Volatile Constituents of the Bronze Orange Bug, <i>Rhoecocoris sulciventris</i>

Abstract

Preliminary experiments in April 1960 indicated that the bronze orange bug, Rhoecocoris suZciventris, secretes a stinking unsaturated aldehyde of pre-sumably defensive function, reminiscent of the occurrence of 2-hexenal in the cockroach Eurycotis jloriclana (Roth, Niegisch, and Stahl1956). A large number of the insects were collected in January 1961 to furnish adequate material for the identification of the steam-volatile constituents. While another examination (Waterhouse, Forss, and Hackman 1961) of these odorous constituents has recently been published, our work presented here provides a more complete list of the steam-volatile constituents. In Figure 1 are compared gas chromatograms of the oil obtained from the bugs by steam distillation and that ejected by the bugs under provocation. The steam distillate yielded in decreasing proportion, n-tridecane (78 % by wt.), trans-2-octenal (18 %), trans-2-octenyl acetate (2.1 %), n-dodecme (1-1 %), trans-2-decenal ( 0. 6 %), and four very minor constituents. The ejected secretion was similar but with the virtual absence of the octenyl acetate peak and the