:253–259Berlinger MJ, Golberg AM (1978) The effect of the fruit sepals on the citrus mealybug population and on its parasite. Entomol Exp Appl 24:238–243Blumstein DT, Daniel JC (2007) Quantifying behavior the JWatcher way. Sinauer Associates Inc., Sunderland, UKBoavida C, Ahounou M, Vos M, Neuenschwander P, van Alphen JJM (1995) Host stage selection and sex allocation by Gyranusoidea tebygi (Hymenoptera: Encyrtidae), a parasitoid of the mango mealybug, Rastrococcus invadens (Homoptera: Pseudococcidae). Biol Control 5:487–496Bokonon-Ganta AH, Neuenschwander P, van Alphen JJM, Vos M (1995) Host stage selection and sex allocation by Anagyrus mangicola (Hymenoptera: Encyrtidae), a parasitoid of the mango mealybug, Rastrococcus invadens (Homoptera: Pseudococcidae). Biol Control 5:479–486Bugila AAA, Franco JC, Borges da Silva E, Branco M (2014a) Defense response of native and alien mealybugs (Hemiptera: Pseudococcidae) against the solitary parasitoid Anagyrus sp. nr. pseudococci (Girault) (Hymenoptera: Encyrtidae). J Insect Behav 27:439–453Bugila AAA, Branco M, Borges da Silva E, Franco JC (2014b) Host selection behavior and specificity of the solitary parasitoid of mealybugs Anagyrus sp. nr. pseudococci (Girault) (Hymenoptera, Encyrtidae). Biocontrol Sci Techn 24:22–38Bynum EK (1937) Pseudococcobius terryi Fullaway, a Hawaiian parasite of Gray Sugarcane mealybug in the United States. J Econ Entomol 30:756–761CadĂ©e N, van Alphen JJM (1997) Host selection and sex allocation in Leptomastidea abnormis, a parasitoid of the citrus mealybug Planococcus citri. Entomol Exp Appl 83:277–284Clausen CP (1924) The parasites of Pseudococcus maritimus (Ehrhorn) in California (Hymenoptera, Chalcidoidea). Part II. Biological studies and life histories. UC Pub Entomol 3:253–288Daane KM, Barzman MS, Caltagirone LE, Hagen KS (2000) Metaphycus anneckei and Metaphycus hageni: two discrete species parasitic on black scale, Saissetia oleae. BioControl 45:269–284Daane KM, Bentley WJ, Walton VM, Malakar-Kuenen R, Millar JC, Ingels CA, Weber EA, Gispert C (2006) New controls investigated for vine mealybug. Calif Agric 60:31–38Daane KM, Sime KR, Fallon J, Cooper ML (2007) Impacts of Argentine ants on mealybugs and their natural enemies in California’s coastal vineyards. Ecol Entomol 32:583–596De Farias AM, Hopper KR (1999) Oviposition behavior of Aphelinus asychis (Hymenoptera: Aphelinidae) and Aphidius matricariae (Hymenoptera: Aphidiidae) and defense behavior of their host Diuraphis noxia (Homoptera: Aphididae). Environ Entomol 28:858–862Dorn B, Mattiacci L, Bellotti AC, Dorn S (2001) Host specificity and comparative foraging behavior of Aenasius vexans and Acerophagus coccois, two endo-parasitoids of the cassava mealybug. Entomol Exp Appl 99:331–339Eisner T, Silberglied RE (1988) A chrysopid larva that cloaks itself in mealybug wax. Psyche 95:15–20Flanders SE (1963) Predation by parasitic Hymenoptera, the basis of ant-induced outbreaks of a host species. J Econ Entomol 56:116Foldi I (1983) Structure et fonctions des glandes tĂ©gumentaires de cochenilles Pseudococcines et de leurs secretions. Ann Soc Entomol Fr 19:155–156Foldi I (1997) Defense strategies in scale insects: phylogenetic inference and evolutionary scenarios (Hemiptera, Coccoidea). In: Grandcolas P (ed) The origin of biodiversity in insects: phylogenetic tests of evolutionary scenarios, 1st edn. MusĂ©um National d’Histoire Naturelle, Paris, France, pp 203–230Godfray HCJ (1994) Parasitoids: behavioral and evolutionary ecology. Princeton University Press, Princeton, USAGonzĂĄlez-HernĂĄndez H, Johnson MW, Reimer NJ (1999) Impact of Pheidole megacephala (F.) (Hymenoptera: Formicidae) on the biological control of Dysmicoccus brevipes (Cockerell) (Homoptera: Pseudococcidae). Biol Control 15:145–152Gross P (1993) Insect behavioral and morphological defenses against parasitoids. Annu Rev Entomol 38:251–273Gullan PJ (1997) Relationships with ants. In: Ben-Dov Y, Hodgson CJ (eds) Soft scale insects—their biology natural enemies and control, 1st edn. Elsevier, Amsterdam, The Netherlands, pp 351–373Gullan PJ, Kosztarab M (1997) Adaptations in scale insects. Annu Rev Entomol 42:23–50Hcidari M, Jahan M (2000) A study of ovipositional behavior of Anagyrus pseudococci a parasitoid of mealybugs. J Agric Sci Technol 2:49–53Honda JY, Luck RF (1995) Scale morphology effects on feeding behavior and biological control potential of Rhyzobius lophanthae (Coleoptera: Coccinellidae). Ann Entomol Soc Am 88:441–450Joyce AL, Hoddle MS, Bellows TS, Gonzalez D (2001) Oviposition behavior of Coccidoxenoides peregrinus, a parasitoid of Planococcus ficus. Entomol Exp Appl 98:49–57Karamaouna F (1999) Biology of the parasitoids Leptomastix epona (Walker) and Pseudaphycus flavidulus (BrĂšthes) and behavioural interactions with the host mealybug Pseudococcus viburni (Signoret). Ph.D. Thesis, University of London, UK, p 333Karamaouna F, Copland MJ (2000) Oviposition behavior, influence of experience on host size selection, and niche overlap of the solitary Leptomastix epona and the gregarious Pseudaphycus flavidulus, two endoparasitoids of the mealybug Pseudococcus viburni. Entomol Exp Appl 97:301–308Klotz JH, Hansen L, Pospischil R, Rust M (2008) Urban ants of North America and Europe. Cornell University Press, Ithaca, USAMailleux AC, Deneubourg JL, Detrain C (2003) Regulation of ants foraging to resource productivity. P R Soc Lond B Bio 270:1609–1616Majerus ME, Sloggett JJ, Godeau JF, Hemptinne JL (2007) Interactions between ants and aphidophagous and coccidophagous ladybirds. Popul Ecol 49:15–27Mgocheki N, Addison P (2009) Interference of ants (Hymenoptera: Formicidae) with biological control of the vine mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae). Biol Control 49:180–185Moore D (1988) Agents used for biological control of mealybugs (Pseudococcidae). Biocontrol News Inf 9:209–225Paris CI, Espadaler X (2009) Honeydew collection by the invasive garden ant Lasius neglectus versus the native ant L grandis. Arthropod Plant Interact 3:75–85Pekas A, Tena A, Aguilar A, Garcia-MarĂ­ F (2011) Spatio-temporal patterns and interactions with honeydew-producing Hemiptera of ants in a Mediterranean citrus orchard. Agric Forest Entomol 13:89–97Pennacchio F, Strand MR (2006) Evolution of developmental strategies in parasitic Hymenoptera. Annu Rev Entomol 51:233–258Pijls JW, Hofker KD, Staalduinen MJ, van Alphen JJM (1995) Interspecific host discrimination and competition in Apoanagyrus (Epidinocarsis) lopezi and A(E) diversicornis parasitoids of the cassava mealybug Phenacoccus manihoti. Ecol Entomol 20:326–332Robert Y (1987) Dispersion and migration. In: Minks AK, Harrewijn P (eds) Aphids—their biology, natural enemies and control, 1st edn. Elsevier, Amsterdam, The Netherlands, pp 299–313Sandanayaka WRM, Charles JG, Allan DJ (2009) Aspects of the reproductive biology of Pseudaphycus maculipennis (Hym: Encyrtidae), a parasitoid of obscure mealybug, Pseudococcus viburni (Hem: Pseudococcidae). Biol Control 48:30–35Sarkar D (2008) Lattice: multivariate data visualization with R. Springer, New York, USASime KR, Daane KM (2014) Rapid, non-discriminatory oviposition behaviors are favored in mealybug parasitoids when Argentine ants are present. Environ Entomol 43:995–1002Tena A, Garcia-MarĂ­ F (2008) Suitability of citricola scale Coccus pseudomagnoliarum (Hemiptera: Coccidae) as host of Metaphycus helvolus (Hymenoptera: Encyrtidae): Influence of host size and encapsulation. Biol Control 46:341–347Tena A, Hoddle CD, Hoddle MS (2013) Competition between honeydew producers in an ant–hemipteran interaction may enhance biological control of an invasive pest. Bull Entomol Res 103:714–723The R Core Team (2011) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austriavan Driesche RG, Belloti A, Herrera CJ, Castello JA (1987a) Host preferences of two encyrtid parasitoids for the Columbian Phenacoccus spp. of cassava mealybugs. Entomol Exp Appl 43:261–266van Driesche RG, Belloti A, Herrera CJ, Castello JA (1987b) Host feeding and ovipositor insertion as sources of mortality in the mealybug Phenacoccus herreni caused by two encyrtids Epidinocarsis diversicornis and Acerophagus coccois. Entomol Exp Appl 44:97–100Vet LE, Dicke M (1992) Ecology of infochemical use by natural enemies in a tritrophic context. Annu Rev Entomol 37:141–172Völkl W, Woodring J, Fischer M, Lorenz MW, Hoffmann KH (1999) Ant-aphid mutualisms: the impact of honeydew production and honeydew sugar composition on ant preferences. Oecologia 118:483–491Wajnberg E (1989) Analysis of variations of handling-time in Trichogramma maidis. Entomophaga 34:397–407Way MJ (1963) Mutualism between ants and honeydew-producing Homoptera. Annu Rev Entomol 8:307–344Weiss MR (2006) Defecation behavior and ecology of insects. Annu Rev Entomol 51:635–661Wyckhuys KAG, Stone L, Desneux N, Hoelmer KA, Hopper KR, Heimpel GE (2008) Parasitism of the soybean aphid Aphis glycines by Binodoxys communis: the role of aphid defensive behavior and parasitoid reproductive performance. Bull Entomol Res 98:361–370Zain-ul-Abdin, Arif MJ, Suhail A, Gogi MD, Arshad M, Wakil W, Abbas SK, Altaf A, Shaina H, Manzoor A (2012) Molecular analysis of the venom of mealybug parasitoid Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae). Pak Entomol 34:189–193Zinna G (1959) Specializzazione entomoparassitica negli Encyrtidae: studio morfologico etologico e fisiologico del Leptomastix dactylopii. Howard Boll Lab agr Filippo Silvestri 18:1–14
    • 

    corecore