The stipe (the stalk of the leaf, below the blade) is slender, rounded, dull (rather than shiny), lacks hairs and scales, and varies from a bright to a dark chestnut-brown.

The pinnulets are broadly oblong to nearly orbicular (circular), obtuse (blunt) at the tip and truncate (abruptly cut off) to nearly cordate (heart-shaped) at the base, with entire margins.

Yellow farina is the most distinctive trait of A. flavens; it also differs in several more subtle characteristics, having a darker stipe and rhizome scales that are not crisped (wavy).

[5] Shortly thereafter, in 1806, Olof Swartz independently described the same species as Acrostichum albidulum, based on South American material from Luis Née.

However, delineating natural genera in the cheilanthoids has proven to be extremely difficult, and many different placements of the species were subsequently put forward.

In 1811, Nicaise Auguste Desvaux revived the genus Cincinalis with his own circumscription, distinguishing it by the presence of sporangia spreading more from the margins than in Pteris but not so widely as in Acrostichum.

[15] Rodolfo Amando Philippi described material from the Tarapacá Region of Chile as Cincinalis tarapacana in 1891,[16] but George Hieronymus, in 1909, considered it at most a form of P. nivea.

[17] Both Edwin Copeland and Charles Alfred Weatherby suggested in the 1940s that N. nivea and a group of related ferns might represent a genus distinct from Notholaena.

[20] The recognition of the N. nivea group as a genus was finally addressed in 1987 by Michael D. Windham, who was carrying out phylogenetic studies of the cheilanthoids.

[22] In 2018, Maarten J. M. Christenhusz transferred the species to Hemionitis as H. nivea, as part of a program to consolidate the cheilanthoid ferns into that genus.

tenera, elevating both to species level on the grounds of consistent differences in morphology and range and continued distinctness when growing sympatrically.