Abstract
The adult female bolas spider Mastophora hutchinsoni feeds exclusively on attracted males of a few moth species. This exclusivity and the behavior of the approaching moths suggest that the spider aggressively mimics the sex pheromones of its prey species. Males of the bristly cutworm, Lacinipolia renigera, are a major prey of this spider, accounting for about two thirds of the biomass of prey consumed. Female bristly cutworms produce a pheromone blend consisting of (Z)-9-tetradecenyl acetate (Z9-14:Ac) and (Z,E)-9,12- tetradecenyl acetate (ZE-9,12-14:Ac). To determine if M. hutchinsoni females mimic the sex pheromone components and blend ratio of L. renigera, we collected volatiles from hunting adult female spiders and analyzed them with gas chromatography-electroantennographic detection (GC-EAD) and gas chromatography-mass spectrometry (GC-MS). GC-EAD analysis of volatile collections, using a male bristly cutworm antenna as the detector and two capillary columns of different polarities, revealed the presence of peaks with retention times (R(t)s) identical to Z9-14:Ac and ZE-9,12-14:Ac. The mass spectrum of a peak with R(t) of Z9-14:Ac was identical to the mass spectrum of the synthetic equivalent. There was an insufficient quantity of the compound with R(t) of ZE-9,12-14: Ac to get a full spectrum, but selective detection of ions at m/z 61 and 192 at the correct R(t) supported the identification. On average, the blend collected from spiders contained 54.8 ± 20.8 (SE) pg/min of Z9-14:Ac and 2.5 ± 1.7 (SE) pg/min of ZE-9,12- 14:Ac. The latter, on average, comprised 2.6 ± 0.7% of the total, which is similar to the blend ratio emitted by bristly cutworm females. Our results indicate that the adult female M. hutchinsoni produces an allomone blend that mimics not only the composition, but also the blend ratio, of the sex pheromone of a major prey species.
Original language | English |
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Pages (from-to) | 1235-1243 |
Number of pages | 9 |
Journal | Journal of Chemical Ecology |
Volume | 26 |
Issue number | 5 |
DOIs | |
State | Published - 2000 |
Bibliographical note
Funding Information:Acknowledgments—We thank B. Chastain, K. Johnson, and S. Mayes for their technical assistance. Drs. L. Rieske-Kinney and M. Sharkey reviewed an early draft of this manuscript. This material is based upon work supported by the National Science Foundation under grant IBN-97-22828. The GC-MSD system was purchased in part by funds from the University of Kentucky major equipment program (MRES94-01-Haynes). This investigation (paper no. 99-08-54) was conducted in connection with two projects of the Kentucky Agricultural Experiment Station.
Keywords
- Aggressive chemical mimicry
- Allomone
- Araneae
- Araneidae
- Insect pheromones
- Lepidoptera
- Noctuidae
- Pheromone emission
- Predation
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Biochemistry