Achyranthes is a genus of medicinal and ornamental plants in the amaranth family, Amaranthaceae. Chaff flower is a common name for plants in this genus. The Hawaiian species (A. divaricata, A. humile, and A. sandwicensis) are known in Hawaiian as kuluʻī.
A 2024 morphological and phylogenetic analysis by Vanessa Di Vincenzo et al. merged the genus Achyropsis and the Hawaiian genus Nototrichium into Achyranthes to make it monophyletic. The genus is characterized by solitary, fertile flowers.
↑Di Vincenzo, V., Berendsohn, W., Wondafrash, M. and Borsch, T. (2025), Phylogenetics and morphological character evolution in the achyranthoid clade (Amaranthaceae): Evidence to re-circumscribe the genera Achyranthes and Cyathula and to resurrect a third species of the former genus Sericocomopsis in East Africa. Taxon, 74: 66-100. https://doi.org/10.1002/tax.13284