Cuticular hydrocarbons of Drosophila birchii and D. serrata: identification and role in mate choice in D. serrata

The cuticular hydrocarbon compositions of two sympatric species of Australian Drosophila in the montium subgroup of the melanogaster group that use cuticular hydrocarbons in mate recognition have been characterized. Drosophila birchii has 34 components in greater than trace amounts, with a carbon number range of C₂₀ to C₃₃. Drosophila serrata has 21 components above trace level and a carbon number range of C₂₄ to C₃₁. These two species share eight hydrocarbon components, with all but two of them being monoenes. For both species, the (Z)-9-monoenes are the predominant positional isomer. The hydrocarbons of D. birchii are n-alkanes, n-alkenes (Z)-5-, (Z)-7-, (Z)-9-, and (Z)-11-), low to trace levels of homologous (Z,Z)-7,11- and (Z,Z)-9,13-dienes; and trace amounts of (Z,Z)-5,9-C_25:2, a major component of D. serrata. Only one methyl branched hydrocarbon was detected (2-methyl C₂₈), and it occurred at very low levels. The hydrocarbons of D. serrata are dominated by a homologous series of (Z,Z)-5,9-dienes, and notably, are characterized by the apparent absence of n-alkanes. Homologous series of (Z)-5-, (Z)-7-, and (Z)-9-alkenes are also present in D. serrata as well as 2-methyl alkanes. Drosophila serrata females display strong directional mate choice based on male cuticular hydrocarbons and prefer D. serrata males with higher relative abundances of the 2-methyl alkanes, but lower relative abundances of (Z,Z)-5,9-C_24:2 and (Z)-9-C_25:1.     

Cuticular hydrocarbons of the eastern subterranean termite,Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae)

Major cuticular hydrocarbon components in several castes ofReticulitermes flavipes (Kollar) have been identified and quantitated. Types of hydrocarbons present includen-alkanes, 2-methylalkanes, 3-methylalkanes, 5-methylalkanes, an alkene, and an alkadiene, with a range in carbon numbers from C₂₁ to C₂₆, This is the first report on insect cuticular hydrocarbons in which both 2- and 3-methylalkanes are present, as well as the first report of an insect with a conjugated alkadiene.     

Cuticular Hydrocarbons of Buffalo Fly, <Emphasis Type="Italic">Haematobia exigua</Emphasis>, and Chemotaxonomic Differentiation from Horn Fly, <Emphasis Type="Italic">H. irritans</Emphasis>

We determined the quantity and chemical composition of cuticular hydrocarbons of different strains, sexes, and ages of buffalo flies, Haematobia exigua. The quantity of cuticular hydrocarbons increased from less than 1 μg/fly for newly emerged flies to over 11 μg/fly in 13-d-old flies. The hydrocarbon chain length varied from C₂₁ to C₂₉, with unbranched alkanes and monounsaturated alkenes the major components. Newly emerged flies contained almost exclusively C₂₇ hydrocarbons. Increasing age was accompanied by the appearance of hydrocarbons with shorter carbon chains and an increase in the proportion of alkenes. 11-Tricosene and 7-tricosene were the most abundant hydrocarbons in mature H. exigua. Cuticular hydrocarbons of H. exigua are distinctly different from those of horn flies, Haematobia irritans. The most noticeable differences were in the C₂₃ alkenes, with the major isomers 11- and 7-tricosene in H. exigua and (Z)-9- and (Z)-5-tricosene in H. irritans, respectively. Cuticular hydrocarbon analysis provides a reliable method to differentiate the two species, which are morphologically difficult to separate. The differences in cuticular hydrocarbons also support their recognition as separate species, H. exigua and H. irritans, rather than as subspecies.     

Cuticular hydrocarbons and defensive compounds ofReticulitermes flavipes (Kollar) andR. santonensis (feytaud): Polymorphism and chemotaxonomy

Colonies ofReticulitermes flavipes andR. santonensis were collected from the southeastern United States (Georgia) and the southwest of France (Charente-maritime). Defensive compounds and cuticular hydrocarbons were identified by gas chromatography-mass spectrometry and quantified by gas chromatography using an internal standard for each caste and all colonies. These analyses show that although the cuticular hydrocarbons ofR. santonensis in Europe andR. flavipes in Georgia are identical, their relative proportions are different. However, the defensive compounds synthesized by their soldiers are different. A strong chemical polymorphism between sympatric colonies ofR. flavipes in the SW United States was detected in terms of both the hydrocarbons of the workers and soldiers and in the defensive secretions of the soldiers. The six defensive secretion phenotypes are based on the presence or absence of terpenes whereas the cuticular hydrocarbon phenotypes are based on significant differences in the proportions of the various components. A multivariate analysis (analysis of principal components) clearly permitted discrimination of four phenotypes (three inR. flavipes and one inR. santonensis) without intermediates. The hydrocarbons responsible for these variations were identified, and it was shown that the variations are neither seasonal nor geographic. The phenotypes of the cuticular hydrocarbons (workers and soldiers) and defensive compounds are linked in each colony, forming in three groups inR. flavipes Georgia, one subdivided into four subgroups according to the defensive secretion phenotypes. The role of these polymorphisms is discussed and ethological tests indicate that the chemical polymorphism do not determine aggressive behavior. The taxonomic significance of these results is considered and two hypothesis are formulated: (1) We only detected a strong genetic polymorphism in one unique species, and we believe thatR. santonensis was introduced into Europe in the last century from oneR. flavipes colony. (2) Chemical variability characterizes the sibling species that can be grouped into the same subspeciesR. flavipes. Unknown mechanisms of reproductive isolation separate them.     

Role of cuticular hydrocarbons of aphid parasitoids in their relationship to aphid-attending ants

Lysiphlebus cardui, the dominant aphidiid parasitoid of the black bean aphid,Aphis fabae cirsiiacanthoidis (Afc), on creeping thistle, is able to forage in ant-attended aphid colonies without being attacked by ants. Several behavioral observations and experimental studies led to the hypothesis thatL. cardui mimics the cuticular hydrocarbon profile of its host aphid. Chemical analysis of the cuticular extracts revealed that bothL. cardui and Afc exclusively possess saturated hydrocarbons:n-alkanes, monomethyl (MMA), dimethyl (DMA), and trimethyl alkanes (TMA). Comparison of the hydrocarbon profiles of parasitoid and aphid showed great qualitative resemblance between parasitoid and host:L. cardui possesses almost all host-specific compounds in addition to species-specific hydrocarbons of mainly higher molecular weight (>C₃₀). However, there is a lesser quantitative correspondence between parasitoid and host aphid. Furthermore, we analyzed the cuticular hydrocarbon profile of another parasitoid of Afc,Trioxys angelicae. This aphidiid species is vigorously attacked and finally killed by honeydewcollecting ants when encountered in aphid colonies. Its cuticular hydrocarbon profile is characterized by the presence of large amounts of (Z)-11-alkenes of chain lenghts C₂₇, C₂₉, C₃₁, and C₃₃, in addition to alkanes and presumably trienes. The role of the unsaturated hydrocarbons onT. angelicae as recognition cues for aphid-attending ants is discussed.     

Biological activity of synthetic hydrocarbon mixtures of cuticular components of the female housefly (Musca domestica L.)

Mixtures of (Z)-9-alkenes (C₂₁-C₃₃),n-alkanes (C₂₁-C₃₃), and mono- and dimethylalkanes (C₂₇, C₂₉), as components of the cuticular lipids washed from the female housefly (Musca domestica L.), were synthesized and assayed for their biological activity on male houseflies. The (Z)-9-alkenes and their hydrogenatedn-alkanes were synthesized from jojoba wax components by the appropriate chain elongation. The methylalkanes were prepared by Grignard coupling reaction of the appropriate alkyl halides, catalyzed by Li₂CuCl₄. Six- to 7-day-old virgin male houseflies exhibited the highest mating strike activity toward 6- to 7-day-old virgin females. The mating strike activity of the synthetic hydrocarbons was studied by exposing 6- to 7-day old virgin males to petrol-ether-rinsed 1 to 2-day-old dead females treated with these chemicals. (Z)-9-Tricosene was the most active hydrocarbon tested when it was applied in amounts of 10 g to a washed dead female. Amounts of 5 g of (Z)-9-tricosene did not cause sexual activity in the males. Mixture of (Z)-9-alkenes showed low activity when applied at 10-g amounts. However, when mixtures were made of 5 g of (Z)-9-tricosene with 5 fig of each of certain mixtures of (Z)-9-alkenes, the striking activity became as high as that of 10 g of (Z)-9-tricosene. This might be a synergism effect. The mixtures ofn-alkanes, as well as the mono- and dimethylalkanes, showed moderate activity. When (Z)-9-tricosene was added to these materials no increase in male activity was observed.     

Contents of dufour glands of workers of three species ofTetramorium (Hymenoptera: Formicidae)

The Dufour glands of worker ants ofTetramorium caespitum, and the morphologically similarT. impurum are filled with similar, but species-specific mixtures of linear hydrocarbons and three homologous sesquiterpene corhpounds. Glands of workers ofT. caespitum contain, on average, 70 ng of oil containing C₁₃ to C₁₇ linear hydrocarbons withn-pentadecane (64%) and a mixture of pentadecenes (14%) as major components.T. impurum glands are smaller and contain an average of 40 ng of the same mixture but withn-pentadecane (49%) and a sesquiterpenoid compound (19%) the major components. Two isomeric pentadecenes, (Z)-6-pentadecene and (Z)-7-pentadecene are present in both species.T. semilaeve workers contain on average only 30 ng of a simple mixture of hydrocarbons with pentadecane contributing more than 90% of the total.     

Sex pheromone components of three species ofSemiothisa (Geometridae), (Z,Z,Z)-3,6,9-heptadecatriene and two monoepoxydiene analogs

Adult males ofSemiothisa signaria dispuncta (Walker) were attracted to field traps baited with (Z,Z,Z)-3,6,9-octadecatriene and (Z,Z)-6,9-cis-3,4-epoxy-octadecadiene. However, analyses of sex pheromone gland extracts of females of this species by GC-MS and by GC in combination with an electroantennograph detector (GC-EAD) showed the pheromone to be comprised of a mixture of the next lower homologs: (Z,Z,Z)-3,6,9-heptadecatriene and (Z,Z)-6,9-cis-3,4-epoxy-heptadecadiene. Blends of these two C₁₇ compounds were subsequently found to be more attractive to males in the field than the corresponding C₁₈ mixtures. Sex pheromones of two otherSemiothisa species were also found to contain C₁₇ components. (Z,Z,Z)-3,6,9-Heptadecatriene, detected by GC-EAD analysis of a female abdominal tip extract ofS. bicolorata (Fabricius), attracted conspecific males, and this attraction was significantly reduced by additions of (Z,Z)-6,9-cis-3,4-epoxyheptadecadiene, the major pheromone component ofS. signaria dispuncta, to the lure. (Z,Z)-3,9-cis-6,7-Epoxy-heptadecadiene was detected by GC-EAD analysis as the primary male antennal stimulatory component present in abdominal tip extracts ofS. ulsterata (Pearsall), and males of this species were attracted to traps baited with this epoxide. Each of these three C₁₇ compounds constitute previously unknown lepidopteran sex pheromone components. Blends of (Z,Z, Z)-3,6,9-heptadecatriene and (Z,Z)-3,9-cis-6,7-epoxyheptadecadiene attracted males of a fourth species,S. delectata Hulst, but no females of this species were obtained to permit analysis of its sex pheromone. The occurrence of (Z,Z,Z)-3,6,9-heptadecatriene inS. neptaria (Guenee) females was indicated by GC-MS analysis of an abdominal tip extract; however, no males were attracted to any of the fielded mixtures containing this hydrocarbon.     

Polyunsaturated hydrocarbons in the stable fly

Three triply-unsaturated hydrocarbons were identified from cuticular lipids of male and mixed-sex stable flies,Stomoxys calcitrans. The major compound, (Z,Z)-1,7,13-pentacosatriene, and two minor compounds, (Z,Z)-1,7,13-tetracosatriene and (Z,Z)-1,7,13-tricosatriene, were synthesized. Samples of male and female stable flies that differed in age, seasonality, geographic origin, rearing conditions of adults, and methods of extraction were analyzed for the presence of these triolefins. Females were found to have small quantities of the same C₂₅ triolefin, which appeared to be identical to that in males. No evidence was seen for attraction of males or females to natural or synthetic triolefins.Mention of a proprietary or commercial product does not constitute an endorsement by either the U.S. Department of Agriculture or the University of Florida.     

Mating stimulant pheromone and cuticular lipid constituents ofFannia femoralis (Stein) (Diptera: Muscidae)

The cuticular lipids of male and femaleFannia femoralis were similar for recently emerged insects but soon began to develop chromatographic patterns characteristic of each sex. Mature females contained more C₃₁ and C₃₃ monoolefin in the cuticular lipid than males. Also, the double bonds in the monoolefins of the female lipid were situated predominantly at the eleventh and thirteenth carbons, while most of those from the males were centrally located in the molecule or at the ninth carbon.The female C₃₁ monoolefin stimulated copulation by the males, but more mating activity occurred when the saturated hydrocarbons present in the female cuticular lipids were added. The synthetic monoolefin most active as a mating stimulant pheromone was (Z)-11-hentriacontene, but the addition of female alkanes or of syntheticn-alkanes to (Z)-11-hentriacontene increased the activity of the synthetic pheromone.A portion of a dissertation intended for submission by the first author to the Graduate School of the University of Maryland in partial fulfillment of the requirements for the Ph.D. degree.Mention of a proprietary or commercial product in this paper does not constitute an endorsement of this product by the U.S. Department of Agriculture or the University of Maryland.     

Cuticular hydrocarbons ofAedes hendersoni cockerell andA. triseriatus (SAY)

Field-caught adult male and femaleAedes hendersoni are difficult to distinguish from the sibling speciesA. triseriatus. We found that mosquitoes from the same sex of the sibling species can not be readily separated either by unique cuticular hydrocarbon components or by differences in percent composition of those components. Multivariate analysis of the cuticular hydrocarbon data does not provide good separation. Cuticular hydrocarbons were identified using gas chromatography electron-impact mass spectrometry and gas chromatography chemical-ionization mass spectrometry. Flame-ionization capillary gas chromatography was used for quantitative analysis of individual mosquitoes. Sixty-four hydrocarbons with chain lengths from C₁₆ to greater than C₄₆ were common to both species. Identified hydrocarbon components weren-alkanes, monomethylalkanes, dimethylalkanes, trimethylalkanes, and alkenes.Diptera: Culicidae.     

Pheromones of two arctiid moths (Creatonotos transiens andC. gangis)

The two major components of the female sex pheromones of twoCreatonotos species have been identified as an achiral C₂₁ triene, (Z,Z,Z)-3,6,9-heneicosatriene, and a chiral epoxide, (Z,Z)-2(2,5-octadienyl)-3-undecyloxirane. The ratios of these components in the two species fall into nonoverlapping ranges. Two additional achiral minor components, (Z,Z)-6,9-heneicosadiene and (Z,Z,Z)-3,6,9-tricosatriene, were also identified in the female sex gland extracts. The male pheromone of both species consists of hydroxydanaidal, a chiral dihydropyrrolizine derived from pyrrolizidine alkaloids in the larval diet.Creatonotos transiens was found to convert dietary heliotrine into (R)-(–)-hydroxydanaidal, with inversion at the single asymmetric carbon atom. The possible biological and biosynthetic significance of the chiral pheromone components are discussed, and they are compared with known examples of chiral lepidopteran pheromones.     

Sex Pheromone of the Cranberry Blossom Worm, Epiglaea apiata

The cranberry blossom worm, Epiglaea apiata (Grote) (Lepidoptera: Noctuidae), is a major pest of cranberries in New Jersey. The female sexpheromone of this moth was identified as a blend of (Z)-9-hexadecenyl acetate (Z9-16:Ac), (Z)-9-tetradecenyl acetate (Z9-14:Ac), and tetradecyl acetate (14:Ac) by gas chromatographic–electroantennographic detection and gas chromatography–mass spectrometry. The ratio of the components in extracts of the female pheromone gland was determined to be 65 : 2 : 33 of the Z9-16:Ac, Z9-14:Ac, and 14:Ac, respectively. The double bond positions of the pheromone components were confirmed by dimethyl disulfide derivatization. In addition to the above three components, a mixture of C₄–C₁₀ aliphatic acids was present in both gland extracts and effluvia collections, and the acids elicited significant EAD responses from male moth antennae. However, addition of the C₄–C₁₀ aliphatic acids to the pheromone blend did not significantly increase trap captures. Three-hundred- and 1000-g doses of a synthetic blend containing Z9-16:Ac, Z9-14:Ac, and 14:Ac (65 : 2 : 33), on a rubber septum were more attractive to males than lower doses.     

Structural correlation between cuticular hydrocarbons and female contact sex pheromone of German cockroachBlattella germanica (L.)

The structural relationships between the cuticular hydrocarbons and the contact sex pheromone of the female German cockroach,Blattella germanica, were investigated. Cuticular hexane extracts were separated into hydrocarbon and ketone fractions by TLC or silicic acid column chromatography. The ketone fraction (which contains the major contact sex pheromone component) was analyzed by GC-MS before and after reduction to ydrocarbon. In addition to 3,11-dimethyl-2-nonacosanone, 3,11-dimethyl-2-heptacosanone was also identified. Females have the 3,11- and 3,9-dimethyl C₂₇ and C₂₉ alkanes, but only the 3,11- isomer of the dimethylketones. Inddition to the hydrocarbon components previously reported, a number of new components were characterized. Although the ratios of cuticular hydrocarbons differ among nymphs, adult males, and adult females, they have qualitatively identical hydrocarbon profiles, suggesting that the production of the contact sex pheromone results from the sex-specific oxidation of 3,11-imethylalkanes to pheromone components by the female.     

(3Z,6Z,9Z)-Nonadecatriene and enantiomers of (3Z,9Z)-cis-6,7-Epoxy-nonadecadiene as sex attractants for two geometrid and one noctuid moth species

Sex attractants for the geometrid mothsEufidonia convergaria andCaripeta angustiorata, and the noctuid mothRivula propinqualis have been elucidated during field screening of a series of (3Z,6Z,9Z)-triene hydrocarbons (C_17–22), and the racemic and enantiomerically enriched monoepoxydienes derived from those hydrocarbons. Biologically active compounds were identified by a combination of field testing of synthetic standards, electroantennography, and coupled gas chromatography-electroantennogram detection.E. convergaria males were optimally attracted by a 11 blend of (3Z,9Z)-(6S,7R)-epoxy-nonadecadiene (3Z,9Z-6S,7R-epoxy-19H); other abbreviations follow the same system) with (3Z,6Z,9Z)-nonadecatriene (3Z,6Z,9Z-19H). The 6R,7S enantiomer of the epoxide had no apparent biological activity, either as an attractant or as a behavioral antagonist. Male moths also were attracted to blends of the C₁₈ and C₂₀ homologs of the triene and the epoxide. 3Z,6Z,9Z-19H and 3Z,6Z-cis-6,7-epoxy-19H were identified inE. convergaria female pheromone gland extracts. Males of the geometrid moth speciesC. angustiorata were attracted by a 11 blend of 3Z,6Z,9Z-19H and enantiomerically enriched 3Z,9Z-6R,7S-epoxy-19H. Males of the noctuid mothR. propinqualis were attracted by an approximately 101 blend of 3Z,6Z,9Z-19H and enantiomerically enriched 3Z,9Z-6S, 7R-epoxy-19H. The components were synergistic, with neither being attractive alone. The blend ratio was quite specific, as the attractiveness of blends decreased sharply on either side of the optimum ratio.Issued as NRC No. 30266.     

Hydrocarbons ofNasutitermes acajutlae and comparison of methodologies for sampling cuticular hydrocarbons of caribbean termites for taxonomic and ecological studies

Using data from the arboreal nestingNasutitermes acajutlae (Holmgren), we propose standard collection and extraction methodology for characterization of cuticular hydrocarbons of termites under field conditions in the tropics. Specifically, we evaluated: (1) the effect of the duration and the number of extractions; (2) the effect of drying termites before extraction; (3) the effect of sample size; (4) the effect of solvents (ethanol versus hexane) on cuticular hydrocarbon profiles. Olefins comprise ca. 70% of the cuticular hydrocarbons ofN. acajutlae. Hydrocarbons consist of two distinct groups: early-eluting components, primarilyn-alkanes and methyl-branched alkanes, and late-eluting compounds, which consist almost exclusively of unsaturated components with one to six double bonds. Soldiers have more early-eluting compounds than workers or alates. Nests from the same island had qualitatively similar, but quantitatively dissimilar hydrocarbon mixtures. Brief extractions of 300 live workers in 10 ml of hexane for only 20 sec produced a hydrocarbon mixture equivalent to a 10-min extraction. Long-term extraction of 300 workers in hexane for two years resulted in different mixtures of hydrocarbons. Drying workers tended to enhance extraction of the less abundant unsaturated compounds such as C_41.4 and C_41.5. A single extraction of a minimum of 100 workers (live or dried), with hexane for 20 sec to 10 min is best; these extraction regimes resulted in mixtures of hydrocarbons that are quantitatively very similar. For quantitative comparisons, extracts from dried samples should not be compared to those from live samples. Storage in ethanol caused numerous unidentified, nonhydrocarbon compounds to be extracted either from the cuticle or from internal tissues.     

Cuticular lipids of the booklouse,Liposcelis bostrychophila: hydrocarbons,aldehydes, fatty acids,and fatty acid amides

The booklouse, Liposcelis bostrychophila, is an increasingly common pest of stored food products worldwide. We report here the cuticular lipid composition of this pest (the first report of the hydrocarbons of any member of the Order Psocoptera and the first report of fatty acid amides as cuticular components for any insect). No unsaturated hydrocarbons were present. A homologous series of n-alkanes (C₂₁–C₃₄), monomethyl alkanes (3-, 4-, 5-, 7-, 9-, 11-, 12-, 13- and 15-methyl-) with a carbon chain range of C₂₈–C₄₂, and dimethyl alkanes (3, 7-; 9, 13-; 11, 15-; 13, 17-; 9, 21-; 11, 19-; and 13, 21-); with a carbon number range of C₃₁–C₄₃ were identified. The relative abundances of these hydrocarbons were low, comprising approximately 0.0125% of total biomass. The amides were a homologous series (C₁₆–C₂₂ in chain length), with the major amide being stearoyl amide. In addition to the amides, free fatty acids (C_16:1, C_16:0, C_18:2, C_18:1, and C_18:0 in chain length) and three straight chain aldehydes (C₁₅, C₁₆, and C_17:1 in chain length) also occurred as cuticular components. These findings are discussed in terms of the chemical and physiological ecology of this species.     

Mechanism underlying cuticular hydrocarbon homogeneity in the antCamponotus vagus (SCOP.) (Hymenoptera: Formicidae): Role of postpharyngeal glands

The aim of the present study was to investigate the regulation and the homogeneity of the chemical signature between members ofCamponotus vagus after experimentally changing the cuticular chemical signature by topically applying hydrocarbons. Topical application of pentane (solvent) to the cuticle of isolated workers led to a significant decrease in the quantities of the cuticular hydrocarbons measured within 3 hr, followed by an increase within the following 3 hr and a period of relative stability from 9 hr to 14 days. On the other hand, after topical application to isolated workers ofn-tetracosane, a hydrocarbon existing only in trace quantity in this species, the quantity of this hydrocarbon measured over time in the epicuticular wax tended to level out at about 14 days after treatment. In contrast, topically applied (Z)-9-tricosene, an unsaturated hydrocarbon not normally synthesized by this species, decreased dramatically within a few hours and had completely disappeared within 14 days. (Z)-9-Tricosene applied to one member of a group was present in the postpharyngeal glands of the other members from 30 min to seven days of cohabitation. The highest levels were recorded in all six workers in each group after one day. GC-MS analyses showed that (Z)-9-tricosene was present in the cuticles of some untreated workers only after four and seven days of cohabitation with a treated worker. These data suggest: (1) that the deposited (Z)-9-tricosene decreased very quickly on the cuticle of the treated worker, although the total amount was spread over the cuticle and postpharyngeal gland and (2) that it was absorbed by the nontreated workers via the postpharyngeal glands during licking or grooming activities and reincorporated into the cuticle at four and seven days. When the treated worker was separated from the other ants by a wire mesh, (Z)-9-tricosene was detected neither in the cuticle nor in the postpharyngeal gland of nontreated workers.     

Electrophysiological and chemical analysis of sex pheromone communication system of the mottled umber,Erannis defoliaria (Lepidoptera: Geometridae)

(Z,Z,Z)-3,6,9-nonadecatriene (Z3,Z6,Z9–19Hy) and (Z,Z)-3,9-cis-6,7-epoxy-nonadecadiene (Z3,Z9-cis-6,7-epo-19Hy) were identified in pheromone gland extracts from femaleErannis defoliaria. The two components were found in a 13 ratio, with the main component,Z3,Z9-cis-6,7-epo-19Hy present at an amount of about 1.5 ng per female. The components were identified by means of gas chromatography-mass spectrometry, gas chromatography-electroantennography and gas chromatography-single sensillum recordings. Single sensillum measurements on the male antenna showed two physiological types of sensilla. One type was characterized by a large spike amplitude cell responding toZ3,Z9-cis-6,7-epoxy-19Hy and a small spike amplitude cell responding toZ3,Z6,Z9–19Hy. A second type responded only with a large spike amplitude cell to the epoxide, and this cell was inhibited by the triene. Of the two pheromone components, the epoxide gave the higher response in the EAG tests. Preliminary field tests support the identification of the pheromone components. The epoxide was also found to be present in the extract of the pheromone gland ofColotois pennaria, and males ofC. pennaria andAgriopis marginaria were trapped by the mixture of the identified compounds.     

Cuticular hydrocarbons of the paper wasp,Polistes fuscatus: A search for recognition pheromones

The cuticular chemicals of 124 individual wasps (foundresses and workers) from 23 colonies ofPolistes fuscatus were analyzed. The compounds identified, all of which were hydrocarbons, were similar to those of other vespid wasps in that the bulk of the hydrocarbons were 23–33 carbons in chain length. However, the hydrocarbon profile ofP. fuscatus differed from those of its congeners in its proportions of straight-chain alkanes, methylalkanes, and alkenes. Three of the 20 identified hydrocarbons, 13- and 15-MeC₃₁, 11,15- and 13,17-diMeC₃₁, and 13-, 15-, and 17-MeC₃₃, had properties postulated for recognition pheromones: colony specificity, efficacy in assigning wasps to the appropriate colony, heritability, lack of differences between foundresses and workers, and distinctive stereochemistry.