Release by Flight Exercise of a Chemotropic Response from Photopositive Domination in a Scolytid Beetle

Abstract

ONE of the remarkable features of barkbeetles and ambrosia beetles is their power of discovery and selection of host tree material. From a mass of varied material in a forest they select and bore into specific-parts of specific trees, usually only when those trees are under stress of age, environment, injury or encroaching death. Certain of the ambrosia beetles show a strong preference for logs that have ‘ripened’ for a period of some weeks or months after being-felled. The species, Trypodendron (Xyloterus) lineatum Oliver (Scolytidae), is one of these.