Five species of Rejectaria Guene, including two newly described, were reared from Asplundia utilis (Oerst.) Harling, Asplundia microphylla (Oerst.) Harling, Carludovica costaricensis (Harling) L.O. Williams, and Cyclanthus bipartitus Poit. ex A. Rich., all Cyclanthaceae, in Area Conservacion de Guanacaste (ACG), Costa Rica: R. villavicencia Dognin, 1924, R. villosa Druce, 1891, R. magas Druce, 1891, R. richardashleyi sp. n. and R. ritaashleyae sp. n.. These represent the only Noctuoidea known to feed on Cyclanthaceae. Related species with unknown foodplant associations include R. atrax Dognin, 1891, R. splendida Schaus, 1912, and R. paratrax sp. n., the last of which is described from French Guiana, Venezuela, and Panama. The nomenclatural and phylogenetic challenges within the Herminiinae and the origins of cyclanth-feeding relative to fern- and palm-feeding are discussed.