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Graphical abstract Highlights • Fusarium solani significantly recruits Steinernema diaprepesi infective juveniles. • F. solani increases the insecticidal efficiency of S. diaprepesi. • Population of F. solani increases in soil where insect was killed by S. diaprepesi. • F. solani potentially develops in a mutualism with S. diaprepesi. Abstract In two field surveys, high proportions of Galleria mellonella L. (Lepidoptera: Pyralidae) sentinel larval cadavers were infected by Fusarium solani without evidence of concomitant entomopathogenic nematode (EPN) or entomopathogenic fungus (EPF) reproduction. Because F. solani is not considered entomopathogenic, the survey suggested the possibility that F. solani competes with EPNs. We tested the hypotheses that F. solani attracts the EPN, Steinernema diaprepesi , to facilitate infection of Diaprepes root weevils (Diaprepes abbreviatus L.) and thereafter competes with the nematode in the insect cadaver. In two-choice olfactometer assays where one side was treated with F. solani mycelia and conidia, juvenile S. diaprepesi were attracted to the fungus, in either raw soil, or in autoclaved soil in the presence or absence of insects. However, this attraction was attenuated as the habitat became more complex, by using raw soil in combination with insect larvae. Fusarium oxysporum did not recruit the nematode. When soil microcosms were tested with F. solani conidia and S. diaprepesi , the concomitant infection increased the mortality of the insect (P = 0.02) to 83%, compared to 58% and 0% mortality when nematodes or fungi were individually applied, respectively. Concomitant inoculation also increased the number of cadavers that supported nematode reproduction and increased the population density of fungus in soil. The number of IJs entering the host insect was not affected by F. solani. These results support the possibility that F. solani can facilitate the insecticidal efficiency of S. diaprepesi in order to exploit the resources in the cadaver. [ABSTRACT FROM AUTHOR]

Background: Male and female tsetse flies feed exclusively on vertebrate blood. While doing so they can transmit the diseases of sleeping sickness in humans and nagana in domestic stock. Knowledge of the host-orientated behavior of tsetse is important in designing bait methods of sampling and controlling the flies, and in understanding the epidemiology of the diseases. For this we must explain several puzzling distinctions in the behavior of the different sexes and species of tsetse. For example, why is it that the species occupying savannahs, unlike those of riverine habitats, appear strongly responsive to odor, rely mainly on large hosts, are repelled by humans, and are often shy of alighting on baits? Methodology/Principal Findings: A deterministic model that simulated fly mobility and host-finding success suggested that the behavioral distinctions between riverine, savannah and forest tsetse are due largely to habitat size and shape, and the extent to which dense bushes limit occupiable space within the habitats. These factors seemed effective primarily because they affect the daily displacement of tsetse, reducing it by up to ∼70%. Sex differences in behavior are explicable by females being larger and more mobile than males. Conclusion/Significance: Habitat geometry and fly size provide a framework that can unify much of the behavior of all sexes and species of tsetse everywhere. The general expectation is that relatively immobile insects in restricted habitats tend to be less responsive to host odors and more catholic in their diet. This has profound implications for the optimization of bait technology for tsetse, mosquitoes, black flies and tabanids, and for the epidemiology of the diseases they transmit. [ABSTRACT FROM AUTHOR]

Vannella sp. isolated from waterweed Elodea sp. was found infected by a chlamydia-like organism. This organism behaves like a parasite, causing the death through burst of its host. Once the vannellae degenerated, the parasite was successfully kept in laboratory within a Saccamoeba sp. isolated from the same waterweed sample, which revealed in fine through electron microscopy to harbor two bacterial endosymbionts: the chlamydial parasite we introduce and another endosymbiont initially and naturally present in the host. Herein, we provide molecular-based identification of both the amoeba host and its two endosymbionts, with special focus on the chlamydia parasite. High sequence similarity values of the 18S rDNA permitted to assign the amoeba to the species Saccamoeba lacustris (Amoebozoa, Tubulinea). The bacterial endosymbiont naturally harbored by the host belonged to Sphingomonas koreensis (Alpha-Proteobacteria). The chlamydial parasite showed a strict specificity for Saccamoeba spp., being unable to infect a variety of other amoebae, including Acanthamoeba, and it was itself infected by a bacteriophage. Sequence similarity values of the 16S rDNA and phylogenetic analysis indicated that this strain is a new member of the family Parachlamydiaceae, for which we propose the name ' Candidatus Mesochlamydia elodeae.' [ABSTRACT FROM AUTHOR]

Fungivorous tenebrionids, Ischnodactylus parallelicornis (Nakane 1956) and Platydema higonium Lewis, 1894 in the tribe Diaperini (Coleoptera: Tenebrionidae: Diaperinae), are recorded for the first time from Korea. Both I. parallelicornis and P. higonium are rare inhabitants of fungi on deciduous trees in Korea. These species all exhibit monophagy, with I. parallelicornis only inhabiting the fruiting body of Tramates orientalis and P. higonium only inhabiting the fruiting body of Stereum hirsutum and Stereum ostrea throughout their lives. A description, key to the Korean Ischnodoctylus and Platydema, fungal hosts, biological notes, photographs of adults and illustrations of diagnostic characteristics are provided herein. [ABSTRACT FROM AUTHOR]

Summary Xenorhabdus bovienii (SS-2004) bacteria reside in the intestine of the infective-juvenile (IJ) stage of the entomopathogenic nematode, Steinernema jollieti. The recent sequencing of the X. bovienii genome facilitates its use as a model to understand host - symbiont interactions. To provide a biological foundation for such studies, we characterized X. bovienii in vitro and host interaction phenotypes. Within the nematode host X. bovienii was contained within a membrane bound envelope that also enclosed the nematode-derived intravesicular structure. Steinernema jollieti nematodes cultivated on mixed lawns of X. bovienii expressing green or DsRed fluorescent proteins were predominantly colonized by one or the other strain, suggesting the colonizing population is founded by a few cells. Xenorhabdus bovienii exhibits phenotypic variation between orange-pigmented primary form and cream-pigmented secondary form. Each form can colonize IJ nematodes when cultured in vitro on agar. However, IJs did not develop or emerge from Galleria mellonella insects infected with secondary form. Unlike primary-form infected insects that were soft and flexible, secondary-form infected insects retained a rigid exoskeleton structure. Xenorhabdus bovienii primary and secondary form isolates are virulent towards Manduca sexta and several other insects. However, primary form stocks present attenuated virulence, suggesting that X. bovienii, like Xenorhabdus nematophila may undergo virulence modulation. [ABSTRACT FROM AUTHOR]

Some parasitic hymenopterans were reared from their host insects found on the stems and branches of Heracleum platytaenium Boiss., which contains furanocoumarins that are insect repellents and suppress growth in some species. Plant materials with insects were collected from the vicinity of Kızılcahamam in Ankara Province in July-September 2008. The parasitoids (Hymenoptera) and their hosts were Didyctium brunnea (Belizin) (Eucolidae) from puparia of Lasiambia albidipennis (Strobl) (Diptera: Chloropidae), Pronotalia carlinarum (Szelenyi & Erdos) (Eulophidae) and Homoporus febriculosus (Girault) (Pteromalidae) from puparia of Melanagromyza heracleana Zlobin (Diptera: Agromyzidae), and Baryscapus crassicornis (Erdos) (Eulophidae) from larvae, pupae, and adults of Lixus nordmanni Hochhuth (Coleoptera: Curculionidae). The hole(s) or cutting types done by the parasitoids while leaving their hosts were described. Development time from egg to adult (12 days and 19-20 days) and parasitization duration (60 min and 20-30 min) were also determined for P. carlinarum and B. crassicornis, respectively, and average parasitization rates in nature and the mating behaviors of these 2 parasitoids were defined. To our knowledge, the insects are new hosts for all parasitoids and the first parasitoid records for the flies. Chloropidae is a new record host family for D. brunnea after Phoridae. In addition, D. brunnea and H. febriculosus were recorded from Turkey for the first time. [ABSTRACT FROM AUTHOR]

Abstract: The below- and aboveground communities of fungal entomopathogens (Ascomycota: Hypocreales) were investigated in an experimental conventional and organic vegetable cropping system over two seasons in Denmark. The experimental design allowed for evaluating differences between farming practices in the occurrence of soil-borne fungal entomopathogens and as natural infections aboveground in arthropod hosts. Belowground, Metarhizium anisopliae dominated the agricultural field with Beauveria bassiana, Metarhizium flavoviride, and Isaria fumosorosea being present at lower frequencies. Abundances of M. anisopliae were not different between conventional and organic soils. Aboveground, B. bassiana was the most common fungal entomopathogen in arthropod host cadavers. Infections of M. flavoviride, Isaria farinosa, and Gibellula spp. were also recorded. Most mycosed cadavers were recovered in August and September from conventionally farmed plots. Cadaver sizes ranged from 1.9 to 23.6mm with means of 3.7–4.1mm. Among host functional groups, predators dominated (47–63%) over herbivores, parasitoids, and nectar-feeders. No occurrence of M. anisopliae was recorded among >200 mycosed cadavers aboveground. The results therefore suggest that M. anisopliae is not involved in direct below- and aboveground interactions in the investigated agroecosystem. Conservation biological control strategies targeting M. anisopliae should thus be solely for controlling soil-dwelling pests in temperate regions as this fungus is unlikely naturally to infect aboveground hosts in the agroecosytem. [Copyright &y& Elsevier]

Abstract: The safe practice of biological control relies, in part, on an accurate evaluation of a potential agent’s host-specificity via testing through a “filter of safety”. The results of laboratory tests may differ from those obtained in open field host-specificity tests, where agents are able to use their full range of host-selection behaviors. It was hypothesized that Rhinoncomimus latipes (Coleoptera: Curculionidae), the biological control agent released against mile-a-minute weed, Persicaria perfoliata (Polygonaceae), would not feed or oviposit on nontarget plants in a two-phase, open field setting. Ten weevils were placed at the base of each of 13 test plant species in a randomized complete block design with six replicates. Weevils placed at the base of mile-a-minute weed were marked with yellow fluorescent dust, and yellow weevils were subsequently found only on mile-a-minute. Weevils placed at the base of nontarget plants (marked with red fluorescent dust) rapidly colonized mile-a-minute weed. Three hours after release, the number of R. latipes found on mile-a-minute weed was significantly higher than predicted by a random distribution of weevils on all test plants. The likelihood of finding more weevils on mile-a-minute compared to nontarget plant species was 31.0% at 3h and increased to 96.5% at 44h after release. Whereas prerelease studies showed feeding at low levels on 9 of the 13 plant species tested here, under open field conditions R. latipes did not feed on any nontarget plant species and dispersed from these plants. In an open field setting, where the weevil was able to use its full range of host-selection behaviors, there was no observed risk of nontarget effects for any species tested. [ABSTRACT FROM AUTHOR]

The sleeping sickness parasite, Trypanosoma brucei, must differentiate in response to the changing environments that it encounters during its complex life cycle. One developmental form, the bloodstream stumpy stage, plays an important role in infection dynamics and transmission of the parasite. Recent advances have shed light on the molecular mechanisms by which these stumpy forms differentiate as they are transmitted from the mammalian host to the insect vector of sleeping sickness, tsetse flies. These molecular advances now provide improved experimental tools for the study of stumpy formation and function within the mammalian bloodstream. They also offer new routes to therapy via high-throughput screens for agents that accelerate parasite development. Here, we shall discuss the recent advances that have been made and the prospects for future research now available. [ABSTRACT FROM AUTHOR]

1. Individuals of free-living organisms are commonly infected by multiple parasite species. Under such circumstances, positive or negative associations between the species are possible because of direct or indirect interactions, details in parasite transmission ecology and host-mediated factors. One possible mechanism underlying these processes is host immunity, but its role in shaping these associations has rarely been tackled experimentally. 2. In this study, we tested the effect of host immunization on associations between trematode parasites infecting eyes of fish. We first analysed the associations between three species ( Diplostomum spathaceum, Diplostomum gasterostei and Tylodelphys clavata) in wild hosts, roach ( Rutilus rutilus) and perch ( Perca fluviatilis). Second, using rainbow trout ( Oncorhynchus mykiss) as a model fish species, we experimentally investigated how sequential immunization of the host (i.e. one parasite species infects and immunizes the host first) could affect the associations between two of the species. 3. The results indicated that most of the associations were positive in wild hosts, which supports between-individual variation in host susceptibility, rather than competitive exclusion between the parasite species. However, positive associations were more common in roach than in perch, possibly reflecting differences in ecological conditions of exposure between the host species. The experimental data showed that positive associations between two of the species were eroded by host immunization against one of the parasite species. 4. We conclude that sequential immunization of hosts has a marked effect on interspecific parasite associations and basically can determine if positive associations are detected or not. This implies that correlative results suggesting non-interactive community structure in general may be obscured by the sequence of previous parasite exposure and corresponding dynamics of host immunization. [ABSTRACT FROM AUTHOR]

Many species of disease-vector mosquitoes display vertebrate host specificity. Despite considerable progress in recent years in understanding the proximate and ultimate factors related to non-random host selection at the interspecific level, the basis of this selection remains only partially understood. Anopheles gambiae sensu stricto, the main malaria vector in Africa, is considered a highly anthropophilic mosquito, and host odours have been shown to play a major role in the host-seeking process of this species. Studies on host preference of An. gambiae have been either conducted in controlled conditions using laboratory reared mosquitoes and worn stockings as host-related stimuli, or have been done in the field with methods that do not account for internal (e.g. age of sampled mosquitoes) and/or environmental effects. We explored differential behavioural responses to host odours between two populations of the same sibling species, An. gambiae in semi-field conditions in Burkina Faso. The behavioural responses (i.e. degree of activation and strength of anemotaxis) were investigated using a Y-olfactometer designed to accommodate whole hosts as a source of odour stimuli. Two strains of An. gambiae (3 to 4-day-old female) from laboratory Kisumu strain, and from field-collected individuals were confronted to combinations of stimuli comprising calf odour, human odour and outdoor air. In dual-choice tests, field mosquitoes chose human odour over calf odour, outdoor air over calf odour and responded equally to human and outdoor air, while laboratory mosquitoes responded equally to human and calf odour, human odour over outdoor air and calf odour over outdoor air. Overall, no effect of CO2 exhaled by humans and calves neither on the proportion of activated mosquitoes nor on the relative attractiveness to odour stimuli was found. We report for the first time an intraspecific variation in host-odour responses. This study clearly suggests that there may be genetic polymorphism underlying host preference and emphasizes that the highly anthropophilic label given to An. gambiae s.s. must be carefully interpreted and refer to populations rather than the whole sibling species. [ABSTRACT FROM AUTHOR]

Abstract: Polyembryony is a unique mode of development in which multiple genetically identical embryos develop from a single egg. In some polyembryonic species a proportion of the embryos develop into soldier larvae, which attack competitors in the host. We studied the development of the polyembryonic wasp Copidosoma koehleri in its host Phthorimaea opercullela. We dissected hosts parasitized by either virgin or mated female wasps at 2day intervals from hatching to the final instars. We documented host mass and head width, the number and size of developing wasps and the presence of a soldier larva. Additionally, we kept a sample of parasitized hosts until emergence of wasps and measured the head width of emerging adults. We characterized wasp development in relation to host development. One half of the broods produced by mated wasps contained one soldier larva throughout development. This suggests that in C. koehleri each female brood produces a single soldier larva, and that the soldier probably survives and grows gradually during host development. Additionally, we found that female broods were larger than male broods during development and also upon emergence. Accordingly, body size was larger for males during development as well as upon emergence. These findings may extend the existing knowledge on polyembryonic development in general, and serve as a baseline for further experiments. [Copyright &y& Elsevier]

A polymerase chain reaction (PCR)-based assay was used for the specific detection of Habronema microstoma and Habronema muscae (Nematoda, Spirurida) in order to identify the intermediate hosts of both nematode species under field conditions. A total of 1087 netted and 165 laboratory-bred flies were tested. Flies were identified as Musca domestica Linnaeus 1758, Musca autumnalis De Geer 1776, Haematobia irritans (Linnaeus 1758), Haematobia titillans (De Geer 1907) and Stomoxys calcitrans (Linnaeus 1758) (Muscidae). Genomic DNA was extracted from pools of fly heads, thoraces and abdomens, and 703 samples were subjected to a duplex two-step semi-nested PCR assay to specifically detect diagnostic regions within the ribosomal ITS2 sequence of both H. microstoma and H. muscae. Stomoxys calcitrans specimens were positive for H. microstoma DNA and M. domestica specimens were positive for H. muscae DNA. In particular, PCR-positive samples derived from both farm-netted and laboratory-bred flies. The present study represents the first evidence of the vectorial competence of different fly species as intermediate hosts of Habronema stomachworms under field conditions. We discuss the roles of S. calcitrans and M. domestica in transmitting H. microstoma and H. muscae. [ABSTRACT FROM AUTHOR]

Female brood parasites are recognized as threats to reproductive success by many host species. Male brood parasites may accompany females while they search for nests to parasitize and males depredate nests throughout the nesting cycle. Hence, selection may also favour recognition of males. We examined whether two common host species perceive male brown-headed cowbirds ( Molothrus ater) as brood parasites, as nest predators, or neither. We quantified visits of male cowbirds to nests of yellow warblers ( Dendroica petechia) and red-winged blackbirds ( Ageliaus phoeniceus) to assess the frequency with which these host species interact with male cowbirds. Males were observed near nests during hosts’ laying and incubating stages, although less frequently than female cowbirds. No visits by cowbirds occurred while parents cared for nestlings. We then presented models of male and female cowbirds plus a non-threatening control to yellow warblers and red-winged blackbirds during laying and nestling periods. If hosts perceive males and females similarly, they should respond more intensely to the cowbird models during the laying period, when nests are most likely to be parasitized. Both species responded similarly to male and female cowbird models during laying, which suggests that hosts view cowbirds of both sexes as threats. The responses of yellow warblers with nestlings to male cowbirds were strongly influenced by the order of model presentation. Warblers first presented with the male cowbird gave much reduced anti-parasite responses than those that first interacted with the female then the male cowbird. These results suggest that yellow warblers recognized male vs. female cowbirds, but that discrimination was not expressed during laying. By contrast, red-winged blackbirds did not discriminate between male and female cowbirds at either nesting stage. [ABSTRACT FROM AUTHOR]

Background: Studies were conducted between April 2004 and February 2006 to determine the blood-feeding pattern of Anopheles mosquitoes in Mwea Kenya. Methods: Samples were collected indoors by pyrethrum spay catch and outdoors by Centers for Disease Control light traps and processed for blood meal analysis by an Enzyme-linked Immunosorbent Assay. Results: A total of 3,333 blood-fed Anopheles mosquitoes representing four Anopheles species were collected and 2,796 of the samples were assayed, with Anopheles arabiensis comprising 76.2% (n = 2,542) followed in decreasing order by Anopheles coustani 8.9% (n = 297), Anopheles pharoensis 8.2% (n = 272) and Anopheles funestus 6.7% (n = 222). All mosquito species had a high preference for bovine (range 56.3- 71.4%) over human (range 1.1-23.9%) or goat (0.1-2.2%) blood meals. Some individuals from all the four species were found to contain mixed blood meals. The bovine blood index (BBI) for An. arabiensis was significantly higher for populations collected indoors (71.8%), than populations collected outdoors (41.3%), but the human blood index (HBI) did not differ significantly between the two populations. In contrast, BBI for indoor collected An. funestus (51.4%) was significantly lower than for outdoor collected populations (78.0%) and the HBI was significantly higher indoors (28.7%) than outdoors (2.4%). Anthropophily of An. funestus was lowest within the rice scheme, moderate in unplanned rice agro-ecosystem, and highest within the non-irrigated agro-ecosystem. Anthropophily of An. arabiensis was significantly higher in the nonirrigated agro-ecosystem than in the other agro-ecosystems. Conclusion: These findings suggest that rice cultivation has an effect on host choice by Anopheles mosquitoes. The study further indicate that zooprophylaxis may be a potential strategy for malaria control, but there is need to assess how domestic animals may influence arboviruses epidemiology before adapting the strategy. [ABSTRACT FROM AUTHOR]

An important subject of parasite biology is the influence of host on biological parameters. The work was carried out with two groups of engorged Anocentor nitens ticks, one of them fed on bovines ( 93 ticks) and the other on equines (99 ticks). The ticks were weighed in an analytical balance. Each group was divided in eight subgroups (10 to 12 ticks per subgroup) and incubated at two temperatures, 26 °C and 32°C and four relative humidities, 100, 80, 75.5 and 70 %. In each subgroup, laying efficiency (total egg mass weight/female weight, in percentage) and pre-eclosion period (from the beginning of incubation to the eclosion of the first larvae) were studied. The layer efficiency of the two main groups was compared by a three factor variance analysis, being the factors temperature, relative humidity and host species. A similar test was carried out to compare pre-eclosion. Duncan test was employed for multiple mean comparisons in both variables. The host species had an influence on the weight of engorgement and on the laying efficiency. Pre-eclosion was not afected by the host. [ABSTRACT FROM AUTHOR]

Mechanisms of recognition are essential to the evolution of mutualistic and parasitic interactions between species. One such example is the larval mimicry that Maculinea butterfly caterpillars use to parasitize Myrmica ant colonies. We found that the greater the match between the surface chemistry of Maculinea alcon and two of its host Myrmica species, the more easily ant colonies were exploited. The geographic patterns of surface chemistry indicate an ongoing coevolutionary arms race between the butterflies and Myrmica rubra, which has significant genetic differentiation between populations, but not between the butterflies and a second, sympatric host, Myrmica ruginodis, which has panmictic populations. Alternative hosts may therefore provide an evolutionary refuge for a parasite during periods of counteradaptation by their preferred hosts. [ABSTRACT FROM AUTHOR]

[Objective] To conduct morphological and molecular identification on a strain of entomogenous fungus collected from Baji Village, Bayi Town, Nyingchi County, Tibet in July 2015. [Methods] The fungal ITS sequence identification and analysis were conducted. [Results] The degree of similarity in ITS sequence between the entomogenous fungus and Ophiocordyceps sinensis was 83%. The host insect was Thitarodes pui, with COI gene similarity of 99%. [Conclusions] Based on morphological analysis, it was found that this entomogenous fungus might fall within the group of Ophiocordyceps sinensis. [ABSTRACT FROM AUTHOR]