Kairomonal Responses of Coleoptera, Monochamus titillator (Cerambycidae), Thanasimus dubius (Cleridae), and Temnochila virescens (Trogositidae), to Behavioral Chemicals of Southern Pine Bark Beetles (Coleoptera: Scolytidae)

Abstract

The kairomonal responses of the sawyer beetle, Monochamus titillator (F.), and two predators, Thanasimus dubius (F.) and Temnochila virescens (F.), to southern pine bark beetle attractant and inhibitor mixtures were monitored in a series of replicated field bioassays. Tests were conducted in the presence and absence of measurable populations of the southern pine beetle, Dendroctonus frontalis Zimmermann. At three different test sites, M. titillator responded to traps baited with pheromone mixtures attractive to southern Ips spp. ( I. avulsus [Eichhoff], I. grandicollis [Eichhoff], I. calligraphus [Germar]), particularly those also containing D. frontalis inhibitor. This sawyer exhibited a reduced numerical response to a combination of D. frontalis attractant and D. frontalis inhibitor, but no significant response to traps baited solely with D. frontalis attractant. This is the first report of a sawyer beetle responding to pheromones of coinhabiting pine bark beetles. The predator T. dubius was captured in greatest numbers in traps baited with D. frontalis attractant, and in significantly lesser numbers in traps containing Ips attractant. In contrast to T. dubius , the predator T. virescens responded almost exclusively to Ips attractant and showed little response to D. frontalis attractant. These kairomonal responses explain previously observed temporal and spatial arrival patterns of these insect associates to bark-beetle-infested southern pines.