Arrow shows location of dragonfly arrestor mechanism. Artist: Meghan Hanson Powers. Copyright: All rights reserved by Biomimicry 3.8 Institute.
Two kinds of top and bottom microtrichia, separated on the top and attached on the bottom. Artist: Meghan Hanson Powers. Copyright: All rights reserved by Biomimicry 3.8 Institute.
“The arrester or fixation system of the head in adult Odonata is unique among arthropods. This system involves the organs of two body segments: the head and the neck. It consists of a skeleton-muscle apparatus that sets the arrester parts in motion. The parts comprise formations covered with complicated microstructures–fields of microtrichia on the rear surface of the head and post-cervical sclerites of the neck. The arrester immobilizes the head during feeding or when the dragonfly is in tandem flight. Thus, it may serve as an adaptation to save the head from violent mechanical disturbance and to stabilize gaze in a variety of behavioural situations.” (Gorb 1999:525)
“The arrester system includes the adjusting organs of two body segments–the head and neck–and consists of (i) the skeleton-muscle apparatus that moves the head and neck sclerites, (ii) co-opted microsculptures, which are fields of microtrichia on the rear surface of the head (MFH) and on the post-cervical sclerites of the neck (SPCs), (iii) the secretory apparatus consisting of epidermal cells, which produces lipid substances which pass through porous channels in the cuticle into the region of contact between the MFH and SPCs, and (iv) sensory organs monitoring contact between the MFH and SPCs and the position of the SPCs relative to the other neck sclerites (Gorb 1991a)”. (Gorb 1999:525)