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Minute insects such as parasitic micro-wasps have high basic and applied importance for their widespread use as biocontrol agents. Their dispersal is a phenotype of particular interest. Classically, it is evaluated using field releases, but those are time consuming, costly, and their results highly variable, preventing high-throughput and repeatability. Alternatively, dispersal can be studied using small-scale assays, but those neglect important higher-scale processes. Consequently, proper evaluation of dispersal is often complicated or lacking in academic studies and biocontrol breeding programs. Here we introduce a new method, the double-spiral maze, that allows the study of spatial propagation of groups of micro-wasps at relevant scales (several hours and meters), retaining high throughput and experimental power. The method records the location of every individual at every time, enabling accurate estimates of diffusion coefficients or other dispersal metrics. We describe this affordable, scalable, and easy-to-implement method, and illustrate its application with a species of agricultural interest. [ABSTRACT FROM AUTHOR]

Cabbage butterfly (Pieris brassicae) is major pest of cabbage. More than 50% yield losses have been attributed due to this pest annually. Seven insect parasitic nematodes i.e. Steinerma carpocapsae, S. feltiae, S. Pakitananese, S. asiaticum, S. glaseri, Heterorhabditis bacteriophora and H. indica were evaluated on 4th larval instar of P. brassicae at the different concentrations. Two best performing EPNs (S. glaseri and H. bacteriophora) were selected and evaluated against 2nd, 3rd and 4th larval instars of Pieris brassicae at 1500 infective juveniles/ml. H. bacteriophora spp. and S. glaseri spp. were sprayed at 1500 IJs/ml on the cabbage leaves alone or in combination (S. glaseri + H. bacteriophora) and 2nd, 3rd and 4th larval instars were fed on them. Among seven EPNs, hundred percent mortality of P. brassicae was recorded in the case of H. bacteriophora and S. glaseri at1500 IJs/ml concentration after 48 h. Both EPNs spp. were found highly effective against all larval instars of P. brassicae. After 48 h of exposure of both EPNs spp. on all larval instar, 100% mortality was recorded. The combined application of H. bacteriophora + S. glaseri on cabbage leaves resulted into 100% mortality of all larval instars of P. brassicae. From present study, it may be concluded that H. bacteriophora and S. glaseri at 1500 IJs/ml concentration found very effective against P. brassicae in laboratory conditions and may be used in the field conditions. [ABSTRACT FROM AUTHOR]

Various organisms, especially arthropods, are able to live as parasites in ant nests and to prey upon ant broods without eliciting any aggressive behaviour in the hosts. Understanding how these intruders are able to break the ants' communication codes in their favour represents a challenging and intriguing evolutionary question. We studied the chemical strategies of three European hoverfly species, Microdon mutabilis (parasitic on Formica cunicularia), M. analis (parasitic on Lasius emarginatus) and M. devius (parasitic on L. distinguendus). The peculiar slug-like larvae of these three species live inside ant nests feeding upon their broods. Gas chromatography-mass spectrometry analyses show that: 1) these parasites mimic the host brood rather than the ant workers, although each differs distinctly in the extent of chemical mimicry; 2) isolation experiments indicate that after 14 days the responsible cuticular hydrocarbons (CHCs) are not passively acquired but synthesized by the fly larvae. Additionally, Microdon larvae show an array of protective structural features, such as a thick and multi-layered cuticle, retractable head, dome-shaped tergum and a flat and strongly adhesive "foot" (sternum). This combination of protective chemical and structural features represents a successful key innovation by Microdon species, and one that may facilitate host switching. The results of a preliminary adoption analysis confirm that Microdon larvae of at least some species can readily be accepted by different species of ants. [ABSTRACT FROM AUTHOR]

Purpose: The Manx shearwater flea Ceratophyllus (Emmareus) fionnus Usher, 1968 is a host-specific parasitic insect apparently restricted to the Isle of Rùm, off the west coast of Scotland. Although C. (E.) fionnus is one of only a small number of insect species endemic to the British Isles, its conservation status has never been evaluated. To enable effective management, the conservation status of the species was assessed. Methods: The conservation status of C. (E.) fionnus was evaluated using host and distribution records in conjunction with two assessment rubrics; the IUCN Red List Categories and Criteria: Version 3.1, and a flea-specific assessment rubric developed previously. Results: Ceratophyllus (Emmareus) fionnus was found to be threatened with extinction due to its hyperendemicity on the Isle of Rùm and was classified as vulnerable. Conclusion: Based on the findings of the assessment, immediate conservation action to protect C. (E.) fionnus is encouraged and a recovery plan is outlined. This includes surveys and studies of the bionomics of the species in conjunction with in-situ management of the known population. The creation of insurance populations through conservation translocations is also encouraged. [ABSTRACT FROM AUTHOR]

Malaria is an infectious disease caused by Plasmodium parasites and is transmitted among humans by female Anopheles mosquitoes. Climate factors have significant impact on both mosquito life cycle and parasite development. To consider the temperature sensitivity of the extrinsic incubation period (EIP) of malaria parasites, we formulate a delay differential equations model with a periodic time delay. We derive the basic reproduction ratio $$R_0$$ and establish a threshold type result on the global dynamics in terms of $$R_0$$ , that is, the unique disease-free periodic solution is globally asymptotically stable if $$R_0<1$$ ; and the model system admits a unique positive periodic solution which is globally asymptotically stable if $$R_0>1$$ . Numerically, we parameterize the model with data from Maputo Province, Mozambique, and simulate the long-term behavior of solutions. The simulation result is consistent with the obtained analytic result. In addition, we find that using the time-averaged EIP may underestimate the basic reproduction ratio. [ABSTRACT FROM AUTHOR]

In this study, a total of 4146 culicids collected in an Atlantic Forest area in Paraná state, southern Brazil were examined for the presence of mites. Forty larval Parasitengone mites ( Arrenurus spp., Arrenuridae; Durenia spp., Trombellidae; Microtrombidium spp., Microtrombidiidae) parasitized 25 specimens of mosquitoes, with the intensity varying from one to nine mites attached. Most mites were found on Aedes serratus/nubilus, Culex vomerifer, Cx. pedroi and Cx. sacchettae. The overall percentage of parasitized mosquitoes was 0.6 %. The highest intensity of mites encountered was in an individual of Cx. pedroi with nine attached mites. Regarding the attachment site, most mite specimens were attached to the abdomen (n = 25), whereas 15 were located on the thorax. Specimens of Arrenurus spp. were only found on the abdomen of mosquitoes, and the same was observed for Microtrombidium spp., while Durenia spp. attached to both the thorax (n = 15) and abdomen (n = 4). This is the first record for the genus Durenia in Brazil. Additionally, some species of mosquitoes were, for the first time, reported as being parasitized by mites. [ABSTRACT FROM AUTHOR]

During the years 2010 to 2013, parasitoid wasps (Hymenoptera: Chalcidoidea) were collected in Israel from five Kermes species (Hemiptera: Coccoidea: Kermesidae), namely, Kermes echinatus Balachowsky , K. greeni Bodenheimer , K. hermonensis Spodek and Ben-Dov, K. nahalali Bodenheimer and K. spatulatus Balachowsky . These collections resulted in thirteen parasitoid species including four species that are new to science: Aprostocetus bendovi Japoshvili sp.n., A. ghanimi Japoshvili sp.n., A. mendeli Japoshvili sp.n. and A. protasovi Japoshvili sp.n., seven new records for Israel, and nine species with sixteen new scale insect hosts. [ABSTRACT FROM AUTHOR]

The occurrence of Hypoderma diana (Diptera: Hypodermatidae) in a herd of 15 horses was observed during a 4-year period (2010-2013) in northwest Bohemia. During this period, infestation by the warble fly H. diana increased from 12.5 % in 2010 to 53.3 % in 2013. Nodules were observed on the neck, back, stomach, legs, and head. The incidence of H. diana was probably influenced by the presence of a specific host mouflon ( Ovis orientalis musimon). [ABSTRACT FROM AUTHOR]

Psyttalia concolor (Szépligeti) (Hymenoptera: Braconidae) is a koinobiont larval-pupal endoparasitoid of many Tephritidae of economic importance. Little has been reported on the ability of females to discriminate between healthy and parasitized hosts, as well as parasitized versus superparasitized larvae. Two-choice bioassays were conducted to evaluate the preferences of P. concolor naïve females for healthy or single-parasitized/superparasitized C. capitata larvae, as well as the host discrimination ability among medfly larvae which had been superparasitized by the same wasp or by a conspecific one. Psyttalia concolor preferred to oviposit in a unparasitized C. capitata larva than in a self-parasitized one. Females also showed an innate ability to discriminate between larvae parasitized twice or only once, preferring the latter. This ability helps the female to optimise its oviposition decisions by deliberately avoiding superparasitized hosts, since it is known that they give a lower return in offspring number and quality than do singly parasitized hosts. Our findings contribute to a better knowledge of the P. concolor host location behaviour and also to improve its mass-rearing technique through a rational management of the host/parasitoid ratio and the host exposure time. Indeed, the proper setting of these parameters allows to reduce the fraction of single-parasitized and heavily superparasitized larvae and to enhance P. concolor rearing in terms of parasitoid offspring. [ABSTRACT FROM AUTHOR]

We investigated the effects of sequential adult learning experiences (postemergence + ovipositional) with two host foodplants (tomato and/or tobacco) on searching responses, clutch size, and sex ratio allocations of Cotesia congregata, a gregarious endoparasitoid of Manduca sexta. Sequential experiences with one host foodplant resulted in a stronger searching response to the plant experienced and a higher proportionate allocation of females to hosts offered with this plant. Sequential experiences with both plants resulted in similar searching responses to the two plants and similar proportionate allocations of females, irrespective of the order in which plants were experienced. Ovipositional experience resulted in a stronger searching response to the plant experienced but effects on sex ratio allocations were not definitive. Clutch size was not modified by experience. Results demonstrate that parasitic wasps can learn multiple host-associated plant cues and suggest that sequential learning experiences serve to define the effective host foodplant range. [ABSTRACT FROM AUTHOR]

Olfactory learning is generally involved in the host-finding process in parasitic wasps. But the reliability of odour cues for predicting future host-finding success depends on the rate at which host-substrate associations are subject to variation within and between parasitoid generations. Since learning comes at physiological costs, we can expect animals to learn in a way that optimizes costs and benefits. The parasitic wasp Venturia canescens occurs in two reproductive modes that forage in different environments. We tested populations from both habitat types for learning rate, memory duration and speed of decision making and found considerable differences. Thelytokous wasps live in habitats with relatively stable host-substrate associations and might encounter hosts at a high rate. They showed a preference for a new odour after only a single experience. However, the response faded within 24 h, even with spaced learning experiences. Arrhenotokous wasps live in habitats where hosts are scarce and are likely to be found on a variety of substrates. Like the thelytokous ones, arrhenotokous wasps learned a new odour after a single experience, but seemingly took long for information processing: one and four hours after an experience, a speed-accuracy trade-off became visible, while 24 h after the experience, wasps decided quickly and in accordance with what they had learned. In addition, these wasps are likely to have developed an aversion response towards Geraniol in the CleanAir experiment. We conclude that the respective cognitive pattern can be attributed to the ecological circumstances of the wasp's natural habitat. [ABSTRACT FROM AUTHOR]

Portschinskia magnifica Pleske, 1926, is an endangered subcutaneous parasitic fly of voles that mimics bumblebees in appearance. Although the importance of antennae in Diptera has been repeatedly stressed, there is still a lack of morphology information of this group, let alone this species. Antennae of adult P. magnifica were studied with a stereoscopic microscope and scanning electron microscope. Six subtypes of antennal sensilla were observed on the funiculus and arista (one subtype of trichoid sensilla, one subtype of basiconic sensilla, and four subtypes of coeloconic sensilla). Sensilla on the antennal funiculus from one sample of both male and female flies were also mapped. Female P. magnifica bear a larger number of sensilla than males, and more sensilla were discovered on the posterior surface than on the anterior surface. However, what make this species special are the distinct structures and new morphological characteristics discovered in the antenna. The antennal funiculus of P. magnifica is completely enveloped by an antennal pedicel. A large number of branched or unbranched trichoid and basiconic sensilla are identified on the antennal funiculus. These two make the most numerous types of sensilla distributed all over the funicular surface. P. magnifica has the most coeloconic sensilla subtypes in previously studied oestrid flies. A total of four subtypes of coeloconic sensilla are found, with subtype I and subtype II on the proximal and middle part of the antennal funiculus and subtype III and subtype IV on the antennal arista. Two large bristles that resemble mechanoreceptors on the proximal two antennal segments located close to the arista are a unique feature. This has never been described in the oestrid funiculus. Interestingly, these bristles can appear as multi-tipped short structures in some individuals. P. magnifica lacks sensory pits that are usually abundant in other oestrid flies. The size, number, and distribution of sensilla on the male and female antennal funiculus are provided here, armed with a discussion of their presumable sensilla functions and evolutionary trends. [ABSTRACT FROM AUTHOR]

The efficacy of Cassia alata against cestode Hymenolepis diminuta was evaluated in our study. Worms were maintained between rat model and beetle. Air-dried leaves of C. alata were subjected to ethanol extraction. Different concentrations (10-80 mg/ml) of the extract were prepared in phosphate buffer saline and tested on the parasite in vitro. Parasites treated with C. alata showed a decrease in motility with an increase in concentrations and complete immobilization took lesser time compared to control. The paralyzed parasites were further processed for electron microscopic studies. Ultrastructural micrographs revealed swelling of the tegument and blebbing on the tegumental surface throughout the body accompanied with destruction of microtriches and changes such as shrinkage in the scolex region. Depletion of parenchyma cells and destruction in the connective tissues along with sparsely cytoplasmic cytons were also observed, and these observations are similar with worms treated with a known drug praziquantel. These results may suggest that the plant leaves could be considered for controlling helminth infection and can represent a step forward in the search for alternative anthelmintic drug. [ABSTRACT FROM AUTHOR]

Life history of the parasitoid species, Habrobracon hebetor Say (Hymenoptera: Braconidae) was studied in the laboratory when parasitizing larvae of Cadra cautella (Walker) (Lepidoptera: Pyralidae) infesting stored date fruits. Mean adult longevity was 7.9 and 6.6 days for female and male, respectively. Pre-ovopositional and ovipositional periods lasted < 12h and 7.4 days, respectively. Total number of eggs/ female was 69.3 eggs, with a mean of 9.45 eggs/ day. Mean durations of immature stages reached 14.99 hrs, 2.48 and 5.65 days for egg, larval and pupal stages, respectively. Egg hatchability, pupation and adult emergence recorded more than 95%. The larvae of H. hebetor could externally parasitize all larval instars of C. cautella. However, the parasitoid preferred late larval instars of C. cautella. Parasitism rate was significantly different among the instars. [ABSTRACT FROM AUTHOR]

Nosema ceranae is a relatively new and widespread parasite of the western honeybee Apis mellifera that provokes a new form of nosemosis. In comparison to Nosema apis, which has been infecting the honeybee for much longer, N. ceranae seems to have co-evolved less with this host, causing a more virulent disease. Given that N. apis and N. ceranae are obligate intracellular microsporidian parasites, needing host energy to reproduce, energetic stress may be an important factor contributing to the increased virulence observed. Through feeding experiments on caged bees, we show that both mortality and sugar syrup consumption were higher in N. ceranae-infected bees than in N. apis-infected and control bees. The mortality and sugar syrup consumption are also higher in N. apis-infected bees than in controls, but are less than in N. ceranae-infected bees. With both microsporidia, mortality and sugar syrup consumption increased in function of the increasing spore counts administered for infection. The differences in energetic requirements between both Nosema spp. confirm that their metabolic patterns are not the same, which may depend critically on host-parasite interactions and, ultimately, on host pathology. The repercussions of this increased energetic stress may even explain the changes in host behavior due to starvation, lack of thermoregulatory capacity, or higher rates of trophallaxis, which might enhance transmission and bee death. [ABSTRACT FROM AUTHOR]

The tortoise tick Hyalomma aegyptium has a typical three-host life-cycle. Whereas its larvae and nymphs are less host-specific feeding on a variety of tetrapods, tortoises of the genus Testudo are principal hosts of adults. Ticks retained this trait also in our study under laboratory conditions, while adults were reluctant to feed on mammalian hosts. Combination of feeding larvae and nymphs on guinea pigs and feeding of adults on Testudo marginata tortoises provided the best results. Feeding period of females was on average 25 days (range 17-44), whereas males remain after female engorgement on tortoise host. Female pre-oviposition period was 14 days (3-31), followed by 24 days of oviposition (18-29). Pre-eclosion and eclosion, both together, takes 31 days (21-43). Larvae fed 5 days (3-9), then molted to nymphs after 17 days (12-23). Feeding period of nymphs lasted 7 days (5-10), engorged nymphs molted to adults after 24 days (19-26). Sex ratio of laboratory hatched H. aegyptium was nearly equal (1:1.09). The average weight of engorged female was 0.95 (0.72-1.12) g. The average number of laid eggs was 6,900 (6,524-7,532) per female, it was significantly correlated with weight of engorged female. Only 2.8% of engorged larvae and 1.8% of engorged nymphs remained un-molted and died. Despite the use of natural host species, feeding success of females reached only 45%. The whole life-cycle was completed within 147 days (98-215). [ABSTRACT FROM AUTHOR]

We investigated the effect of prolonged exposure to low temperature on engorged females of Rhipicephalus sanguineus. Five groups of two females (F1-F5) were maintained at 8 ± 2°C, 70 ± 10% RH, and 24 h scotophase, for 15, 30, 45, 60 and 75 days. One group was maintained in the incubator (26 ± 1°C, 70 ± 10% RH, and 24 h scotophase) as control. The results show that egg hatch rate, longevity and reproductive fitness of engorged females of R. sanguineus are negatively correlated with the duration of exposure to low temperature, whereas preoviposition period was positively correlated with exposure to the cold. This shows that the engorged female ticks are sensitive to prolonged exposure to low temperature, and it may explain why females of this tick species are not reproductively active during winter. Our results confirm that temperature is a major limiting factor for the establishment of stable R. sanguineus populations in cold temperate regions of Europe. [ABSTRACT FROM AUTHOR]

The systematics of the Ostertagiinae is unsettled with no agreement on how many genera and species are present in cattle and sheep. Ten species of Ostertagiinae are commonly parasitic in cattle and sheep. In the global fauna, six of 13 ostertagiine genera are endemic to Iran. The life cycle of Ostertaginae is direct and ingested third-stage larvae after exsheatment in the rumen, penetrate the gastric glands in the abomasal mucosa where two parasitic moults occur before the L5 emerges from the gland. In the present work, Marshallagia marshalli and Ostertagia occidentalis, collected from the abomasums of sheep from Mashhad, Iran, is described. The association of light and scanning electron microscopy (SEM) allowed a detailed analysis of the morphology and ultrastructure of these nematodes. The male body length of M. marshalli and O. occidentalis were 9.3-10.20 and 9.60-10.50 mm, respectively. The female body length of M. marshalli and O. occidentalis were 10.10-15.30 and 10.4-15.70 mm, respectively. One of cervical papillae is seen 333 and 250 μm from the anterior end of male and female body surface in O. occidentalis and 287.5 and 200 μm from the anterior end of male and female body surface in M. marshalli, respectively. The size of cervical papillae is 13.3 μm in male and 10 μm in female in O. occidentalis and 9.33 μm in male and 8.57 μm in female in M. marshalli. Some other taxonomic features of M. marshalli and O. occidentalis, such as details of cephalic region, the system of longitudinal and surface cuticular ridges (synlophe), the orientation of rays of the copulatory bursa, localization of vulva, morphology of vulvar flap, and posterior end of females are also documented by SEM. [ABSTRACT FROM AUTHOR]

The main function of cuticular lipids in insects is the restriction of water transpiration through the surface. Lipids are involved in various types of chemical communication between species and reduce the penetration of insecticides, chemicals, and toxins and they also provide protection from attack by microorganisms, parasitic insects, and predators. Hydrocarbons, which include straight-chain saturated, unsaturated, and methyl-branched hydrocarbons, predominate in the cuticular lipids of most insect species; fatty acids, alcohols, esters, ketones, aldehydes, as well as trace amounts of epoxides, ethers, oxoaldehydes, diols, and triacylglycerols have also been identified. Analyses of cuticular lipids are chemically relatively straightforward, and methods for their extraction should be simple. Classically, extraction has relied mainly on application of apolar solvents to the entire insect body. Recently, several alternative methods have been employed to overcome some of the shortcomings of solvent extraction. These include the use of solid-phase microextraction (SPME) fibers to extract hydrocarbons from the headspace of heated samples, SPME to sample live individuals, and a less expensive method (utilized for social wasps), which consists of the collection of cuticular lipids by means of small pieces of cotton rubbed on the body of the insect. Both classical and recently developed extraction methods are reviewed in this work. The separation and analysis of the insect cuticular lipids were performed by column chromatography, thin-layer chromatography (TLC), high performance liquid chromatography with a laser light scattering detector (HPLC-LLSD), gas chromatography (GC), and GC-mass spectrometry (MS). The strategy of lipid analysis with the use of chromatographic techniques was as follows: extraction of analytes from biological material, lipid class separation by TLC, column chromatography, HPLC-LLSD, derivatization, and final determination by GC, GC-MS, matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) MS, and liquid chromatography-mass spectrometry (LC-MS). [ABSTRACT FROM AUTHOR]

A common strategy of pathogenic bacteria is to form close associations with parasitic insects that feed on animals and to use these insects as vectors for their own transmission. Pathogens interact closely with other coexisting bacteria within the insect, and interactions between co-occurring bacteria may influence the vector competency of the parasite. Interactions between particular lineages can be explored through measures of α-diversity. Furthermore, general patterns of bacterial community assembly can be explored through measures of β-diversity. Here, we use pyrosequencing (n=115 924 16S rRNA gene sequences) to describe the bacterial communities of 230 prairie dog fleas sampled across space and time. We use these communinty characterizations to assess interactions between dominant community members and to explore general patterns of bacterial community assembly in fleas. An analysis of co-occurrence patterns suggests non-neutral negative interactions between dominant community members (P<0.001). Furthermore, bacterial communities of fleas shift dramatically across years (phylotype-based: R=0.829, P<0.001; phylogenetic-based: R=0.612–0.753, P<0.001), but they also significantly differ across space (phylotype-based: R=0.418, P<0.001; phylogenetic-based: R=0.290–0.328, P<0.001) and between flea species (phylotype-based: R=0.160, P=0.011; phylogenetic-based: not significant). Collectively, our results show that flea-associated bacterial communities are not random assemblages; rather, an individual flea's bacterial community is governed by interactions between bacterial lineages and by the flea's place in space and time. [ABSTRACT FROM AUTHOR]

A survey of common ichneumonoid (braconid and ichneumonid) parasitoid wasp species and their relative abundances in Suez Canal Region; Ismailia and North Sinai Governorates, using Malaise trap, was carried out for two successive years 2007 and 2008. Biweekly catches were collected, classified and identified. The survey revealed the presence of a total number of 52 ichneumonoid species; 20 braconid species (of which 4 haven't been identified yet) and 32 ichneumonid species (of which 7 haven't been identified yet). The 16 identified braconid species belong to 14 genera and 7 subfamilies, while the 25 ichneumonid species belong to 19 genera and 10 subfamilies. Collected specimens were identified by the authors and were sent to the specialists abroad for confirmation. A checklist of the recorded identified species and their abundances was provided. [ABSTRACT FROM AUTHOR]

The hair follicle mites of the genus Demodex (Demodecidae) were first discovered in humans in 1841. Since then, members of this host-specific genus have been found in 11 of the 18 orders of eutherian mammals with most host species harboring two or more species of Demodex. Humans are host to D. folliculorum and D. brevis. The biology, natural history, and anatomy of these mites as related to their life in the human pilosebaceous complex is reviewed. This information may provide insight into the application of Demodex as a tool for the forensic acarologist/entomologist. [ABSTRACT FROM AUTHOR]

Abstract   Blastocystis sp. is the most common eukaryotic parasite in the intestinal tract of humans. Due to its strong impact in public health, in this study, we determined the frequency of different Blastocystis subtypes in patients in France. We hypothesized on the mode of transmission and tested a possible relationship between the subtype and symptomatic status. We obtained a total of 40 stool samples identified as positive for Blastocystis by microscopic examination of smears. Participants consisted of 25 symptomatic and 15 asymptomatic patients, for whom clinical and parasitological data were collected. For nested-polymerase chain reaction and genotyping, DNA was extracted directly from fecal samples or from fecal cultures. Morphological forms observed in fecal cultures were uncorrelated with symptomatic status. Genotyping using partial small subunit rRNA gene analysis identified a total of 43 Blastocystis isolates corresponding to 37 single infections and three mixed infections by two different subtypes. These 43 isolates belonged to five subtypes (1, 2, 3, 4, and 7) with predominance of subtype 3 (53.5%). Patient symptomatic status was uncorrelated with Blastocystis subtype. [ABSTRACT FROM AUTHOR]

Effects of Neem Azal T/S on the predaceous insects; Chrysoperla carnea Steph. and Coccinella undecimpunctata L. were evaluated. Experiments were carried out using three concentrations; 50, 100, and 200ppm .When larvae of predators fed on sprayed aphid nymphes, larval mortalities, 72 h post treatment, at low (50ppm) and high (200ppm) concentrations were 26.1 and 43.4% for Ch. carnea and 28.6 and 52.4 %for C. undecimpunctata, respectively. The corresponding percentages of survivors failed to pupate, due to the latent effect of Neem Azal T/S, were 5.88 & 23.07% and 6.67 & 20.0%, respectively. In case of topical application of larvae, larval mortalities, 72 h post treatment, at low (50ppm) and high (200 ppm) concentrations were 31.8 and 54.5% for Ch .carnea and 42.9 and 52.4% for C. undecimpunctata, respectively. The corresponding percentages of survivors faild to pupate, due to the latent effect of Neem AzalT/S,were 13.33 & 30% and 8.33 & 20%, respectively. However, no or negligible effects were found in two treatments on adults emergence percentages from normally formed pupae in both. species. Protein analysis of C. undecimpunctata adults was carried out using the electrophoresis technique. Data showed that the molecular weight, ranged between 23-119 kD, 23-118 kD , 20-118 kD and 23-118 kD, at the concentrations 50 ,100, 200 ppm and control, respectively. In conclusion, NeemAzal T/S should be used safely at relatively low rates of application. [ABSTRACT FROM AUTHOR]

Survey and population density of the aphid species Aphis craccivora (Koch) infesting broad bean plants and its parasitoids were studied at Zagazig district during the two successive seasons 2006-07 and 2007-08. Two primary parasitoids, Diaeretiella rapae (M'Intosh), Ephedrus sp. (Aphidiidae), and a hyperparasitoid, Aphidencyrtus sp. (Encyrtidae) were recorded. Highest rates of parasitism 12.73% were recorded in the 4th week of January 2006-07 and 11.09% in the 2nd week of February 2007-08. Seasonal means of parasitism rates of the primary parasitoids D. rapae and Ephedrus sp. were 8.17 and 6.45% during the two seasons, respectively. Total developmental period of the two parasitoids was investigated at three temperatures (10, 15 and 28 °C). The duration of the two parasitoids was longest at 10 °C. Generally, developmental periods of different stages of the parasitoids shortened as the temperature increased from 10 to 28 °C. Total developmental periods of the two parasitoids ranged between 11.17-27.16 and 12.38-30.48 days for D. rapae and Ephedrus sp., respectively. Sex ratios were 1:1.1 and 1:1.07 (m:f) for D. rapae and Ephedrus sp., respectively. Temperature and relative humidity played an important role in the population changes of A. craccivora, D. rapae and Ephedrus sp. Temperature showed a highly significant effect on the population density of Ephedrus sp. in both seasons. The maximum temperature and the minimum relative humidity had a positive significant effects on the population density of D. rapae at both seasons. [ABSTRACT FROM AUTHOR]

To cope with environmental variability, animals should gather and use information to reduce uncertainty. In insect parasitoids, associative learning has been widely documented in the context of host foraging. However, despite its potential adaptive value, the insect food searching strategy and cues used to search are poorly understood. In this study, we examined the ability of hymenopteran Venturia canescens females to associate food to a visual cue. To broaden the scope of our results, experiments were performed with both arrhenotokous (sexual) and thelytokous (asexual) individuals. The wasps showed innate attraction for yellow and orange stimuli when presented versus blue stimuli. When trained to associate a food reward with one of the attractive colours (orange), they significantly moved from a distance towards the colour previously associated with food. The choice of the innately preferred colour (yellow) was not modified by associative learning. In the context of food foraging, this study is the first to show associative learning using visual stimuli in a parasitoid and active choice of this colour. This ability gives new insights concerning potential food sources for V. canescens in the field, since flowers are sugar sources, which emit colour signals. [ABSTRACT FROM AUTHOR]

Mites in the genus Tropilaelaps are parasites of social honeybees. Two species, Tropilaelaps clareae and T. koenigerum, have been recorded and their primary hosts are presumed to be the giant honeybees of Asia, Apis dorsata and A. laboriosa. The most common species, T. clareae, is also an economically important pest of the introduced Western honeybee (A. mellifera) throughout Asia and is considered an emerging threat to world apiculture. In the studies reported here, genetic (mtDNA CO-I and nuclear ITS1-5.8S-ITS2 gene sequence) and morphological variation and host associations were examined among Tropilaelaps isolates collected from A. dorsata, A. laboriosa and A. mellifera throughout Asia and neighbouring regions. The results clearly indicate that the genus contains at least four species. Tropilaelaps clareae, previously assumed to be ubiquitous in Asia, was found to be two species, and it is here redefined as encompassing haplotypes (mites with distinct mtDNA gene sequences) that parasitise native A. dorsata breviligula and introduced A. mellifera in the Philippines and also native A. d. binghami on Sulawesi Island in Indonesia. Tropilaelaps mercedesae n. sp., which until now has been mistaken for T. clareae, encompasses haplotypes that, together with haplotypes of T. koenigerum, parasitise native A. d. dorsata in mainland Asia and Indonesia (except Sulawesi Island). It also parasitises introduced A. mellifera in these and surrounding regions and, with another new species, T. thaii n. sp., also parasitises A. laboriosa in mountainous Himalayan regions. Methods are described for identifying each species. These studies help to clarify the emerging threat of Tropilaelaps to world apiculture and will necessitate a revision of quarantine protocols for countries that import and export honeybees. [ABSTRACT FROM AUTHOR]

Colony infestation by the parasitic mite, Varroa destructor is one of the most serious problems for beekeeping worldwide. In order to reproduce varroa females, enter worker or drone brood shortly before the cell is sealed. To test the hypothesis that, due to the preference of mites to invade drone brood to reproduce, a high proportion of the mite reproduction should occur in drone cells, a comparative study of mite reproductive rate in worker and drone brood of Africanized honey bees (AHB) was done for 370 mites. After determining the number, developmental stage and sex of the offspring in worker cells, the foundress female mite was immediately transferred into an uninfested drone cell. Mite fertility in single infested worker and drone brood cells was 76.5 and 79.3%, respectively. There was no difference between the groups (X² = 0.78, P = 0.37). However, one of the most significant differences in mite reproduction was the higher percentage of mites producing viable offspring (cells that contain one live adult male and at least one adult female mite) in drone cells (38.1%) compared to worker cells (13.8%) (X² = 55.4, P < 0.01). Furthermore, a high level of immature offspring occurred in worker cells and not in drone cells (X² = 69, P < 0.01). Although no differences were found in the percentage of non-reproducing mites, more than 74% (n = 85) of the mites that did not reproduce in worker brood, produced offspring when they were transferred to drone brood. [ABSTRACT FROM AUTHOR]

Callicarpenal (13, 14, 15, 16-tetranor-3-cleroden-12-al) and intermedeol [(4S,5S,7R,10S)-eudesm-11-en-4-ol], isolated from American beautyberry, Callicarpa americana (Lamiaceae), were evaluated in laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick, Ixodes scapularis, and lone star tick, Amblyomma americanum. A strip of organdy cloth treated with test solution was doubly wrapped (treatment on outer layer) around the middle phalanx of a forefinger and ticks released on the fingertip. Callicarpenal and intermedeol, at 155 nmole/cm² cloth repelled 98 and 96% of I. scapularis nymphs, respectively. Dose response tests with I. scapularis nymphs showed no difference in repellency among callicarpenal, intermedeol and Deet (N,N-diethyl-3-methylbenzamide), however, SS220 ((1S,2′S)-2-methylpiperidinyl-3-cyclohexene-1-carboxamide) was significantly more repellent than the other compounds. Callicarpenal, at 155 nmole/cm² cloth, repelled 100 and 53.3% of I. scapularis nymphs at 3 and 4 h, respectively, after the cloth was treated, whereas intermedeol repelled 72.5% of I. scapularis nymphs 3 h after treatment. In comparison with the results obtained with I. scapularis, callicarpenal, intermedeol, Deet and SS220 were less effective against A. americanum. Only intermedeol and SS220 repelled significantly more A. americanum than ethanol controls at 155 nmole compound/cm² cloth. At 1,240 nmole/cm² cloth, callicarpenal and intermedeol repelled 20 and 40% of A. americanum nymphs. [ABSTRACT FROM AUTHOR]

We investigated the empirical relationship between mean abundance and its variance, known as Taylor’s power law, in fleas parasitic on small mammals. It has been suggested that the exponent of this function, b, represents a true biological character of a species and, dependent on the level of host specificity, varies among species. Other empirical and theoretical studies suggest that exponent b depends on interspecific competition and varies intraspecifically. We tested these hypotheses using data from central and eastern Slovakia. We demonstrate that the slope of Taylor’s relationship (a) is repeatable within a flea species, i.e. the slope represents a true species character; (b) increases with an increase of the degree of flea host specificity; and (c) decreases with an increase in flea community size. We discuss our results with the idea that the host can mediate interactions among and within flea species. [ABSTRACT FROM AUTHOR]

Reports on the adoption of nature processes in developing new materials and processing solutions as of March 2004. Employment of the photosynthetic process of plants in developing a process to manipulate nanoscale platinum particles; Results of a study on the secret of mussels' glue; Creation of a prototype hearing aid with the help of the model structures found in the ears of the Ormia ochracea fly.

Despite the vast diversity of parasitic insects and their importance in natural and agricultural communities, our knowledge of what determines their patterns of association with hosts remains sparse. Unlike most parasites that tend to be specialized, parasitoid flies in the family Tachinidae exhibit a broad spectrum of host-specificity, with many species attacking a wide range of hosts. This variability in host-specificity makes them a useful model for examining the ecological and historical factors that determine host associations. We analyzed data collected from a 5-year rearing program of Lepidoptera in southern Arizona to investigate the factors that influence tachinid-host associations. After controlling for a strong effect of sample size, a significant portion of the remaining variance in host range was explained by differences among phylogenetic groups of tachinids and/or their correlated reproductive strategies. Relatively specialized tachinids tended to be associated with monophagous or narrowly oligophagous hosts and attacked them at relatively high frequencies, a pattern we suggest is related to host location efficiency. Cluster analysis indicated that host abundance, gregariousness, food-plant type, and morphology are all important determinants of tachinid host use. Little concordance was found between how tachinid species cluster according to characteristics of their hosts and their estimated phylogenetic relationships. Together, the results of this study suggest that ecological factors are important determinants of host use in these parasitoids and although phylogenetic history may influence the range of hosts used, its power to explain the ecological or taxonomic character of hosts used appears limited. [ABSTRACT FROM AUTHOR]

Discusses mites in the genus Varroa that are the primary parasites of honey bees on several continents. Genetic analyses on Varroa indicating Varroa taxonomy and dispersal; Presentation of the complete mitochondrial sequence of the important honey bee pest Varroa destructor; How researchers described a dispersed set of several oligonucleotide primers that can be used to address genetic questions in Varroa; View that a subset of these primers should be useful for taxonomic and phylogenetic studies in other mites and ticks.

Inherited bacteria that kill male hosts early in their development are known from five insect orders. We ask to what extent the incidence of male-killers might be restricted by the rate at which new host–parasite interactions arise, by testing whether multiple male-killers have invaded a single host species. In Uganda, the butterflies Acraea encedon and A. encedana are both infected by the same strain of male-killing Wolbachia and there was no evidence of variation within the population. In Tanzanian A. encedon however, two phylogenetically distinct strains of male-killing Wolbachia were found within the same population. If this pattern of male-killer polymorphism is found to be general across infected species, it suggests that new male-killing infections arise frequently on an evolutionary time scale. Whether this polymorphism is stable, and what forces may be maintaining it, are unknown. [ABSTRACT FROM AUTHOR]

In parasitoid wasps, self-superparasitism (ovi-position into a host already parasitized by the female herself) often contributes less to the reproductive success of the parasitoid than oviposition into a host previously parasitized by a conspecific (conspecific superparasitism). It could therefore often be profitable for parasitoids to avoid self-superparasitism. This requires a mechanism for either ( 1 ) the avoidance of previously searched areas and/or (2) the rejection of hosts containing eggs laid by the searching female. We investigated whether the solitary parasitoid Epidinocarsis lopezi is able to avoid self-superparasitism. We show that visits to previously searched patches were shorter than visits to unsearched patches and conclude that E. lopezi females leave a trail odour on patches they have searched. No differences were found between the time on patches previously searched by the wasp itself and on patches visited by conspecifics. However, E. lopezi superparasitizes fewer hosts previously parasitized by itself than hosts parasitized by a conspecific. Thus, they recognize an individual-specific mark in or on the host. We discuss how patch marking and host marking enable E. lopezi to avoid self-superparasitism. [ABSTRACT FROM AUTHOR]

Females of the parasitic wasp Antrocephalus pandens can detect differences in the quality of their hosts (pupae of Corcyra cephalonica, a stored-product moth) and allocate offspring of either sex accordingly. Larger and younger hosts are accepted more often in both dead and live hosts; more female offspring emerge from the perceived better hosts, while more males emerge from the smaller, older ones. These patterns are consistent with a sex allocation strategy by the mother, since females from a given size host tend to be larger than males and larger females produce more eggs. However, when wasps lay their eggs in groups of hosts of different size and age rather than encountering them one at a time, no difference in number or sex ratio of offspring is detected between groups. This result and evidence from the change in offspring sex ratio with female age and with numbers of females foraging on a group of hosts are interpreted and discussed in the context of sex allocation (Charnov 1979) and local mate competition (LMC, Hamilton 1967) theories. [ABSTRACT FROM AUTHOR]

A survey was conducted in three main regions of Iraq to isolate and identify entomopathogenic and insect parasitic nematodes. Soil samples were collected from 15 sites across 3 provinces from grassland, date palm, and citrus fields, and tested for the presence of nematodes. Out of 100 samples collected, 2 isolates of nematodes were recognized. The collected specimens were characterized first morphologically and then by molecular studies to characterize and identify the isolates based on ITS and 18S rDNA genes. Both isolates were recovered from soil samples of citrus and palm orchards located in 3 regions in the city of Baghdad. The isolates were identified by analyzing sequenced results and then by DNA sequences that were blasted against the NCBI database in GenBank. The 2 isolates were separated into 2 genera, assigned as IRQ.1 and were identified as Heterorhabditis and IRQ.2, that was identified as Oscheius. Molecular analysis and phylogenetic relationship of both genera were analyzed, using the DNA sequences of 2 loci. The Heterorhabditis species was assigned as Heterorhabditis bacteriophora, while the Oscheius species was identified as Oscheius myriophilus. These species were the first to be reported in Iraq. [ABSTRACT FROM AUTHOR]

The article provides information on the parasitic infection brought about by malaria sporozoites. A study was conducted to examine the living pathogen inside tissues of hosts. It was found that after inoculation period, sporozoites migrate to liver cells to establish the first intracellular replicative stage. It is during erythrocytic stage that severe conditions of the disease occur.

Reports on a study of spiders and affect of parasitic wasp larva on their behavior and life span. Background regarding normal spider behavior and web-making patterns; Use of chemicals which allow the larva to control the spider and its behavior; Details regarding the creation of a cocoon for the larva and the subsequent death of the spider.

The article focuses on the parasitic heartworm which infects crickets and induces them to develop a death by drowning. In some manner, parasitic hairworm prompts its host to develop a death wish at the proper time if this hairworm is sexually mature and its host's timely death in a watery grave enables it to procreate. It is noted that hairworm initiates an erratic behavior in crickets as it grows mature.

The article focuses on some plants that are known to attract parasitic wasps to eat the eggs laid on them by insects. However, the exact mechanism of this complex behavior are not clear. It says that Nina Fatorous and her colleagues at Wageningen University in the Netherlands have determined that in one case, the mechanism is triggered by a specific compound in male insect ejaculate. In addition, the ejaculate of male large cabbage white butterflies contains anti-aphrodisiac benzyl cyanide to reduce female re-mating.

The article discusses the research on the horizontal gene transformation with analyzation on an intracellular bacterium called Wolbachia. The constrained intracellular bacterium Wolbachia is known for its ability to quickly invade insect populations utilizing a range of reproductive parasitic mechanisms. One of the mechanism is cytoplasmic incompatibility where sperm from Wolbachia-infected males is qualified so that it can fertilized eggs produced by females infected with same Wolbachia strain.