Ctenium is a genus of perennial grasses in the family Poaceae (order Poales), first described by the botanist Georg Wolfgang Franz Panzer in 1813 in Ideen zu einer Revision der Gräser. GBIF currently recognizes roughly 19 accepted species in the genus.
Wikipedia characterizes Ctenium simply as "a genus of African and American plants in the grass family," and GBIF's distribution records bear this out in more detail: documented native range spans tropical and southern Africa — Angola, Benin, Cameroon, the Central African Republic, Chad, Burundi, Ethiopia, Eswatini (Swaziland), the Cape Provinces of South Africa, and the Democratic Republic of the Congo — alongside populations in the Americas, including Brazil, Colombia, and Florida in the southeastern United States.
The genus has a history of shifting circumscription. Several older generic names — Aplocera, Campuloa, Campulosus, Monathera, Monocera, and Triatherus — are now treated by GBIF as synonyms of Ctenium, having been absorbed into it. Conversely, a number of species once classified in Ctenium (including C. digitatum, C. indicum, C. nukaviense, C. rupestre, and C. sechellense) have since been moved out to other genera such as Dactyloctenium, Enteropogon, and Tetrapogon.
Species recognized in the genus today include Ctenium aromaticum and Ctenium floridanum, both native to the southeastern United States, and Ctenium elegans, native to South America. Like other members of Poaceae, Ctenium grasses are wind-pollinated and are distinguished from relatives mainly by inflorescence and spikelet structure rather than showy flowers.
Distribution
Ctenium species occur across tropical and southern Africa (Angola, Benin, Cameroon, Central African Republic, Chad, Burundi, Ethiopia, Eswatini, Cape Provinces of South Africa, DR Congo) and in the Americas, including Brazil, Colombia, and Florida in the southeastern United States, per GBIF/WCVP distribution records — consistent with Wikipedia's broader description of the genus as African and American.
Taxonomy Notes
Ctenium Panz. was published in 1813 (Ideen Rev. Gräser: 38). GBIF treats the older generic names Aplocera, Campuloa, Campulosus, Monathera, Monocera, and Triatherus as synonyms of Ctenium. Several species once placed in Ctenium — C. digitatum, C. indicum, C. nukaviense, C. rupestre, and C. sechellense — have since been transferred to Dactyloctenium, Enteropogon, and Tetrapogon.
