Dear Editor,rnThe insect cuticle is a multifunctional coat that defines and stabilizes the shape of the body,appendages and internal organs,serves as a barrier against water and chemical compounds,such as insecticides,prevents infection and protects against predators (Moussian,2010).The surface of insects is covered by a lipid layer composed of diverse hy-drocarbons,wax esters,fatty acids,fatty alcohols,sterols and triglycerides.Delivery of lipids to the body surface occurs through the cuticle by a nano-canal system consisting of pore canals (PC) and wax canals (WC).Starting from the epi-dermis,PC run through the inner chitinous layer (procuticle)and ramify in the adjacent layer (epicuticle) as thinner WCs that terminate underneath the surface layer (envelope).The ultrastructure of PCs and WCs has been inferred from 2D sections observed by electron microscopy.Hence,to date,their overall spatial architecture is sketchy.Here,we used focused ion beam scanning electron microscopy (FIB-SEM)to describe directly the 3D architecture of PCs and WCs in the brown planthopper Nilaparvata lugens.N.lugens lives inpaddy fields and is active on the water surface and is therefore very well adapted to varying conditions of hu-midity.A complex network of genes is involved in producing the surface lipid barrier that enables the survival of N.lugens in its humid environment (Li et al.,2019b;Li et al.,2019a).Analyses of the structural basis of lipid barrier formation in this insect species,also in insects in general,are crucial for our understanding of how lipids are transported to the cuticle surface.