1987 Volume 22 Issue 2 Pages 222-228
A leaf feeding Coccinelidae, Epilachna vigintioctomaculata, is able to stay ant to walk on a vertically smooth surface such as a glass plate in the same manner as on a horizontal one. The insect is able to adhere to the underside of a glass plate and support a load of about five times of its body weight against the force of gravity. A large number of tenent hairs is distributed on the ventral side of the first and second tarsi of the fore-, mid-, and hind-legs in a pattern of a diagonal lattice. The tips of the hairs are bent and expanded in the form of a spatula. Footprints which consisted of a large number of minute droplets were observed on a glass plate on which an insect walked. The distribution of the droplets was of the same pattern as that of the tenent hairs. Thin layer chromatography substantiated the lipidal nature of the droplets. The tenent hairs and the lipids which were probably secreted from the hairs were considered to play important roles on the adhesion of the insect on vertically smooth surfaces against the force of gravity.