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This note reports the first finding of the reduviid bug Nagusta goedelii (Kolenati, 1857) in Sardinia and is first ascertained case of the human-mediated introduction of this species. In fact, Nagusta goedelii is showing an expansion of its geographical range from the east to the west, however the causes are still unknown and further studies are needed. A brief review of the European distribution of this species is given. An update of its regional occurrence in Italy, based on verified records available online, is also provided. The species was observed in co-occurrence with the invasive bug Halyomorpha halys (Stål, 1855), which would appear to be one of its possible predators.

Type specimens of Neotropical Chrysopidae are currently held in two Italian natural history museums. Four are in the Museo Regionale di Scienze Naturali (MRSN), Torino, and five are in the Museo Civico di Storia Naturale “Giacomo Doria” (MSNG), Genova. Together, these nine specimens also represent all of the known New World types of Chrysopidae housed in Italian museums. All were described by Longinos Navas between 1922 and 1932, and all are now in relatively good condition. Here, we catalog and provide images of each specimen, designate lectotypes, and offer current taxonomic and nomenclatural information on the species represented by each. Two nomenclatural changes are proposed: (1) Chrysopa mainerii Navas, 1929, previously considered incertae sedis, is synonymized with Ceraeochrysa everes (Banks, 1920), n. syn.; (2) Chrysopa barberina Navas, 1932, also previously incertae sedis, is identified as Chrysoperla barberina (Navas, 1932), n. comb.

Dryocosmus kuriphilus Yasumatsu (Hymenoptera Cynipidae) was first recorded in Sardinia (Italy) in 2007. Two years later a biological control program started with the introduction of its non-native parasitoid, Torymus sinensis Kamijo (Hymenoptera Torymidae). Over a nine-year period (2009–2017), data on the relative abundance of D. kuriphilus, its native parasitoids and T. sinensis were collected. Native parasitoids reacted quickly to the large availability of hosts. However, a dramatic change in the abundance of each native species was recorded from year to year. In the first few years, the native parasitoid community and pest abundance did not fluctuate much. The turning point was 2014, when, at the same time, the native parasitoid populations increased and the T. sinensis populations also began to increase. In the following year, both the D. kuriphilus and native parasitoid populations decreased considerably, whereas the T. sinensis populations reached over 50% parasitism. The univoltine D. kuriphilus acted as an asynchronous resource for native bivoltine parasitoids. An asynchronous host-parasitoid interaction produces wide fluctuations in their populations. In this case, D. kuriphilus strongly altered the local community, which was subjected to a chaotic change in composition and species abundance. When T. sinensis became established, it monopolized the pest, making this resource unavailable to native parasitoids that returned to attack almost exclusively the native oak cynipids. In fact, the successful control of D. kuriphilus by the introduction of T. sinensis rebalanced the situation that had been altered by the arrival of the invasive pest.

We present a discrete-generation model to study the effect of a seasonally asynchronous alien host on the population dynamics of a native host/parasitoid system. We assume that i) the native host and parasitoid are seasonally synchronous; ii) there is no direct competition for resources between the two host species (one native, one alien); and iii) the introduced alien host population (the alternative host) is in an invasive stage and, consequently, it is not subject to any density-dependent regulation. In our model, variations in the annual number of generations (voltinism) of the alien host greatly alter the dynamics of the native host/parasitoid interaction. When the alien host is synchronous with the native host, the parasitoid is favoured, and the native host population decreases until reaching a new, lower equilibrium or becoming extinct. By contrast, when alien and native hosts are asynchronous with each other, there are population oscillations of the native community members compatible with the pulsating availability of the alien host and, under specific conditions, the parasitoid may rapidly become extinct.

Cyclodextrins have many advantages when used in the agricultural field as complexes with agrochemicals. However, they interact with molecules and biological systems at different levels and an enhancement of agrochemical effectiveness even as a physical mixture cannot be ruled out. This was verified for the first time by a simple experimental system with mealworm larvae (Tenebrio molitor L.) as the pest, the inhibitor of chitin synthesis diflubenzuron as the insecticide, and beta-cyclodextrin as the adjuvant. Under laboratory conditions, mealworm mortality was recorded under the following three treatments: (i) neat diflubenzuron, (ii) diflubenzuron/beta-cyclodextrin physical mixture, and (iii) commercial formulation Dimilin WP25. The physical mixture with beta-cyclodextrin significantly increased the mortality by enhancing the effectiveness of diflubenzuron. A significant dose effect was also found. Considering the application protocol, this result may be more likely due to the bioavailability enhancement of diflubenzuron by beta-cyclodextrin. On the basis of the current knowledge and available literature, we assume that these results could be explained by the interactions between CDs and biological membranes and the associated increase in their permeability. The use of beta-cyclodextrin in physical mixtures with insecticides could be of interest in the development of more effective agrochemicals through simpler and less costly research processes.

Dear Editor,Although, most spiders in Italy basically have venom that is harmless to humans, one must consider some potentially dangerous species. Latrodectus tredecimguttatus (Rossi, 1790), also k...

Cardoon (Cynara cardunculus var. altilis) has gained interest as a novel crop for bioenergy, multipurpose uses, and industrial bio‐based productions, also based on the achene yield. However, achenes can be affected by various insects, which are considered as minor pests in traditional Cynara crops. Nonetheless, very little information is available on these pests. The aim of this research was to identify the frequency of different insect species with particular regard to weevils, and to quantify the achene yields and losses caused by these spermophagous insects on cardoon. Field measurements were performed across three consecutive years in Sardinia (Italy). Mature cardoon heads of different insertion orders (primary, secondary, tertiary and quaternary heads, respectively) were manually harvested. For each head, the achenes were counted and weighed, and bare receptacles were scored in terms of damaged areas by weevil larvae (i.e., the percentage of total area). The results highlighted a higher frequency of Larinus scolymi (90%) compared to Larinus cynarae. The total number of achenes per head and the 1000‐achene weight were markedly affected by head order. Actual achene yield ranged from 86.8 to 107.9 g per plant. The estimates of achene yield losses per plant due to Larinus weevils ranged from 36.3 in 2014 to 113.0 g per plant in 2015, corresponding to about 0.4 to 1.1 t per hectare, respectively. Our results showed that achene losses were caused mainly by L. scolymi, indicating that cardoon crop profitability could be jeopardised in the absence of insect controls. Based on the experimental data, appropriate strategies aimed at controlling weevil infestations are needed to preserve cardoon achene yields.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), spotted-wing drosophila, has recently become a common and serious pest of temperate fruit crops (small fruits, cherries and kaki) in many countries [1]. Crop damage is caused when adult females, using a serrated ovipositor, lay eggs in ripe and partially ripe fruit before harvest. Developing larvae cause soft and unmarketable fruit, moreover oviposition wounds provide access to pathogens that may enhance fruit deterioration leading to increased risk of secondary rot infections with an economic loss up to 80%. Push-pull strategies (stimulus deterrent diversionary strategies) attempt to reduce crop injury by modifying pest distribution using adversative stimuli to push the pest organism away from the crop while also using attractive stimuli to pull the pest organism out of the crop [2]. A novel and more sustainable method for repelling D. suzukii was evaluated by spraying edible repellents (alone and in mixture) on fruit surface during ripening period in combination with conventional natural attractive traps.