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Abstract: The parasitoid wasp Spalangia cameroni and the predatory beetle Pseudoophonus rufipes have long been studied for use as biological control agents against the Mediterranean fruit fly Ceratitis capitata, particularly in citrus fruit orchards. Nevertheless, these two species of natural enemies, when competing for a common resource, may experience intraguild predation (IGP) interactions. These possible interactions, affecting parasitism and predation, have been evaluated in the present work, under laboratory conditions, through potential changes in functional response. Regarding host/prey density, both natural enemies, when acting alone, showed a type II functional response. Nevertheless, due to IGP, S. cameroni, in the presence of P. rufipes, showed a higher fertility rate and a type III functional response. The parasitism behaviour of S. cameroni was affected by the presence of the predator, reducing the host handling time. Conversely, the parasitism rate of S. cameroni did not vary in the presence of P. rufipes but the degree of superparasitism decreased and led to an increased fertility rate and an increasingly female‐biased sex ratio. Meanwhile, the predatory efficiency of P. rufipes was not affected by the presence of S. cameroni but discrimination between parasitised and unparasitised pupae of C. capitata, with a preference for the latter, was reported for this predator species. Our results suggest that in biological control programmes, the use of only one of these species is recommended at low infestation levels, whilst at high densities of the pest, the combination of both natural enemies seems to be the most appropriate strategy. [ABSTRACT FROM AUTHOR]

The final instar larva of Synergus filicornis (Cameron) (Hymenoptera: Cynipidae: Synergini) is described and illustrated. Morphological structures of a diagnostic value are discussed. The most remarkable character states shown by the mature larva of this species lie in the integument, which unlike the rest of described cynipoid mature larvae, presents tegumental differentiations. Additionally the antennal orbits, unlike those of other described Synergini mature larvae, did not present one seta on each antennal orbit. The immature larvae can be differentiated from the mature larva by the following characters: a) number and location of sensorial tegumental differentiations on the head, b) number of sensilla on the maxillary palpi, and c) morphology of the mandibles. The determination of the mandibles size, in this species, permits the estimation of the larval stages number. [ABSTRACT FROM AUTHOR]

Parasitoid fitness strongly depends on the availability and quality of hosts, which provide all resources required for larval development. Several factors, such as host size and previous parasitation, may affect host quality. Because self-superparasitism induces competition among a female's offspring, it should only occur if there is an imperfect recognition of self-parasitized hosts or if there is a fitness advantage to self-superparasitism. Against this background, we investigated self-superparasitism and offspring production in Spalangia cameroni (Hymenoptera: Pteromalidae) in relation to the abundance of a novel host, Ceratitis capitata (Diptera: Tephritidae). Individual pairs of parasitoids were provided with either two (low host abundance) or ten (high host abundance) pupae per day. Under high host abundance, lifetime fecundity (number of eggs laid), offspring number, number of pupae parasitized and hosts killed were greater than under low host abundance, whereas the number of eggs per host was lower; and the proportion of hosts that did not produce offspring tended to be lower. The latter suggests the occurrence of ovicide, when hosts are scarce due to an at least imperfect recognition of previously self-parasitized hosts. Offspring production per parasitized pupa was higher when hosts were scarce and levels of self-superparasitism high, suggesting the existence of beneficial effects of self-superparasitism. [ABSTRACT FROM AUTHOR]

The frequency of superparasitism and its effects on the quality of laboratory-reared Spalangia cameroni (Hymenoptera: Pteromalidae) parasitoids were investigated under laboratory conditions. Numerous variables were measured, such as the number of ‘ovip holes’ per host as a measure of superparasitism. Adult emergence and sex ratio, as well as female size, emergence ability from soil and longevity were also measured. Finally, an assessment was made of fertility and survival of adult parasitoids emerging from the medfly Ceratitis capitata (Diptera: Tephritidae) pupae with different levels of superparasitism. A high frequency and prevalence of superparasitism under laboratory rearing conditions was observed. The number of ‘ovip holes’ per host ranged from one to 17, with an average (±SD) of 2.8±3.4. Sex ratios became increasingly female-biased with increasing levels of superparasitism, although overall levels of wasp emergence (male, female) declined. Nevertheless, no relationship was discerned between female size and level of superparasitism. The ‘emergence ability from the soil’ was higher in those parasitoids that emerged from strongly superparasitized hosts, but not related to the type of substrate in which the host pupae were buried. The level of superparasitism did not have a significant effect on the longevity, fertility and survival of female parasitoids. Our results support the hypothesis that superparasitism in S. cameroni might be adaptive, since attributes such as ‘emergence ability from the soil’, longevity, fertility and survival were not affected by the level of superparasitism or the presumably detrimental effects derived from physical combats among conspecific larvae. Our findings are relevant to recommendations for rearing S. cameroni for biological control releases, as well as shedding light on superparasitism under both laboratory and field conditions. [ABSTRACT FROM PUBLISHER]

In the present study, the mating behaviour of the velvet ant Nemka viduata (Pallas) (Mutillidae) is described both from field and laboratory observations. The whole pairing interaction, lasting around two hours, includes several behavioural phases. During pre-copula, the male seizes the female's neck with his mandibles, and then starts to rhythmically stroke the prothorax of the female with his forelegs (this behaviour is also resumed after copulation) before curving his abdomen in order to couple the genital parts, including genital armatures (the male parameres remaining outside the female body); just prior to copulation, the female extrudes the sting, and immediately after copulation begins, she stridulates for 7-10 s, this behaviour is repeated when the pair separates. During copulation (lasting around two minutes), the male moves his antennae rhythmically, hitting the back of the female's head with the scape. Generally, recently-mated males become aggressive towards females, but more tolerant after a few days. During the whole pairing act, females are held by the males' mandibles, and in the field they are carried off in flight or by walking to a safe place to copulate. This would suggest that larger males, which can lift a wider range of female sizes, have a reproductive advantage, as indicated by data obtained on their load-lifting capacity with respect to the size distribution of females. A review of mating behaviour in mutillid wasps and comparisons with other lineages of aculeate and non-aculeate Hymenoptera are also given. [ABSTRACT FROM AUTHOR]

In this work, we study the suitability of using dead medfly Ceratitis capitata pupae, killed by heat- or cold-shock, for the mass rearing of Spalangia cameroni, a pupal parasitoid of key pests. 100% mortality of medfly pupae could be accomplished with cold-shock at –20°C for 60 min or with heat-shock at 55°C for 30 min. Neither parasitism percentage nor sex ratio of the offspring differed significantly among heat-shocked, cold-shocked and untreated pupae. In addition, there was no significant difference in the percentage of parasitoids that aborted (♂♂ or ♀♀) among pupal treatments. Some of the pupae were covered with peat because the third larval instar of the medfly buries itself before pupation. However, the buried pupae were not parasitised at a greater or lesser rate than those not covered with peat. The percentage of parasitism was also unaffected by whether the pupae had been killed recently or had been stored at between 4°C and 6°C over 15 or 30 days. The use of dead hosts and later storage permitted the following: (a) the use of hosts over long periods of time; (b) a rapid increase in parasitoid numbers and (c) the availability of pupae killed at the most suitable postpupation times for the production of parasitoids. Furthermore, in biological control projects, the use of dead parasitised pupae in the field avoids the risk of enhancing the pest and allows an increase in parasitism in the field through the use of pupae treated with cold- or heat-shock. [ABSTRACT FROM AUTHOR]

Territorial and agonistic behaviour in male sand wasps (Stizus continuus) was investigated in order to determine the influence of body size on territory maintenance and the strategies used to reduce the costs associated with territoriality. Size is the decisive factor in the capacity of males to defend a territory against other competitors: (1) in the disputes observed, the largest male was usually the winner; (2) territorial males were larger than those never seen occupying territories; (3) the size of males occupying territories that were left vacant when their inhabitants were removed experimentally was smaller. To optimize their territorial behaviour, males only defend sites in the nesting area and only when virgin females are emerging (from 0700 to 1300), and reduce the time spent perching (as opposed to patrolling) as temperature increases during the morning. To reduce costs associated with contests, males fight only with rivals of similar size and show a greater tendency to fight with larger males when virgin females are most likely to emerge (from 0800 to 1000). This suggests that males may be able to estimate the size of rivals immediately before an attack (face-to-face hovering), and leave when the opponent is significantly larger. [ABSTRACT FROM AUTHOR]

We studied the nesting behaviour and provisioning of Bembix merceti Parker and Bembix zonata Klug during three flight seasons (1993-1995). The females of B. merceti capture Diptera from seven different families to feed their larvae. Provisioning is progressive. The females provide a greater number of prey over subsequent days during larval growth. This activity begins increasingly earlier and lasts for longer, and prey capture is increasingly faster. Although the activity of the females is greater during the middle hours of the day, towards the end of each day the number of prey per wasp increases slightly and the duration of provisioning flights is reduced. Regarding Bembix merceti , we also report on nest structure and excavation as well as about the different natural enemies of these wasps. The data recorded for B. zonata refer to nest digging and structure, the wasps' natural enemies and their provisioning strategies, which in general are similar to those seen for the females of B. merceti . [ABSTRACT FROM AUTHOR]

Bembix merceti, a central-place forager that captures dipterans to feed its larvae, could be considered a suboptimal forager. The females tend to optimize their provisioning flights, capturing prey in proportions different from those present in the surrounding environment. These wasps make a positive selection of families of flies with greater mean weights even though they are less abundant and, within the families whose weight is not too great, capture individuals whose weight is larger than the mean. Selection is based on prey size and not on the type (family) to which the prey belongs. A significant correlation between the weight of each female and the weight of the largest prey captured by the wasp was found, suggesting that the females capture prey in consonance with their lift capacity. Nevertheless, captures were not optimized maximally; the females maintained a margin with respect to the maximum prey weights that they could transport efficiently. This margin could be related to the low availability of large prey in the environment; to the type of progressive provisioning shown by the females of this species; and to other factors, such as the good manoeuvrability of their prey and the pressure from their natural enemies and congeners. [ABSTRACT FROM AUTHOR]

Examines the systematics and larval morphology of the European Ampulex jurine of order Hymenoptera, family Sphecidae. Differences with Ampulex fasciata; Geographical distribution.

Abstract: The larval–pupal endoparasitoid Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is currently the most commonly employed biological control agent against Tephritid fruit flies in the Americas. However, this parasitoid remains largely ignored and is not used in many regions, including the Mediterranean Basin. In this study, the potential of D. longicaudata as a biocontrol agent against the Mediterranean fruit fly (medfly) Ceratitis capitata (Diptera: Tephritidae) was addressed in an area of eastern Spain (the Valencian community). The parasitic activity of parasitoids and the effects of climatic conditions were evaluated throughout a 1‐year period in field‐cage experiments in which parasitoids were confined with apples artificially infested with medfly larvae. The following parameters were calculated and related statistically to several environmental conditions: the parasitism rate, the induced mortality and progeny sex ratio. The results show that D. longicaudata is able to parasitize medfly larvae throughout the year under semi‐natural conditions. Important fluctuations in the parasitism rate (from almost zero to 42%) and the induced mortality (from 6% to 80%) were partially influenced by climatic conditions. The parasitism rate increased with mean temperature and decreased with mean relative humidity, while the induced mortality decreased with minimum relative humidity. The optimal climatic conditions for the activity of the parasitoid were a mean temperature of 16–24°C combined with a relative humidity of 45%–60%. Overall, these results suggest that reduction in the medfly population due to D. longicaudata activity is feasible and provide information about the optimal time period for parasitoid release in the field. In conclusion, D. longicaudata has a significant potential to control C. capitata in the Mediterranean region. [ABSTRACT FROM AUTHOR]

The aetiology of idiopathic scoliosis (IS) remains unknown, but there is growing support for the possibility of an underlying neurological disorder. Functional magnetic resonance imaging (fMRI) can characterize the abnormal activation of the sensorimotor brain network in movement disorders and could provide further insights into the neuropathogenesis of IS. Twenty subjects were included in the study; 10 adolescents with IS (mean age of 15.2, 8 girls and 2 boys) and 10 age-matched healthy controls. The average Cobb angle of the primary curve in the IS patients was 35° (range 27°-55°). All participants underwent a block-design fMRI experiment in a 1.5-Tesla MRI scanner to explore cortical activation following a simple motor task. Rest periods alternated with activation periods during which participants were required to open and close their hand at an internally paced rate of approximately 1 Hz. Data were analyzed with Statistical Parametric Mapping (SPM5) including age, sex and laterality as nuisance variables to minimise the presence of bias in the results. Compared to controls, IS patients showed significant increases in blood oxygenation level dependent (BOLD) activity in contralateral supplementary motor area when performing the motor task with either hand. No significant differences were observed when testing between groups in the functional activation in the primary motor cortex, premotor cortex and somatosensory cortex. Additionally, the IS group showed a greater interhemispheric asymmetry index than the control group (0.30 vs. 0.13, p < 0.001). This study demonstrates an abnormal pattern of brain activation in secondary motor areas during movement execution in patients with IS. These findings support the hypothesis that a sensorimotor integration disorder underlies the pathogenesis of IS. [ABSTRACT FROM AUTHOR]

The aetiology of idiopathic scoliosis (IS) remains unknown, but there is growing support for the possibility of an underlying neurological disorder. Functional magnetic resonance imaging (fMRI) can characterize the abnormal activation of the sensorimotor brain network in movement disorders and could provide further insights into the neuropathogenesis of IS. Twenty subjects were included in the study; 10 adolescents with IS (mean age of 15.2, 8 girls and 2 boys) and 10 age-matched healthy controls. The average Cobb angle of the primary curve in the IS patients was 35° (range 27°-55°). All participants underwent a block-design fMRI experiment in a 1.5-Tesla MRI scanner to explore cortical activation following a simple motor task. Rest periods alternated with activation periods during which participants were required to open and close their hand at an internally paced rate of approximately 1 Hz. Data were analyzed with Statistical Parametric Mapping (SPM5) including age, sex and laterality as nuisance variables to minimise the presence of bias in the results. Compared to controls, IS patients showed significant increases in blood oxygenation level dependent (BOLD) activity in contralateral supplementary motor area when performing the motor task with either hand. No significant differences were observed when testing between groups in the functional activation in the primary motor cortex, premotor cortex and somatosensory cortex. Additionally, the IS group showed a greater interhemispheric asymmetry index than the control group (0.30 vs. 0.13, p < 0.001). This study demonstrates an abnormal pattern of brain activation in secondary motor areas during movement execution in patients with IS. These findings support the hypothesis that a sensorimotor integration disorder underlies the pathogenesis of IS. [ABSTRACT FROM AUTHOR]

Primary objective: To determine the neuropsychological profile of persons with anoxic brain injury.Methods and procedures: A retrospective study on a population of persons with anoxic brain injury admitted to a Brain Injury Unit (Institut Guttmann, Spain) from 1995–2003. The sample was divided according to physiopathological mechanisms in two sub-groups: ischemic anoxia (21 cases) and hypoxemic anoxia (11 cases). Functions assessed included orientation, attention, language, visuo-perceptive and visuo-constructive processing and verbal memory.Results: Neuropsychological assessment showed diffuse cognitive impairment in all assessed functions. Episodes of ischemic anoxia caused more severe verbal memory and learning problems than episodes of hypoxemic anoxia.Conclusions: This study shows that memory problems are the most prominent and relevant impairment, although all other cognitive functions are also impaired, affecting both memory itself and general behaviour. Statistical analysis also provides preliminary evidence on the different profile of memory impairment whether cerebral anoxia had hypoxic or ischemic origin. [ABSTRACT FROM AUTHOR]