Insects Hymenoptera

The hymenopterous insects (Hymenoptera), to which the species-rich families of ants, honey-bees, wasps and bumble-bees belong, often live in large colonies and use pheromones to maintain their highly structured social order. 

Materials produced by crystalliferous bacilli which elicit a toxic response in susceptible insects may be separated into two types. The first type, the true toxins, include the crystalline protein inclusion body the parasporal body of Hannay (14)], a heat-stable, water-soluble exotoxin active against flies, a heat-stable, dialyzable water-soluble exotoxin, toxic to Lepidoptera on injection (23), and a heat-labile, water-soluble, filterable exotoxin, toxic toward larch sawfly larvae (Hymenoptera) which was reported by Smirnoff (31). 

Bonifazi F, Jutel M, Bilo BM. Bimbaum J. Muller U EAACI Interest Group on Insect Venom Hypersensitivity Prevention and treatment of Hymenoptera venom allergy guidelines for chnical practice. Allergy 2005 60 1459-1470. 

Hymenoptera venom is a prominent trigger of systemic reactions. Severe and fatal reactions have been described in patients with mastocytosis [9, 30, 31]. In few cases with urticaria pigmentosa and Hymenoptera venom anaphylaxis, no sensitization could be detected by means of skin tests and determination of specific IgE antibodies [32]. However, larger series found evidence that these systemic reactions are normally IgE-mediated insect sting allergies [7,33]. 

Diet should be modified only in cases where foods have been proven to elicit symptoms. Patients with mastocytosis and Hymenoptera venom exposure are at risk for severe anaphylaxis. Thus, specific immunotherapy should be considered in patients with Hymenoptera venom allergy and then administered under close supervision [31]. The majority of patients with mastocytosis reportedly tolerate immunotherapy without significant side effects and appear protected following this approach [33,40]. However, there does appear to be some increased risk for adverse reactions during initiation of immunotherapy, as well as for therapy failures [31, 33]. An increased maintenance dose of insect venom has been reported to carry better success rates by sting provocation [41]. Also, in the light of 2 fatal cases of anaphylaxis after discontinuation of SIT in patients with mastocytosis [30], lifelong immunotherapy should be considered [26]. 

One limitation of serum-specific IgE is that given the cross-reactivity between different Hymenoptera venoms, and also due to the presence of anti-carbohydrate antibodies, it is frequent to find several simultaneous positive results in patients with non-identified insect stings, a situation which makes diagnosis of the same difficult. In these cases, RAST inhibition and the release of histamine occasionally provide data on the venom involved and when this is not the case, it is advisable to administer immunotherapy against both [44]. 

Venoms causing anaphylaxis or other allergic reactions originate almost exclusively from social Hymenoptera, most often honeybees and vespids (fig. 1) [1], occasionally from bumble bees [2], in America [3] and in Australia [4], also from ants. Stings by other insects like mosquitoes, bedbugs, fleas, horse flies and midges can very rarely also cause systemic allergic reactions. These are however not due to venoms but to... 

We will concentrate in this chapter on venoms of social Hymenoptera which are certainly responsible for more than 99% of insect sting-induced anaphylaxis. 

While in anaphylaxis caused by other frequent elicitors like food and drugs, allergen-specific immunotherapy is not established, immimotherapy with Hymenoptera venoms has been shown to be effective in three prospective controlled trials (table 4) [38-40] and also in a number of studies where patients were submitted to a sting challenge with the responsible insect during venom immimotherapy (table 5) [44]. While over 90% of vespid venom-allergic patients are fully protected and do not develop any... 

Hoffman DR Hymenoptera venoms composition, standardization, stabihty in Levine MI, Lockey RF (eds) Monograph on Insect Allergy. Pittsburgh, Lambert Assoc, 2003, pp 37-53. 

Settipane GA, Newstead GJ, Boyd GK Frequency of Hymenoptera venom allergy in an atopic and normal population. J Allergy Clin Immunol 1972 50 146-150. Nall TM Analysis of 677 death certificates and 168 autopsies of stinging insects deaths. J Allergy Clin Immunol 1985 75 207. 

Abstract Hymenoptera is a very large and diverse insect order that includes the majority of both the social and the parasitic insects. With such diversity comes a variety and complexity of semiochemicals that reflect the varied biology of members of this order. This chapter reviews the chemical identification of pheromones and semiochemicals in the order Hymenoptera since 1990. For this review, the species in Hymenoptera have been classified as solitary, parasitic, or social. The chemical diversity of semiochemicals in Hymenoptera and future trends in pheromone identification are also discussed. 

All of the suborder Symphyta and many species in the superfamily Aculeata in the suborder Apocrita are solitary insects. Although not requiring the complex semiochemistry of parasitic or social insects, solitary insects employ pheromones for mating, territorial marking, and host marking. Unfortunately, very few of these have been chemically identified. The pheromones of sawflies and seed wasps were extensively reviewed in 1999 [ 14]. The semiochemicals recently identified in solitary hymenoptera, discussed below, are summarized in Table 2 and Fig. 1. 

Unlike parasitoids of other insect orders that have host-seeking larvae, most parasitic hymenoptera lay their eggs on, in, or very close to a host individual [11]. This requires the adult female to find a suitable host, often with the aid of chemical cues from host frass, pheromones, plant volatiles emitted upon host feeding or egg-deposition, silk, honeydew and other secretions. She may then chemically mark the host following oviposition to reduce superparasitism by herself or intra- and inter-specific insects [11]. 

Parasitic hymenoptera hold promise in integrated pest management schemes, because they parasitize many economically important insect pests in a species-and stage-selective manner. The pheromones and kairomones of the parasitic hymenoptera have been studied for a long time, and there are many examples where there is evidence of chemical mediation of parasitoid behavior. This review emphasizes work done since the last major reviews [11, 12, 42] and, where it is available, on the primary bioassay-guided chemical identification of the semiochemical (Fig. 2 and Tables 3 and 4). 

In Alloxysta victrix, 6-methylhept-5-en-2-one 16, which is produced by both males and females, was identified as potentially attractive to the males and slightly repellent to the females in Y-tube olfactometer assays [60]. In this study, the activity was also dependent on prior exposure of the insects to the compound. Naive insects responded more strongly than previously exposed ones. This underscores a second difficulty in the bioassay-guided identification of parasitoid hymenopteran pheromones the responses are very dependent on the context and on prior exposure. Learning has been demonstrated in several species of parasitic hymenoptera [61-65]. 

Most social insects are found in the order Hymenoptera. Sociality in insects is defined by the presence of one or more of the following traits (1) individuals of the same species cooperate in caring for the young (2) there is a reproductive division of labor, with usually sterile individuals working on behalf of fecund individuals and (3) there is an overlap of at least two generations in life... 

The repertoire of chemicals that can be used for communication is limited by the biosynthetic ability of the insect. Compared to other insect orders, pheromone biosynthesis in Hymenoptera has received little study [191]. However, the biosynthetic origins of chemically diverse hymenopteran semiochemicals likely include aromatic, fatty acid, and terpenoid pathways as well as simple modifications of host-derived precursors. Notable recent studies include the biosynthesis of the fatty acid components (2 )-9-oxodec-2-enoic acid 52 and (2 )-9-hydroxydec-2-enoic acid of the honeybee queen mandibular pheromone from octadecanoic acid [192,193], and the aliphatic alcohol and ester... 

With adequate resources and effort, the tools are available to chemically identify many more semiochemicals in Hymenoptera. Much is still to be understood about the chemically-mediated communication in this large and diverse insect order. In addition,because many hymenoptera are significant beneficial or pest insects, and the use of semiochemicals in the management and monitoring of insects is becoming standard, the identification of additional semiochemicals in Hymenoptera is an economically worthwhile endeavor. 

Pheromone identification is still difficult because the structure of unique compounds present in small amounts in mixtures of similar molecules has to be elucidated. This topic will be discussed in detail by Ando as well as by others, showing nicely the recent progress in analytical techniques. The following chapter by R. Jurenka deals with insect pheromone biosynthesis with special emphasis on lepidopteran pheromones and also covers genetic aspects. The subsequent chapter by C. Keeling et al. describes the hymenopteran semio-chemicals (bees and ants), describing pheromones and allelochemicals. The hymenoptera add a certain flavor to the scene, because now the complexity of social insects with their many interactions comes into play, as well as the multi-level (multi-trophic) signals used by parasitoids. 

OBPs were initially identified in Lepidoptera and later isolated and/or cloned from various insect orders, namely, Coleoptera, Diptera, Hymenoptera, and Hemiptera ([16] and references therein). Recently, they have been identified from a primitive termite species [ 17], thus, suggesting that this gene family is distributed throughout the Neopteran orders. The three orders most... 

Figure 7 Venomous hymenoptera insects, (a) Common honeybee (Apis me/Z/fera) (b), eastern yellowjacket Vespula maculifrons)-, (c) European hornet (Vespa crabro), (d) bull ant (Myrmecia esuriens)-, (e) Asian giant hornet (Vespa mandarinia japonica,)] (f) wasp stinger. Photos from (a) to (f) by Autan (Creative Commons Attribution ShareAlike License), E. Begin (Creative Commons Attribution ShareAlike License), N. Jones (Creative Commons Attribution ShareAlike License), Nuytsia (Creative Commons Attribution ShareAlike License), Netman (Creative Commons Attribution ShareAlike License), and M. Halldin (GNU free documentation license), respectively.

Results from these laboratory studies demonstrated that avermectin Bj had high toxicity for the twospotted spider mite (Tetranychus urticae) on bean plants. When applied in solution directly onto adult and nymphal spider mite populations on foliage, avermectin Bj was shown to be 50-200 times as potent as commercially available acaricides, with an LC q of 0.02-0.03 ppm. Additional tests on foliage with insects in the order Lepidoptera, Coleoptera, Homoptera, Orthoptera, Diptera, Isoptera and Hymenoptera confirmed the broad spectrum activity and potency of the avermectin family of compounds and avermectin Bj in particular. Table II provides LC q values for avermectin Bj for the control of larval forms of several of these insects in foliar residue assays (18). 

Allergic reactions (eg, bronchospasm, urticaria, pruritus, angioneurotic edema, or swelling of the lips, eyelids, tongue, and nasal mucosa) due to anaphylactic shock caused by stinging insects (primarily of the order Hymenoptera, that includes bees, wasps, hornets, yellow jackets, bumble... 

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