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Defensive secretion of a carabid beetle,Helluomorphoides clairvillei
A B Attygalle1, J Meinwald, T Eisner
1Department of Chemistry, Cornell University, 14853, Ithaca, New York.
Journal of Chemical Ecology
|November 21, 2013
Summary
The rare Helluomorphoides clairvillei beetle
Area of Science:
- Entomology
- Chemical Ecology
Background:
- Carabid beetles are known for their defensive secretions.
- The chemical composition of these secretions can vary significantly between species.
Purpose of the Study:
- To analyze the chemical components of the defensive spray from a single female Helluomorphoides clairvillei.
- To assess the feasibility of characterizing secretory components from minimal samples.
Main Methods:
- Analysis of the defensive spray using gas chromatography-mass spectrometry (GC-MS).
- Quantification of ejected compounds relative to body weight.
Main Results:
- The defensive spray contained carboxylic acids (formic, acetic), aliphatic esters (nonyl acetate), and hydrocarbons (decane).
- A single female ejected approximately 1% of its body weight as formic acid (1.1 mg).
Conclusions:
- The defensive secretion of Helluomorphoides clairvillei is a complex mixture of volatile organic compounds.
- Chemical characterization of defensive secretions is possible even from very small sample sizes, facilitating research on rare species.
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