This study examines the feasibility of markingLygus hesperusKnight adults externally by submersion in rabbit immunoglobulin G(IgG) solution. Rabbit IgG retention time was measured in the laboratory on insects submerged in an IgG solution. We marked insects with rabbit IgG and ran an enzyme-linked immunosorbent assay (ELISA) with its complementary antibody (antirabbit IgG). We concurrently ran an ELISA assay using the same samples against an egg-specificL. hesperusmonoclonal antibody (MAb)to measure the presence ofL. hesperusegg antigen in the insect. A previously developed egg-specific MAb toL. hesperusenabled us to assay simultaneously adult females (which possess the egg antigen) and adult males for the presence ofL. hesperusegg antigen. This combination of techniques will enable us to examine the gut contents of potential predators ofL. hesperuseggs or adult females using whole body macerates while simultaneously evaluating the efficiency of lab-reared predators for augmentative biological control.