Endophytic feeding in insects is an adaptation to escape from environmental stress and from predators, and has originated independently in diverse insect families in four holometabolous orders: Coleoptera, Hymenoptera, Diptera and Lepidoptera. To be endophytic, insects needed to develop stout mandibles to burrow plant tissue, and afterward to avoid attack by hymenopteran parasitoids. Although recent leaf-miners have experienced adaptive radiation since the diversification of angiosperms in the Cretaceous, there remain basal lineages of leaf/stem-miners, which are associated with basal plants, such as liverworts, hornworts, lycopodiophytes, ferns, gymnosperms and basal angiosperms: e.g., Xyelidae, Sciaridae, Rhagionidae, Heterobathmiidae, etc. In contrast, recent colonization to basal plants has also occurred in agromyzids on leafy liverworts. Among these agromyzid species, transformation of leaf-mine into gall has occurred. The first-discovered bryophyte gall is a simple swelling, in clear contrast with elaborately ornamented or sclerotized galls on tracheophytes. Even microphylls of lycopodiophytes are mined by pallopterids. Floating and even submerged leaves of aquatic plants are mined by diverse insects including chironomids. Because leaf-miners are subject to severe attack by parasitoids, they have evolved various mining patterns to escape from the attack, e.g., branched mine, radiate mine, intermittent mine and midrib/petiole mine causing leaf fall.