We here propose a new, monotypic genus, Amiga Nakahara, Willmott & Espeland, gen. n., to harbor a common Neotropical butterfly, described as Papilio arnaca Fabricius, 1776, and hitherto placed in the genus Chloreuptychia Forster, 1964. Recent and ongoing molecular phylogenetic research has shown Chloreuptychia to be polyphyletic, with C. arnaca proving to be unrelated to remaining species and not readily placed in any other described genus. Amiga arnaca gen. n. et comb. n. as treated here is a widely distributed and very common species ranging from southern Mexico to southern Brazil. A neotype is designated for the names Papilio arnaca and its junior synonym, Papilio ebusa Cramer, 1780, resulting in the treatment of the latter name as a junior objective synonym of the former. A lectotype is designated for Euptychia sericeella Bates, 1865, which is treated as a subspecies, Amiga arnaca sericeella (Bates, 1865), comb. n. et stat. n., based on molecular and morphological evidence. We also describe two new taxa, Amiga arnaca adela Nakahara & Espeland, ssp. n. and Amiga arnaca indianacristoi Nakahara & Marín, ssp. n., new subspecies from the western Andes and eastern Central America, and northern Venezuela, respectively.