Mnesithea
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 as of 2024 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 as of 2024. 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 as of 2024:Mnesithea annua de Koning & Sosef - Western AustraliaMnesithea formosa de Koning & Sosef - Lesser Sunda Islands, New Guinea, Western Australia, Northern Territory, QueenslandMnesithea laevis Kunth - Fujian, Guangdong, Guangxi, Hainan, Taiwan, Japan incl Nansei-shotō, India, Indonesia, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; Pacific Islands Mnesithea mollicoma A.Camus - Guangdong, Guangxi, Thailand, Vietnam, Palawan, Java, Malaysia, Philippines, SulawesiMnesithea pilosa B.K.Simon - QueenslandMnesithea thailandica Traiperm & Boonkerd - ThailandMnesithea veldkampii Potdar, S.P.Gaikwad, Salunkhe & S.R.Yadav - MaharashtraFurther species accepted when Coelorachis is synonymized with Mnesithea include the following, which other sources place in Rottboellia:Mnesithea afraurita de Koning & Sosef Mnesithea aurita de Koning & Sosef Mnesithea balansae de Koning & Sosef Mnesithea cancellata Ridl. Mnesithea capensis de Koning & Sosef Mnesithea clarkei de Koning & Sosef Mnesithea cylindrica de Koning & Sosef Mnesithea geminata Ridl. Mnesithea glandulosa de Koning & Sosef Mnesithea helferi de Koning & Sosef Mnesithea impressa de Koning & Sosef Mnesithea khasiana de Koning & Sosef Mnesithea laevispica de Koning & Sosef Mnesithea lepidura de Koning & Sosef Mnesithea parodiana de Koning & Sosef Mnesithea ramosa de Koning & Sosef Mnesithea rottboellioides de Koning & Sosef Mnesithea rugosa de Koning & Sosef Mnesithea selloana de Koning & Sosef Mnesithea striata de Koning & Sosef Mnesithea tessellata de Koning & Sosef Mnesithea tuberculosa de Koning & Sosef