This paper describes the life history, host plant use, and myrmecophily of the Neotropical riodinid butterfly Adelotypa annulifera (Godman, 1903) in Tambopata, Peru. Eggs of A. annulifera are laid at the tips of new growth bamboo culm sheaths bearing extrafloral nectary sites where adult butterflies and ants gather to feed. Adelotypa annulifera larval stages are actively tended by multiple species of ants and were observed feeding on the extrafloral nectaries of the bamboo. Pupation of A. annulifera occurs on the host plant near the base of the bamboo. We also document the potential kleptoparasitic behavior of adult butterflies on ant species that tend the caterpillars. To our knowledge, this is the first account describing the immature stages and life history of a species belonging to the genus Adelotypa and the first account of adult riodinid butterfly kleptoparasitism on ants.