The genus Mnesithea was erected by Carl Sigismund Kunth in 1829.

[9] This treatment was supported by Welker et al. in 2020, based on a molecular phylogenetic study,[10] and was used by the Germplasm Resources Information Network[11] and the Integrated Taxonomic Information System.

[1] In this circumscription, the genus has about 26 species including those formerly placed in Coelorachis.

[9] Alternatively, Plants of the World Online, following Veldkamp et al. in 2013,[12] treated Coelorachis as a synonym of Rottboellia,[13] with only seven species in the genus Mnesithea.

[8] Seven species were accepted in the narrow circumscription as of November 2024[update]:[8] Further species accepted when Coelorachis is synonymized with Mnesithea include the following, which other sources place in Rottboellia:[14][11][1]