Erythroxylum is a genus of tropical flowering plants belonging to the family Erythroxylaceae, within the order Malpighiales. The genus comprises approximately 200–259 species (Kew's Plants of the World Online listed 259 species as of 2021), distributed primarily across tropical regions of South America, Africa, and Australia.
Plants in this genus are typically trees and shrubs. The genus is best known for two cultivated species, Erythroxylum coca and Erythroxylum novogranatense, both native to South America, which are the primary commercial sources of cocaine — a tropane alkaloid — and of coca tea, a mild stimulant consumed in Andean cultures. Many other species in the genus also contain cocaine and related tropane alkaloids in their leaves, though usually at lower concentrations.
Beyond its pharmacological significance, the genus has other ethnobotanical uses. Erythroxylum vaccinifolium, known as catuaba, is used as an aphrodisiac in Brazilian herbal drinks and traditional medicine. Erythroxylum australe was traditionally used by Aboriginal Australians in ceremonial rites.
Ecologically, Erythroxylum species serve as larval food plants for several Lepidoptera, including Morpho butterflies, Dalcera abrasa, and Agrias species.
Etymology
The name Erythroxylum derives from the Greek erythros (ἐρυθρός, "red") and xylon (ξύλον, "wood"), referring to the reddish wood characteristic of species in this genus. The genus was described by Patrick Browne in 1756.
Distribution
The genus is predominantly tropical, with its center of diversity in South America, particularly in Brazil and the Andean region. Species also occur in tropical Africa and Australia. The economically important coca species (E. coca, E. novogranatense) are native to western South America.
Ecology
Erythroxylum species function as larval host plants for several Lepidoptera. Morpho butterflies and Agrias species have been recorded feeding on Erythroxylum, as has Dalcera abrasa, which uses E. deciduum as a larval food source. The leaves of many species contain tropane alkaloids, which may also play a role in herbivore deterrence.
Cultural Uses
Erythroxylum coca and E. novogranatense have been cultivated for millennia in South America. Their leaves are chewed or brewed as coca tea as a mild stimulant and for altitude sickness relief. The leaves are also the industrial source of cocaine, used in medicine and illicitly. E. vaccinifolium (catuaba) is used in Brazilian traditional medicine as an aphrodisiac. E. australe was used by Aboriginal Australians in cultural and ceremonial practices.
