X-ray tomographic analysis of the initial structure of the royal chamber and the nest-founding behavior of the drywood termite Incisitermes minor

Abstract

The nesting biology of the drywood termite, Incisitermes minor, is poorly understood. To date, no published data are available regarding the in situ nest-gallery development of I. minor. Three naturally infested Sitka spruce (Picea sitchensis Bong. Carriere) timbers were analyzed by X-ray computer tomography to observe the structure of the first royal chamber and the termite’s nest-founding behavior. One timber was infested by a group of termites which emerged from their natal nest. The other two timbers were infested by dealate reproductives from the nuptial flight. The study revealed that the drywood termite engages in outside foraging activity and has great foraging flexibility. Computer tomographic images also revealed that I. minor reproductives showed anatomical selectivity in their nest-founding activity. The structure of the initial royal chambers varied to follow the anatomical texture of the timbers, which resembled either a European pear shape or a cashew nut shape.