Exostema is a genus of flowering plants in the family Rubiaceae. It consists of trees and shrubs, endemic to the neotropics, with most of the species occurring in the West Indies.
Description Exostema is a genus of neotropical trees and shrubs. The flowers have a slender corolla tube with recurved corolla lobes. The stamens are inserted near the base of the corolla tube and exserted well beyond its mouth. The anthers are long and basifixed.
Systematics The type species for the genus is Exostema caribaeum. It is a tree of Central America and the Caribbean. Its lumber is of limited use.
Exostema was first named by Christiaan Hendrik Persoon as a subgenus of Cinchona.Christiaan Hendrik Persoon. 1805. Synopsis plantarum, seu Enchiridium botanicum, complectens enumerationem systematicam specierum hucusque cognitarum /curante. 1:196. It was first validly published as a genus by Aimé Bonpland in 1807.Alexander von Humboldt and Aimé Bonpland. 1807. Plantes équinoxiales recueillies au Mexique :dans l'île de Cuba, dans les provinces de Caracas, de Cumana et de Barcelone, aux Andes de la Nouvelle Grenade, de Quito et du Pérou, et sur les bords du rio-Negro de Orénoque et de la rivière des Amazones. 1:131. F. Schoell: Paris, France. The generic name is derived from the Ancient Greek words, exo, meaning "outside", and stema, "stamen".
As circumscribed in 2010, Exostema was probably polyphyletic. Species have since been moved to other genera.
Species , Plants of the World Online accepted the following species:
Exostema acuminatum Urb. Exostema caribaeum (Jacq.) Schult. Exostema coriaceum (Poir.) Schult. Exostema glaberrimum Borhidi & M.Fernández Exostema lancifolium Borhidi & Acuña Exostema nitens Urb. Exostema purpureum Griseb. Exostema salicifolium Griseb. Exostema spinosum (Le Vavass.) Krug & Urb.
References
External links Exostema At World Checklist of Selected Plant Families Exostema At Index Nominum Genericorum Exostema At Biodiversity Heritage Library Exostema At IPNI Exostema At GRIN taxonomy for plants Exostema At UniProt