Pygmy moths (Nepticulidae) associated with Asteraceae are poorly known and very rare worldwide. Recently, we discoveredmany leaf-mining nepticulids in South America feeding on Asteraceae. We review all known records of Asteraceae-feeding Nepticulidae, which in the Neotropics (including the Andes and Patagonia) previously included only Stigmella Schrank. We describe six new species of Stigmella from equatorial South America: S. jungiae Diškus and Stonis, n. sp. (feeding on Jungia L.f.), S. aeneola Diškus and Stonis, n. sp., S. violea Diškus and Stonis, n. sp., S. bracteata Diškus and Stonis, n. sp. (feeding on Liabum Adans.), S. spatiosa Diškus and Stonis, n. sp. (feeding on Ageratina Spach), and S. auripennata Diškus and Stonis, n. sp. (feeding on Baccharis L.). All new taxa are illustrated with photographs of the adults, their genitalia, and leaf mines. Additionally, leaf mines of three unknown nepticulid taxa on Jungia (aff. J. polita Griseb.), Piptocoma discolor (Kunth) Pruski, Gynoxys laurifolia (Kunth) Cass., and G. acostae Cuatrec. are documented for the first time. We diagnose and designate two new species groups and one new species complex in Stigmella.We discuss the origin and diversity of Asteraceae in the Neotropics and illustrate the distribution of Stigmella species feeding on representatives of Asteraceae at the tribal level.