Chemical composition of footprints and cuticula lipids of three species of lady beetles

Abstract

Lady beetle can walk on a vertically smooth surface such as a glass plate in the same manner as on a horizontal one. It was reported that the insect probably released a non-volatile lipid secretion from the spatulate ends of the tenent hairs and this secretion was essential to the adhesion process on smooth surfaces against the force of gravity. We have studied footprint chemicals which were secreted from the tenent hairs of the three species of lady beetles Epilachna vigintiocotomaculta, Epilachna vigintioctopunctata and Coccinella septempuncata. The component of footprints was species specific and consisted of hydrocarbons and true waxes. The footprint chemicals were just identical with those of the cuticular waxes. The waxes of footprints were secreted larger amount from the tarsus than that from cuticular surface.