Colouring matters of the Aphidoidea. XL. The external wax of the woolly apple aphid Eriosoma lanigerum (Hemiptera : Insecta)

Abstract

Apart from hydrocarbon and ester fractions the major components of the wax of the pemphigid Eriosoma lanigerum were found to be homologous diketo esters. On hydrolysis, keto alcohol and keto acid fractions were obtained. Their major constituents, 1-hydroxytetratriacontan-15-one and 13-oxodotriacontanoic acid have been synthesized. The wax of another pemphigid, Pemphigus spirothecae, was of similar composition, differing from that of the aphid Brevicoryne brassicae.