A species previously treated in Staurogyne (S. nitida) is elevated to the category of a new genus of Acanthaceae, subfamily Nelsonioideae, based on morphological and molecular data. The sole species, Aymoreana nitida, occurs in the Atlantic Forest of eastern Brazil, from southern Bahia to northern Espírito Santo. Aymoreana differs from other genera of Nelsonioideae by the combination of the calyx with subequal segments, the slightly zygomorphic corolla, the four didynamous stamens, and the asymmetric gynoecium. Morphological information is accompanied by a molecular phylogenetic tree, ecological data, a preliminary conservation assessment, and illustrations.