| 1. |
- Unelius, C. Rikard, et al.
(författare)
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Volatiles from green-lipped mussel as a lead to vespid wasp attractants
- 2014
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Ingår i: Journal of applied entomology. - : Wiley. - 0931-2048 .- 1439-0418. ; 138:1-2, s. 87-95
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Tidskriftsartikel (refereegranskat)abstract
- Vespid wasps (Vespula vulgaris L. and V.germanica Fab. Hymenoptera; Vespidae) are highly abundant in 1 million ha of New Zealand's indigenous beech forests (Nothofagus spp.) and have had detrimental effects on the New Zealand native fauna. This hyperabundance is due in part to the vast supply of carbohydrate-rich honeydew produced by scale insects Ultracoelostoma spp. native to New Zealand. Current control methods include the use of wet cat food as a protein source with insecticide as a lure-and-kill-based system, but there are problems with fresh baits degrading rapidly, and a more durable formulation would enable the expansion and longevity of wasp control. Four crude protein baits were tested for vespid attraction. Green-lipped mussels had the highest vespid catch of the crude baits tested, and aged and fresh mussels were equally attractive. From headspace analysis of the green-lipped mussel volatiles, a series of butanoate esters, 3-octanone and 1-octen-3-ol were identified as possible attractants. These compounds were tested individually and in various blend combinations for the attraction of Vespula wasps in matagouri vegetation at the edge of beech forests. We found synergistic effects between single attractive compounds when tested in various combinations, and the multicomponent lures were more attractive to these wasps than heptyl and octyl butanoate, previously identified attractants for vespid species. The new multicomponent lures could form the basis for a new generation of attractants for social wasps that can provide sustained control methods for invasive vespid wasps.
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| 2. |
- El-Sayed, A. M., et al.
(författare)
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Geographic variation in pheromone chemistry, antennal electrophysiology, and pheromone-mediated trap catch of North American populations of the obliquebanded leafroller
- 2003
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Ingår i: Environmental Entomology. - 0046-225X .- 1938-2936. ; 32:3, s. 470-476
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Tidskriftsartikel (refereegranskat)abstract
- The total and relative amounts of (Z)-11-tetradecenyl acetate (Z11-14:Ac), (E)-11-tetradecenyl acetate (E11-14:Ac), (Z)-11-tetradecen-1-ol (Z11-14:OH) and (Z)-11-tetradecenal (Z11-14:Al), and the EAG response of male antennae to these pheromone gland compounds were compared in laboratory reared Choristoneura rosaceana Harris (Lepidoptera: Tortricidae) from British Columbia, Michigan, Ontario, New York, and Quebec. A field trapping experiment was conducted in each of these locations to determine the effect of Z11-14:Al on the numbers of moths captured. The amount of each of the four pheromone-gland compounds declined successively in moths from British Columbia, Quebec, Ontario, Michigan, and New York. The relative amount of Z11-14:Ac was greatest in moths from New York and smallest in moths from Ontario, whereas the relative amount of E11-14:Ac was greatest in moths from Ontario and smallest in moths from British Columbia. Moths from Ontario, Quebec, British Columbia, Michigan, and New York contained decreasing relative amounts of Z11-14:OH and Z11-14:Al. There was a trend of increasing antenna] sensitivity to each of the four pheromone-gland compounds in moths from New York, Michigan, Ontario, Quebec, and British Columbia. The addition of 1% Z11:Al to a three compound blend of Z11-14:Ac, E11-14:Ac and Z11-14:OH (97:2:1) resulted in a >twofold increase in average trap catch in British Columbia, Ontario, and Quebec; this compound had no effect on trap catch in Michigan or New York.
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| 3. |
- Manrique, G., et al.
(författare)
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Chemical Communication in Chagas Disease Vectors. Source, Identity and Potential Function of Volatiles Released by the Metasternal and Brindleys Glands of Triatoma infestans Adults
- 2006
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Ingår i: Journal of Chemical Ecology. - : Springer. - 0098-0331 .- 1573-1561. ; 32:9, s. 2035-2052
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Tidskriftsartikel (refereegranskat)abstract
- Compounds from the metasternal and Brindley's glands of the blood-sucking bug, Triatoma infestans, were identified by solid phase microextraction (SPME) and gas chromatography-mass spectrometry. Volatile compounds released by adult bugs during copulation or after mechanical disturbance were also characterized. Six compounds were identified and found consistently in all samples from metasternal glands. The most abundant were 3-pentanone, 2-methylbutanol, 3-pentanol, and an unidentified compound. The metasternal gland blends did not differ qualitatively between sexes. Compounds found in Brindley's glands were short chain acids, alcohols, esters, and a ketone with no qualitative differences between sexes. Isobutyric acid was the main component of this blend, and two new confirmed compounds were described as products of these glands: 2-butanone and 2-methylbutyric acid. 3-Pentanone was collected from the headspace over 33% of the copulating pairs of T. infestans. Volatiles found in the headspace of disturbed T. infestans adults included short-chain fatty acids, alcohols, esters, and ketones, with no qualitative differences between sexes. Both types of glands apparently discharge their contents after disturbance. However, most of the volatiles released by bugs after disturbance came from Brindley's glands. The locomotor activity of fourth instars increased significantly after stimulation with the odors emitted by disturbed adults, as compared with larvae stimulated by the odor of undisturbed adults or by clean air. We also studied the directional behavioral response of fifth instars to the disturbance scent in a locomotion compensator. Larvae exposed to volatiles released by disturbed adults walked away from the direction of the odor. The results suggest that this blend or part of it functions as an alarm pheromone for T. infestans. We suggest that the metasternal glands of this species are involved both in the sexual and the alarm contexts, and that the Brindley's glands probably have both alarm and defensive roles.
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| 4. |
- Baeckstroem, P., et al.
(författare)
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Convenient Method for the Synthesis of Lineatin, a Pheromone Component of Trypodendron-Lineatum
- 1991
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Ingår i: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 56:10, s. 3358-3362
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Tidskriftsartikel (refereegranskat)abstract
- Synthesis of racemic lineatin (1), a pheromone component of Trypodendron lineatum, is described. Condensation of 5-methyl-5-hexen-2-one (2) and triethyl phosphonoacetate with LiN(SiMe3)2 gave esters 3, which upon hydrolysis gave acids 4a-f. The bicyclo[3.2.0] ring compounds 5 and 6 were obtained via an intramolecular [2 + 2] addition by refluxing underivatized carboxylic acids 4a-f with NaOAc and Ac2O. Compound 5 was isomerized to the thermodynamically more stable isomer 6 using a Pd/C catalyst activated with hydrogen. Reduction of 6 with LiAlH4 gave the endo and exo isomers 7a and 7b (4:1). Isolation of the alcohol 7a followed by acetylation gave 8. Subsequent oxidation with OsO4 and methylmorpholine N-oxide gave diol 9. Cleavage of 9 with H5IO6 in diethyl ether gave keto aldehyde 10, which was converted to keto acetal 11. Treatment of 11 with MeMgBr followed by acidic workup gave 1. The overall efficiency is approximately 20%.
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| 5. |
- Borg Karlson, A. K., et al.
(författare)
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Floral fragrance chemistry in the early flowering shrub Daphne mezereum
- 1996
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Ingår i: Phytochemistry. - : Elsevier BV. - 0031-9422 .- 1873-3700. ; 41:6, s. 1477-1483
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Tidskriftsartikel (refereegranskat)abstract
- The floral fragrance of the shrub Daphne mezereum in central Sweden was collected by means of the head-space technique and investigated by GC-MS and multi-dimensional GC. (S)-(+)-Linalool was the main constituent (95%) of the flower fragrance and its enantiomeric purity exceeded 99% in the samples. The (2S, 5S)- and (2R, 5S)-furanoid and the (3R, 6S)- and (3S, 6S)-pyranoid linalool oxide isomers constituted 2-5% of the fragrance. The elution order of these compounds on a permethylated beta-cyclodextrin column is reported. A fragrance sample of D. mezereum as well as (S)-(+)-linalool attracted males of the vernal solitary bee species Colletes cunicalarius and Andrena cinerea. A racemic mixture of the two enantiomeric pairs of known furanoid linalool oxides was only weakly attractive to the bees. The role of the fragrance in the pollination specialization of the plant is discussed.
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| 6. |
- Brown, Robert L., et al.
(författare)
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Attraction of the invasive social wasp, Vespula vulgaris, by volatiles from fermented brown sugar
- 2014
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Ingår i: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703 .- 1570-7458. ; 151:2, s. 182-190
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Tidskriftsartikel (refereegranskat)abstract
- The introduction of invasive social wasp species of the genus Vespula (Hymenoptera: Vespidae) to New Zealand has caused a major ecological problem, particularly in the beech forests (Nothofagus spp.) of the South Island, where they have destabilized the native bird and invertebrate biodiversity. New attractants are under investigation as part of a search for pest management solutions. Fermenting brown sugar has been previously reported as a social wasp attractant. This work was undertaken to identify compounds from fermented brown sugar attractive to social wasps. Raw fermented brown sugar was confirmed to be attractive in a field trial and 10 chemical compounds present in the headspace were positively identified by coupled gas chromatography-mass spectrometry and synthetic references. During electroantennogram experiments, 3-methyl-1-butanol, 3-methylbutyl acetate, and ethyl hexanoate elicited high electrophysiological responses from Vespula vulgaris (L.) antennae. These compounds mediated attraction of V.vulgaris wasps in forest margins by trapping. A blend of these compounds could be used as a lure in a monitoring tool, or even a local suppression method if combined with a toxin.
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| 7. |
- Brown, Robert L., et al.
(författare)
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Invasive Vespula Wasps Utilize Kairomones to Exploit Honeydew Produced by Sooty Scale Insects, Ultracoelostoma.
- 2015
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Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 41:11, s. 1018-1027
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Tidskriftsartikel (refereegranskat)abstract
- Vespula wasps are widely distributed invasive alien species that are able to reach high population densities in the 1.2 M ha of beech forests (Fuscospora spp.) of New Zealand's South Island. These endemic temperate forests have an abundance of carbohydrate-rich honeydew produced by native scale insects (Ultracoelostoma spp.). A characteristic aroma is associated with the honeydew in beech forests, which we hypothesized is the signal used by wasps to harvest the vast resources previously exploited by birds and other insects. Volatile collections were taken of black beech tree trunks with honeydew and sooty mold present, and analyzed with a gas chromatograph-mass spectrometer. Eleven compounds (benzaldehyde, benzyl alcohol, 2-phenylethyl acetate, 2-phenylethanol, phenylacetaldehyde, methyl 2-phenylacetate, ethyl 2-phenylacetate, methyl salicylate, n-octanol, octan-3-ol, and 1-octen-3-ol) were positively identified from the headspace, and were shown to elicit an electrophysiological response from Vespula vulgaris worker antennae by using electroantennography (EAG). Field trials with delta traps individually baited with these compounds confirmed wasp attraction to 8 of the 11 compounds tested, with 2-phenylethyl acetate, methyl salicylate, and octan-3-ol capturing the same numbers of wasps as the control. In later trials, attraction to a 1:1 blend of benzaldehyde and n-octanol was significantly higher (45 %) than to any other treatment. Many of the chemicals identified are known to be associated with fermenting sugars, or with fungal aroma. Benzaldehyde and n-octanol are common compounds produced by many different species in nature. The ability to respond to generic signals emanating from sugar resources is likely to contribute to the success of V. vulgaris as an invasive species.
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| 8. |
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| 9. |
- Correa, A. G., et al.
(författare)
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Electrophysiological studies and identification of possible sex pheromone components of Brazilian populations of the sugarcane borer, Diatraea saccharalis
- 2002
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Ingår i: Zeitschrift für Naturforschung C - A Journal of Biosciences. - : Walter de Gruyter GmbH. - 0939-5075 .- 1865-7125. ; 57:7-8, s. 753-758
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Tidskriftsartikel (refereegranskat)abstract
- Virgin female gland extracts of sugarcane moth Diatraea saccharalis (Fabricius) (Lepidoptera: Pyralidae), from three locations in Brazil, have been analyzed. By GC-MS analysis and comparison of the chromatographic retention time of the components of the pheromone gland with those retention times of synthetic standards, we observed the presence of (Z)-hexadec-11-enal (1), hexadecanal (2), (9E,11E)-hexadecadienal (4), (9Z,11Z)-hexadecadienal (5) and (9E,11E)-hexadecadienal (6), as minor components besides the major constituent (9Z,11E)-hexadecadienal (3) already reported. We found no variations in the composition of the gland extracts deriving from the three Brazilian populations and only two compounds, (Z)-hexadec-11-enal (1) and (9Z,11E)-hexadecadienal (3), elicited antennal responses (GC-EAD). In electroantennography (EAG), however, pure compounds 1 and 3, a binary mixture containing 1 and 3, and a mixture containing all of the six synthetic compounds 1-6 elicited a depolarization in male antennae of D. saccharalis, without any statistically different delay. The EAG responses to the other isomers of 9,11-hexadecadienal were small and not significantly different from the control, except for the (9Z,11Z)-isomer (5) which showed an relatively strong electroantennal activity.
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| 10. |
- El-Sayed, Ashraf M., et al.
(författare)
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Climate change risk to pheromone application in pest management
- 2021
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Ingår i: The Science of Nature. - : Springer. - 0028-1042 .- 1432-1904. ; 108:6
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Tidskriftsartikel (refereegranskat)abstract
- Since of the first sex pheromone and the adoption of pheromone in pest management, the global pheromone market size has grown to reach USD 2.4 billion per year in 2019. This has enabled the development of environmentally friendly approaches that significantly reduce the application of pesticides. Recently, there have been reports of the failure of various commercial codlemone: (E,E)-8,10-dodecadien-1-ol formulations used for monitoring the apple pest codling moth, Cydia pomonella (L.). This work was initiated to investigate factors behind the lack of efficacy of codlemone lure in the Northern Hemisphere (Germany) and Southern Hemisphere (New Zealand). We hypothesised that the observed failure could be due to two main factors: (a) a shift in the response of male codling moth to codlemone and (b) degradation of codlemone under field conditions that renders the lure less attractive. Field trial tests of various doses and blends containing minor pheromone compounds suggested no change in response of male codling moth. The addition of an antioxidant and a UV stabiliser to codlemone resulted in a significant increase in the number of males caught in Germany, but not in New Zealand. Mean maximum temperatures during the growing season since 2004 indicate a 3 degrees C increase to 35 degrees C in Germany, but just a 1.5 degrees C rise to 30 degrees C in New Zealand. Chemical analysis of the lures used in the field trials in Germany and New Zealand indicated more degradation products and reduced half-life of the lures in Germany compared with those in New Zealand. Heating codlemone lures to 32 degrees C significantly reduced the number of males caught in traps and increased the isomeric and chemical impurities of codlemone compared with unheated lures. Our data provide the first evidence that climate change affects pheromone molecule stability, thus reducing its biological efficacy. Our finding suggests that climate change could be a general problem for chemical communication and, therefore, could affect the integrity of natural ecosystems.
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| 11. |
- El-Sayed, A M, et al.
(författare)
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Relative attractiveness of (10E)-dodecen-1-yl acetate and (4E,10E)-dodecadien-1-yl acetate to male spotted tentiform leafminers Phyllonorycter blancardella (F.)
- 2004
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Ingår i: Journal of Chemical Ecology. - 0098-0331 .- 1573-1561. ; 30:9, s. 1827-1838
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Tidskriftsartikel (refereegranskat)abstract
- The antennae of male spotted tentiform leafminers, Phyllonorycter blancardella, from Ontario, Canada, exhibited similar electroantennogram responses when stimulated with E10-12:Ac or E4,E10-12:Ac. In field trapping experiments, E10-12:Ac was two-fold or more attractive than E4, E10-12:Ac, and E4,E10-12:Ac did not enhance the attractiveness of E10-12:Ac. E4,E10-12:Ac has not been identified in the pheromone of P. blancardella and it is hypothesized that the structural similarity of this compound and E10-12:Ac, the major pheromone compound of this species, may be responsible for the electrophysiological and behavioral responses to E4,E10-12:Ac. The possible reasons for the disparity between the results of our field trapping experiments and those carried out in Nova Scotia, Canada, and Massachusetts, USA., where E4,E10-12:Ac was found to be two to four times more attractive to P. blancardella than E10-12:Ac, are discussed.
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| 12. |
- El-Sayed, A. M., et al.
(författare)
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Relative attractiveness of (10E)-dodecen-1-yl acetate and (4E,10E)-dodecadien-1-yl acetate to male spotted tentiform leafminers Phyllonorycter blancardella (F.)
- 2004
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Ingår i: Journal of Chemical Ecology. - : Springer. - 0098-0331 .- 1573-1561. ; 30:9, s. 1827-1838
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Tidskriftsartikel (refereegranskat)abstract
- The antennae of male spotted tentiform leafminers, Phyllonorycter blancardella, from Ontario, Canada, exhibited similar electroantennogram responses when stimulated with E10-12:Ac or E4,E10-12:Ac. In field trapping experiments, E10-12:Ac was two-fold or more attractive than E4, E10-12:Ac, and E4,E10-12:Ac did not enhance the attractiveness of E10-12:Ac. E4,E10-12:Ac has not been identified in the pheromone of P. blancardella and it is hypothesized that the structural similarity of this compound and E10-12:Ac, the major pheromone compound of this species, may be responsible for the electrophysiological and behavioral responses to E4,E10-12:Ac. The possible reasons for the disparity between the results of our field trapping experiments and those carried out in Nova Scotia, Canada, and Massachusetts, USA., where E4,E10-12:Ac was found to be two to four times more attractive to P. blancardella than E10-12:Ac, are discussed.
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| 13. |
- El-Sayed, A M, et al.
(författare)
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Sex pheromone of a North American population of the spotted tentiform leafminer, Phyllonorycter blancardella
- 2005
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Ingår i: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703 .- 1570-7458. ; 116:2, s. 143-148
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Tidskriftsartikel (refereegranskat)abstract
- The major sex pheromone compound of the spotted tentiform leafminer, Phyllonorycter blancardella (F.) (Lepidoptera: Gracillariidae), from Ontario, Canada, was identified as (10E)-dodecen-1-yl acetate (E10-12:Ac) using chemical analysis and field trapping experiments. The minor compounds (10E)-dodecen-1-ol (E10-12:OH) (4.6%), dodecan-1-ol (12:OH) (2.3%), and (10Z)-dodecen-1-yl acetate (Z10-12:Ac) 1.6% were also identified. The dienic acetate (4E,10E)-dodecadien-1-yl acetate (E4,E10-12:Ac), a compound reported to be attractive to P. blancardella, was not found in the glands of this population. A two-component blend of the major and one of each the three minor compounds, in ratios similar to those found in the sex pheromone gland, did not increase the attractiveness of traps baited with synthetic pheromone. The minor compounds E10-12:OH and 12:OH were not attractive to P. blancardella when tested individually. Z10-12:Ac was attractive to P. blancardella, although traps baited with this compound captured only 2% of the moths that were captured in traps baited with the main compound. A four-component blend of the major and each of the three minor compounds (100 : 1 : 1 : 1) was not more attractive than the major compound alone. The related species Phyllonorycter mespilella was captured in traps baited with E10-12:Ac.
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| 14. |
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| 15. |
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| 16. |
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| 17. |
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| 18. |
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| 19. |
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| 20. |
- Marshall, D. G., et al.
(författare)
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Morganella morganii bacteria produces phenol as the sex pheromone of the New Zealand grass grub from tyrosine in the colleterial gland
- 2016
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Ingår i: The Science of Nature. - : Springer Science and Business Media LLC. - 0028-1042 .- 1432-1904. ; 103:7-8
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Tidskriftsartikel (refereegranskat)abstract
- Costelytra zealandica (Coleoptera: Scarabeidae) is a univoltine endemic species that has colonised and become a major pest of introduced clover and ryegrass pastures that form about half of the land area of New Zealand. Female beetles were previously shown to use phenol as their sex pheromone produced by symbiotic bacteria in the accessory or colleterial gland. In this study, production of phenol was confirmed from the female beetles, while bacteria were isolated from the gland and tested for attractiveness towards grass grub males in traps in the field. The phenol-producing bacterial taxon was identified by partial sequencing of the 16SrRNA gene, as Morganella morganii. We then tested the hypothesis that the phenol sex pheromone is biosynthesized from the amino acid tyrosine by the bacteria. This was shown to be correct, by addition of isotopically labelled tyrosine (C-13) to the bacterial broth, followed by detection of the labelled phenol by SPME-GCMS. Elucidation of this pathway provides specific evidence how the phenol is produced as an insect sex pheromone by a mutualistic bacteria.
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| 21. |
- Unelius, C. Rikard, 1958-, et al.
(författare)
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Combining odours isolated from phylogenetically diverse sources yields a better lure for yellow jackets
- 2016
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Ingår i: Pest Management Science. - : Wiley. - 1526-498X .- 1526-4998. ; 72:4, s. 760-769
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Invasive wasps have major impacts on bird populations and other biodiversity in New Zealand beech forests, and new solutions are needed for their management. Baits were combined from four phylogenetically diverse sources (protein and carbohydrate) to improve attraction to a level that could be used as the basis for more powerful attract-and-kill systems. Many compounds from honey, scale insect honeydew, fermenting brown sugar and green-lipped mussels were highly attractive and, when combined, outcompeted known attractants.RESULTS: The equivolumetric lure (equal parts of 3-methylbut-1-yl acetate, 2-ethyl-1-butanol, 1-octen-3-ol, 3-octanone, methyl phenylacetate and heptyl butanoate), gave a 5-10-fold improvement over the known attractant, octyl butanoate, and other previously patented lures. An economically optimised lure of the same compounds, but in a ratio of 2:1.6:1:1:2:2.4, was equally attractive as the equal-ratio lure. Pilot mass trapping attempts with this latter lure revealed that >400 wasps trap(-1) day(-1) could be caught at the peak of the season.CONCLUSION: The new lures are comprised of compounds from animals, plants and fungi, thus targeting the omnivorous behaviour of these wasps. © 2015 Society of Chemical Industry.
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| 22. |
- Unelius, C. Rikard, et al.
(författare)
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Comparisons of traps and lures for monitoring grass grub Costelytra zealandica
- 2008
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Ingår i: New Zealand Plant Protection. - : New Zealand Plant Protection Society. - 1175-9003 .- 1179-352X. ; 61, s. 215-221
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Tidskriftsartikel (refereegranskat)abstract
- Phenol the attractant pheromone of adult males of the native New Zealand grass grub Costelytra zealandica (White) is produced in the beetles as the result of bacterial degradation of tyrosine A lure consisting of a resin impregnated with phenol has been widely used to monitor male beetle flight activity The present formulation is highly attractive for the first week in the field but then loses activity rapidly A number of phenolcontaining formulations were tested to improve the lure A new formulation gave lower catches that were more stable with time producing data more suitable for population density estimation Phenylacetaldehyde a bacterial metabolite of phenylalanine was tested as a possible synergist to phenol Field results showed that this floral compound exhibited no behaviourallyactive properties to grass grubs when tested together with phenol Catches with water traps were compared with those in sticky delta and flat delta traps in two vineyards and in pasture Water traps caught four times more beetles
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| 23. |
- Unelius, C. Rikard, et al.
(författare)
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Identification and electrophysiological studies of (4S,5S)-5-hydroxy-4-methyl-3-heptanone and 4-methyl-3,5-heptanedione in male lucerne weevils
- 2013
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Ingår i: The Science of Nature. - : Springer Science and Business Media LLC. - 0028-1042 .- 1432-1904. ; 100:2, s. 135-143
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Tidskriftsartikel (refereegranskat)abstract
- An investigation to identify a sex or aggregation pheromone of Sitona discoideus GyllenhAyenl (Coleoptera: Curculionidae) is presented. Antenna flicking and attraction behaviors evoked by conspecifics of both sexes were recorded in arena bioassays, where attraction of females to males was observed. Air entrainment of both males and females was conducted in separate chambers. Gas chromatographic-mass spectrometric analysis of headspace volatiles revealed that two male-specific compounds, 4-methyl-3,5-heptanedione (major) and (4S,5S)-5-hydroxy-4-methyl-3-heptanone (minor), were emitted during the autumnal post-aestivatory flight period. The stereoisomers of the minor component were separated by enantioselective gas chromatography and their absolute configurations assigned by NMR (diastereomers) and the known preference of enantioselective transesterification reactions catalyzed by Candida antarctica lipase B. Electroantennogram and single sensillum recording studies indicate that 4-methyl-3,5-heptanedione as well as all individual stereoisomers of 5-hydroxy-4-methyl-3-heptanone are detected by the antennae of male and female S. discoideus. Further, single sensillum recordings suggest that both sexes of S. discoideus have specialized olfactory receptor neurons (ORNs) for detecting 4-methyl-3,5-heptanedione and different populations of stereoselective ORNs for detecting the stereoisomers of 5-hydroxy-4-methyl-3-heptanone. Some of these stereoselective ORNs appear to be sex-specific in S. discoideus.
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