SEMIOCHEMICAL-MEDIATED LOCATION OF HOST HABITAT BY APANTELES CARPATUS(SAY) (HYMENOPTERA, BRACONIDAE), A PARASITOID OF CLOTHES MOTH LARVAE

In Y-tube olfactometer bioassays, adult Apanteles carpatus (Say), were attracted to beaver or rabbit pelts infested with larvae of the casem aking clothes moth (CCM), Tinea pellionella L. Porapak Q-captured vola tiles from a CCM-infested beaver pelt were also very attractive, where as isolated CCM larvae or larval feces were not. Coupled gas chromatog raphic-electroantennographic detection (GC-EAD) analysis of the Porapa k Q volatile extract revealed two compounds that elicited responses by A. carpatus antennae. Coupled CC-mass spectrometry (MS) in electron i mpact and chemical ionization modes of these compounds indicated, and GC-MS and GC-EAD of authentic standards confirmed, that they were nona nal and geranylacetone. While each compound singly did not attract A. carpatus, a 1:1 blend of both compounds was as attractive as the volat ile extract. Because these compounds are host habitat-derived, A. carp atus must be a habitat rather than host specialist, responding to kair omonal indicators of localized and specific habitats such as animal ha ir or feather. The tritrophic interaction between A. carpatus, its clo thes moth hosts and their animal-derived habitats is similar to the we ll-studied relationship between parasitoids of insect herbivores and t heir host plant habitats.