N. graciliflora is glabrous, typically highly bulbous in the lower portion of the pitcher, loses its wings in upper pitchers, has a less constricted petiole, and typically has more solid colorations or blushing appearances among other traits. N. alata is specifically an intermediate-highland species from northern Luzon with pubescent pitchers and often stems, wings on most uppers, a less bulbous base to the pitcher in most forms, typically either one solid color or notably spotted/mottled, and has narrow, constricted petioles and often a more obtuse apex to the leaf. It was always distinct from true alata, just lumped in with that species before the differences were bothered to be noted.