Mnesithea, or jointtail grass, is a genus of Asian, Australian, and Pacific Island plants in the grass family. The number of species placed in the genus varied considerably depending in large part on how the genus Coelorachis was treated. Sources that synonymized Coelorachis with Mnesithea accepted about 26 species. Those that synonymized Coelorachis with Rottboellia accepted about seven.

Taxonomy

The genus Mnesithea was erected by Carl Sigismund Kunth in 1829. The circumscription of the genus varied. A 2015 classification of Poaceae treated Coelorachis as a synonym of Mnesithea. This treatment was supported by Welker et al. in 2020, based on a molecular phylogenetic study, and was used by the Germplasm Resources Information Network and the Integrated Taxonomic Information System. In this circumscription, the genus has about 26 species including those formerly placed in Coelorachis. Alternatively, Plants of the World Online, following Veldkamp et al. in 2013, treated Coelorachis as a synonym of Rottboellia, with only seven species in the genus Mnesithea.

Species

Seven species were accepted in the narrow circumscription : Further species accepted when Coelorachis is synonymized with Mnesithea include the following, which other sources place in Rottboellia: